Coronavirus (COVID-19) Collection
Time from last immunity event against infection during Omicron-dominant period in Malaysia
The SARS-CoV-2 Omicron variant (B.1.1.529) and its prominent sublineages continue to be the dominant strains (>98%) circulating globally since February 2022 [1–3]. The spike mutations of Omicron resulted in higher viral transmissibility and capability to escape neutralizing antibodies from vaccinated sera [4]. Immune evasion is evident because a higher number of breakthrough and reinfection cases were observed during the Omicron-dominant period [5,6]. Symptomatic COVID-19 cases increased as studies found moderate booster effectiveness against Omicron infection, whereas the effectiveness against severe outcomes was largely preserved [7,8].Post-acute symptoms 3-15 months after COVID-19 among unvaccinated and vaccinated individuals with a breakthrough infection
Vaccination represents the most important strategy to prevent infection, severe complications, and death caused by SARS-CoV-2 (Feikin et al., 2022). SARS-CoV-2 vaccination may also reduce the risk of post-acute sequelae of SARS-CoV-2 infection (PASC) (Antonelli et al., 2022; Azzolini et al., 2022; Kuodi et al., 2022), but conflicting results have been presented (Taquet et al., 2022). We aimed to describe self-reported PASC symptoms, including memory and concentration problems, changes in smell and taste, fatigue, and dyspnea, persisting 3-15 months after a positive test in SARS-CoV-2 unvaccinated and vaccinated participants with a breakthrough infection.Clinical outcomes associated with Mu variant infection during the third epidemic peak of COVID-19 in Colombia
By July 2022, four COVID-19 epidemic peaks and 210 lineages have been registered in Colombia, including several variants of interest and concern (INS, 2022). However, a higher number of cases and deaths occurred during the third epidemic peak, when the B.1.621 (Mu) variant was associated with 50% of the cases in the country (Álvarez-Díaz et al., 2022a). Although several factors in the clinical history of patients with COVID-19 have been associated with a severe or fatal outcome, including comorbidities, age, and smoking history (Zhang et al.Effectiveness of messenger RNA vaccines against infection with SARS-CoV-2 during the periods of Delta and Omicron variant predominance in Japan: the Vaccine Effectiveness, Networking, and Universal Safety (VENUS) study
Vaccination against infection with SARS-CoV-2 in the general population of Japan began on April 12, 2021, and booster vaccination (the third dose) began on December 1, 2021. The Alpha (B.1.1.7) variant was gradually replaced by the Delta (B.1.617.2) variant beginning in June 2021, and the Delta variant accounted for approximately 80% of infections in Japan in August 2021 (National Institute of Infectious Diseases, 2021). The Delta variant predominated until the Omicron (B.1.1.529) variant surged in January 2022 (National Institute of Infectious Diseases, 2022; Ode et al.Critical pediatric neurological illness associated with COVID-19 (Omicron BA.2.3.7 variant) infection in Taiwan: immunological assessment and viral genome analysis in tertiary medical center
Since the COVID-19 pandemic outbreak, people all around the world have continued to fight it (Jian et al., 2022). However, as the virus evolves, more variants of concern have been reported (Chung et al., 2022). Patients with COVID-19 infection have also experienced neurological symptoms during the course of the infection (Nordvig et al., 2021). However, severe neurological complications have tended to be more common in children recently (Dilber et al., 2021; Valderas et al., 2022).Monitoring of SARS-CoV-2 circulation using saliva testing in school children in Rome, Italy
Since October 2020, the identification of suspected cases and contact tracing in the Lazio region have been supported by active surveillance initiatives in schools through antigen tests performed mainly on saliva (Bordi et al., 2021; Iwasaki et al., 2020). For the school year 2021-2022, the National Plan implemented the “Plan for monitoring of the circulation of SARS-CoV-2 in primary and lower secondary schools”. The Laboratory of Virology of the National Institute for Infectious Diseases “L. Spallanzani” was involved in the screening of saliva samples collected from students belonging to the local surveillance unit (ASL) RM3 of Rome.Validation of the NeuMoDx™ SARS-CoV-2 assay with COPAN eNAT® and E&O Viral PCR Sample Solution collection media types in comparison with other validated SARS-CoV-2 RNA assays
Reverse transcriptase polymerase chain reaction (RT-PCR) assays for the detection of SARS-CoV-2 RNA are the gold standard for diagnosis because of their high sensitivity and specificity (Park et al., 2020). Assay validation during the pandemic was challenging because of the need for rapid implementation of novel tests (Vandenberg et al., 2021).Admissions to a large tertiary care hospital and Omicron BA.1 and BA.2 SARS-CoV-2 polymerase chain reaction positivity: primary, contributing, or incidental COVID-19
Monitoring national hospitalization rates for COVID-19 has been essential throughout the pandemic to guide public health decision-making and to evaluate vaccine efficacy. However, with the rapid worldwide spread of the SARS-CoV-2 Omicron variant of concern (associated with a decreased severity) and increasing immunity against SARS-CoV-2, interpreting the true impact of these hospitalization rates has been complicated (Viana et al., 2022; World Health Organization, 2021).Assessing the proportion of the Danish population at risk of clinically significant drug-drug interactions with new oral antivirals for early treatment of COVID-19
Infection with SARS-CoV-2 usually causes mild to moderate respiratory disease. However, elderly patients and those with underlying chronic medical conditions are at high risk of progressing to severe COVID-19 (Ko et al., 2021; Thakur et al., 2021).Is a single dose of ChAdOx1 nCoV‐19 vaccine (AZD1222) enough for people with prior SARS‐CoV‐2 infection or baseline seropositive status?
At present, the most effective strategy against the COVID-19 pandemic is to reach a point where the majority of the population is immune, either from natural infection or vaccination. Complete vaccination is a herculean task in a populous country such as India due to limited vaccine availability. Two doses are needed for most vaccines, where the second dose acts as a booster. Alternatively, SARS-CoV-2 infection could act as a natural vaccine (Prime dose) after which, one dose could act as a booster dose and may give adequate immunity.A metropolitan-scale, three-dimensional agent-based model to assess the effectiveness of the COVID-19 Omicron wave interventions in a hyperdense city: a case study of Hong Kong
Despite its stringent containment measures, Hong Kong has experienced a most challenging COVID-19 wave due to the Omicron variant (Mallapaty, 2022). Implementing a citywide ‘compulsory universal testing’ (CUT) and a citywide lockdown was a subject of debate in March 2022 (South China Morning Post, 2022).Humoral and adaptive immune responses to the SARS-CoV-2 vaccine
Vaccines against SARS-CoV-2 prevent infection and adverse outcomes from SARS-CoV-2 (Olliaro et al., 2021). Elicitation of high affinity and durable protective antibody responses is a hallmark of a successful humoral immune response to vaccination (Turner et al., 2021). Antibody responses decline sharply at six months, particularly after SARS-CoV-2 mRNA vaccines (Collier et al., 2021). A recent study showed that after 20 weeks or more, the vaccination with two doses is effective against COVID-19–related hospitalization and death with a waning of the clinical protection in older adults and fragile/co-morbid patients (Andrews et al., 2022).SARS-CoV-2 intra-host evolution during prolonged infection in an immunocompromised patient
During the SARS-CoV-2 pandemic, several cases of prolonged infections were reported in immunosuppressed patients (Dolan et al., 2021). Most of these cases revealed an intra-host viral evolution, which allows the virus to accumulate mutations faster than during normal inter-host transmission (Avanzato et al., 2020; Leung et al., 2022). During these prolonged infections, SARS-CoV-2 can acquire mutations at key epitopes in the Spike (S) protein, potentially affecting virus replication, infectivity, and antigenicity, which are common to the variants of concern (VOCs) (European Centre for Disease Prevention and Control, 2022).Invasive Pneumococcal Disease diminish during the onset of COVID-19 in Japan between 2019 and 2022
Streptococcus pneumoniae can cause invasive pneumococcal disease (IPD) at a patient's sterile site, including the cerebrospinal fluid and blood, and commonly presents with septicemia, meningitis, and pneumonia (Dowell et al., 2003). In Japan, both children and older individuals receive public support for pneumococcal vaccination. Pneumococcal vaccine coverage has been increased since the launch of the vaccine program (Naito et al., 2020).Risk Factors Associated with Severe/Critical COVID-19 in People Living with HIV-1
Risk factors have been described as associated with severe forms of COVID-19 (Zhang et al., 2020). Persons living with HIV-1 (PLWH1) often carry such comorbidities. As shown by Bhaskaran et al (2021), PLWH1 are at a greater risk of developing a severe form of COVID-19. Our objective was to determine the characteristics associated with the development of a severe or critical form of COVID-19 in a cohort of PLWH1 who were followed up at the Bichat-Claude Bernard University Hospital in Paris, France.Real-world effectiveness of COVID-19 vaccination among children in Italy
In this study, we analyzed the clinical efficacy of mRNA-based COVID-19 vaccines among Italian children aged 5 to 11 years, using data published by the National Institute of Health. Vaccination status was associated with a reduced risk of COVID-19–related hospitalizations and intensive care unit (ICU) admissions, which were 41% (odds ratio, 0.59; 95% confidence interval [CI], 0.46-0.77) and 68% (odds ratio, 0.32; 95% CI, 0.04-2.63), respectively, lower in children who completed the vaccination cycle <120 days than in the unvaccinated matched population.High population burden of Omicron variant (B.1.1.529) is associated with the emergence of severe hepatitis of unknown etiology in children
The Omicron variant (B.1.1.529) emerged in late 2021, causing a widespread epidemic across the world, including in countries that had taken containment strategy with “zero-COVID” policy (Petersen et al., 2022). In industrialized countries that have experienced major extensive epidemics of Omicron, substantial fraction of the population was exposed, including children. For instance, a published seroepidemiological study in the United States indicated that approximately 75% of children have been infected by the end of February 2022 (Clarke et al., 2022).Early remdesivir to prevent severe COVID-19 in recipients of solid organ transplant: a real-life study from Northern Italy
COVID-19 remains a life-threatening disease for recipients of solid organ transplant (SOT) who might not mount an adequate protective response to vaccination (Sait et al., 2022). With this in mind, it is extremely relevant to deal with the recent SARS-CoV-2 infection in these patients, starting with treatments which may prevent the COVID-19 progression (National Institutes of Health, 2022b).Real-world effectiveness of BNT162b2 vaccine against SARS-CoV-2 infection among adolescents (12 to 17-year-olds) in Malaysia
Vaccinating against the SARS-CoV-2 virus to achieve high population immunity is essential to realise health and socio-economic goals driving the global COVID-19 vaccination strategy (World Health Organization. Strategy to achieve global COVID-19 vaccination by mid-2022.). In Malaysia, the national vaccination programme for COVID-19 began in February 2021 using a diverse platform of vaccines (Suah et al., 2021). It was demonstrated that they offer considerable protection, particularly against severe outcomes (Suah et al., 2022, 2021).Colorimetric detection of SARS-CoV-2 by uracil-DNA glycosylase (UDG) reverse transcription loop-mediated isothermal amplification (RT-LAMP)
It has been more than two years since the beginning of the SARS-CoV-2 pandemic. Rapid diagnostic methods such as reverse transcription loop-mediated isothermal amplification (RT-LAMP) (Notomi et al., 2000) are critically important to minimize the spread of the illness and protect the public.SARS-COV-2 IgG positivity in vaccinated and non-vaccinated Chilean children: a national cross-sectional study in schools
COVID-19 vaccination of children is gaining global support (Committee on Infectious Diseases, 2022), and data on immunogenicity and efficacy/effectiveness are increasing (Walter et al., 2022; Frenck et al., 2021; Han et al., 2021). Chile has rapidly advanced in a national vaccination campaign for children: as of February 17, 2022, 79% of children aged 3–17 years have been fully vaccinated (Ministerio de Salud Chile, 2022). Children aged 12–17 years have been vaccinated since June 22, 2021, with the mRNA Pfizer/BioNTech vaccine, followed weeks later by children aged 6–11 years, who received the inactivated Sinovac vaccine.COVID-19 vaccines provide better protection against related pneumonia than previous symptomatic infection
The burden of the COVID-19 pandemic in Mexico has been high and by mid-October 2021, more than 3.7 million laboratory-confirmed cases have been registered, with more than 280 thousand deaths.Using SARS-CoV-2 anti-S IgG levels as a marker of previous infection: example from an Israeli healthcare worker cohort.
Detecting current or previous SARS-CoV-2 infection is an essential component of pandemic management. Beyond case ascertainment and contact tracing, previous infection knowledge determines reinfection risk, the number and timing of vaccine doses required (Abu Jabal et al., 2021; Hansen et al., 2021), and can serve as evidence to attribute postviral symptoms to infection. Determining acute infection status relies on detecting viral DNA through polymerase chain reaction (PCR) or viral proteins through rapid antigen testing which has limited sensitivity (Wölfl-Duchek et al., 2022).Effect of a two-dose vs three-dose vaccine strategy in residential colleges using an empirical proximity network
When SARS-CoV-2 escalated to a pandemic in early 2020, universities and colleges were forced to pivot to virtual instruction. As of fall 2021, many institutions of higher education had reopened, adopting and often mandating mitigation measures like indoor masking, social distancing, regular testing, and vaccination. However, the emergence of the Omicron B.1.1.529 variant in November 2021 disrupted this new routine. The Omicron variant has been shown to be highly transmissible, with researchers estimating the effective reproduction number of Omicron as 3.19 times higher than that of the Delta strain (Ito et al., 2021).Diagnostic accuracy of SARS-CoV-2 saliva antigen testing in a real-life clinical setting
Testing for SARS-CoV-2 is an essential component of the pandemic response. Rapid antigen tests using saliva were suggested as a quick, simple, comfortable, and non-invasive testing method. Only minimal training is required to conduct these tests, facilitating application in various primary care and even self-testing settings. Several studies suggested that saliva antigen tests might have an adequate performance in diagnosing SARS-CoV-2 infection (Mattiuzzi et al., 2020). However, little is known about the diagnostic accuracy in real-life clinical settings, which might be significantly different from that reported in manufacturer data (Jegerlehner et al., 2021, Mattiuzzi et al., 2020).Third of patients have gustatory dysfunction 9 months after SARS-CoV-2 infection: the ANOSVID study
Olfactory and/or gustatory dysfunctions (OGD) are specific symptoms of COVID-19 (Salmon Ceron et al., 2020). Olfactory (OD) dysfunction have drawn considerable attention in the beginning of the pandemic, more than gustatory dysfunction (GD) (Klopfenstein et al., 2020; Parma et al., 2020). However, OGD's impact on quality of life seems to be majority due to GD (Coelho et al., 2021) which is defined as partial (hypogeusia) or complete (ageusia) loss of taste. Questions about COVID-19 GD remain, especially GD duration and the proportion of patients with persistent GD (Hopkins et al., 2021).Genomic profiles of vaccine breakthrough SARS-CoV-2 strains from Odisha, India
In India, five COVID-19 vaccines are authorized for emergency use, of which the adenovirus-vector based vaccine from Oxford University and AstraZeneca UK, marketed as COVISHIELD, and the indigenous inactivated virus vaccine COVAXIN by Bharat Biotech are majorly deployed through government and private healthcare centers. Both the vaccines pose tolerable safety outcomes and enhanced immune responses (Ella et al., 2021; Voysey et al., 2021). Recent in vitro studies showed that sera from the Pfizer- or the AstraZeneca-vaccinated individuals are less effective in neutralizing the Delta variant compared with the Alpha (B.1.1.7) variant (Planas et al., 2021).Decreased severity of the Omicron variant of concern: further evidence from Italy
We are currently facing a COVID-19 pandemic ongoing wave because of the Omicron variant, owing to its very high transmissibility with a doubling time between 1.5 to 3 days (Pascarella et al., 2021).COVID-19 vaccination and SARS-CoV-2 Omicron (B.1.1.529) variant: a light at the end of the tunnel?
We read with interest the recent article of Abdullah et al., who concluded that a significantly lower severity of illness associated with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron B.1.1.529 variant-driven epidemic wave had been observed in Tshwane, South Africa (Abdullah et al., 2021). This agrees with evidence recently published in other studies from South Africa, the United States, and the United Kingdom (Mahase, 2021), which also reported a similar suggestion of decreased pathogenicity associated with this new and highly mutated Omicron lineages (Lippi, Mattiuzzi and Henry, 2021).Revisiting SARS-CoV-2 environmental contamination by patients with COVID-19: The Omicron variant does not differ from previous strains
SARS-CoV-2 was shown to be transmitted mainly by respiratory droplets and direct contact with contagious individuals. Previously, we characterized this transmissibility through contaminated inanimate surfaces, which is indirect contact (Ben-Shmuel et al., 2020). Recently, emergence of the Omicron (B.1.1.529) variant caused a global surge in new cases, rapidly spreading while seemingly causing an altered, less severe disease (Araf et al., 2022; Kannan et al., 2021). The infection rate raised concerns regarding the variant's mode of spread in the populace.Number of initial symptoms is more related to long COVID-19 than acute severity of infection: a prospective cohort of hospitalized patients
Post–COVID-19 symptoms experienced by many survivors after infection have a further devastating effect. Reports of risk factors of long COVID-19 are rising, but data including reliable assessment of persistent symptoms through structured face-to-face follow-up visits are scarce (Halpin et al., 2021). Here we report a study assessing risk factors associated with post–COVID-19 symptoms in hospitalized patients, including those requiring intensive care unit (ICU) transfer 4 months after admission. We also provide data on objective measures of COVID-19 severity, for example, oxygen requirement, inflammatory biomarkers, and radiologic findings.Exported cases were infected on the way: A conjecture derived from analysis on Hong Kong monthly exported COVID-19 cases
During this COVID-19 pandemic, imported cases have played the role of triggering outbreaks in their arrival city and exported cases are used to infer the infection risk in their departure city (Imai et al., 2020; Menkir et al., 2021). Hong Kong, as a hub of international travel, faced this situation in particular. However, we argue that in the current phase of the pandemic, the role of exported cases in inferring the infection risk in their departure city loses its power; we use Hong Kong, an international travel hub, as an example.Comparison of the clinical sensitivity and specificity of two commercial RNA SARS-CoV-2 assays
In response to the COVID-19 pandemic, researchers have developed several diagnostic assays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Reverse transcriptase polymerase chain reaction (RT-PCR) is the gold standard for diagnosis of active SARS-CoV-2 infections because of its high sensitivity and specificity (Park et al., 2020). Automation in molecular diagnostics enables scaling of testing capacity, which is critical for enabling a large number of tests (Eigner et al., 2019).Antibody response after a third dose mRNA-1273 vaccine among vaccinated healthcare workers with two doses of inactivated SARS-CoV-2 vaccine
Health care workers (HCWs) are at the frontline battling against the COVID-19 pandemic and are categorized as a priority target group for COVID-19 vaccines. CoronaVac (Sinovac Life Sciences, China), an inactivated SARS-CoV-2 vaccine, was the initially available vaccine platform and primarily administered to Indonesian HCWs. Although previous clinical trial studies in China (Zhang et al., 2021) and Turkey (Tanriover et al., 2021) have evidenced the immunogenicity of 2-dose CoronaVac, the antibody levels predictive for SARS-CoV-2 protection has declined over time (Mok et al., 2021).Hospitalized patients with breakthrough COVID-19: Clinical features and poor outcome predictors
Vaccine breakthrough SARS-CoV-2 infection, that is, COVID-19 appearing in fully vaccinated patients, is an emerging challenge (Bahl et al., 2021). The severity of the disease in vaccinated patients has not often been described, and data are scarce regarding the groups most at risk and the prognosis and outcomes for patients who are hospitalized. (CDCMMWR, 2021; Tenforde et al., 2021).Independent risk factors of COVID-19 pneumonia in vaccinated Mexican adults
The availability of vaccines against coronavirus disease 2019 (COVID-19) represent a significant step toward ending the pandemic, and most COVID-19 vaccines confer close to 100% reduction in the risk of serious illness or death (Sharma et al. 2021). In Mexico, vaccination of the general population started in mid-February 2021, and by June 2021, 7 COVID-19 vaccines have received approval by health authorities for their application in Mexico: BNT162b2 (Pfizer, Inc./BioNTech), AZD1222 Covishield (AstraZeneca), Gam-COVID-Vac (National Center Gamaleya), CoronaVac (Sinovac Research and Development Co.), Ad5-nCoV Covidecia (CanSino Biologics Inc.), BBV152 Covaxin (Bharat Biotech International Limited), and Ad26.COV2-S (Janssen-Cilag).Exploring the trajectory recovery curve of the number of post-COVID Symptoms: The LONG-COVID-EXP-CM Multicenter Study
Evidence supports that between 35% to 60% of COVID-19 survivors will experience post-COVID-19 symptoms (Fernández-de-las-Peñas et al., 2021). The presence of post-COVID-19 symptoms is associated with worse quality of life (Malik et al., 2022). Almost 90% of studies investigating post-COVID-19 symptoms are cross-sectional (Fernández-de-las-Peñas et al., 2021; Malik et al., 2022). Longitudinal studies assessing symptoms at different follow-up up periods have provided heterogeneous results. Huang et al. (2021) reported a decrease of most post-COVID-19 symptoms, whereas Seeßle et al.COVID-19 and Lassa fever in Nigeria: A deadly alliance?
COVID-19 has become one of the most dangerous pandemics to cause severe problems for humanity in the past decades. SARS-CoV-2, a virus that causes COVID-19, emanated from China in December 2019, when public health officials alerted the World Health Organization (WHO) about pneumonia of an unknown etiology (WHO, 2021; Li et al., 2020). Subsequently, the disease rapidly spread worldwide. Nigeria faces a potential public health crisis owing to the synergistic epidemic of COVID-19 and other infectious diseases (Sherrard-Smith et al., 2020; Bouba et al., 2021).Severe Outcomes, Readmission, and Length of Stay Among COVID-19 Patients with Intellectual and Developmental Disabilities
Intellectual and developmental disabilities (IDDs) are a broad group of conditions characterized by physical impairments and impairments in learning, language, and/or behavior that begin during the developmental period. Comorbidities, immune dysfunction, or difficulty in accessing health care may put individuals with IDD at greater risk of severe COVID-19 outcomes (Kamalakannan et al., 2021). Population-based studies have predominately evaluated mortality risk but not other outcomes including length of stay (LOS) and readmission (Clift et al., 2021; Karpur et al., 2021; Perera et al., 2020; Turk et al., 2020).Symptoms Experienced at the Acute Phase of SARS-CoV-2 Infection as Risk Factor of Long-term Post-COVID Symptoms: The LONG-COVID-EXP-CM Multicenter Study
The presence of symptoms after COVID range from 35% to 60% (Fernández-de-las-Peñas et al., 2021). Identification of risk factors is needed for early monitoring of individuals at a high risk of developing symptoms after COVID, yet present data are still limited (Iqbal et al., 2021). Potential identified risk factors described in former literature include female gender, more onset symptoms (higher symptom load), older age, longer hospital stay, and a higher number of co-morbidities (Yong et al., 2021).Comparing self-reported reactogenicity between adolescents and adults following the use of BNT162b2 (Pfizer-BioNTech) messenger RNA COVID-19 vaccine: a prospective cohort study
The BNT162b2 messenger RNA COVID-19 vaccine, widely used in more than 100 countries worldwide, has been shown to be safe and effective in protecting populations from the infection of SARS-CoV-2 (Polack et al., 2020; Thomas et al., 2021; Walsh et al., 2020). According to clinical trial data, more than 80% of BNT162b2 recipients reported post-vaccination adverse reactions such as pain and tiredness, although an extremely small proportion of these reactions required medical interventions (Polack et al., 2020).Bloodstream infections in hospitalized patients before and during the COVID-19 surge in a community hospital in the South Bronx
New York City's (NYC) public health system, which predominantly serves lower-income communities, bore the burden of care and had to ramp up services to respond to the rapidly evolving COVID-19 pandemic. An increase in critical-care beds, staffing, and equipment was integral to the response, especially in our hospital in the South Bronx, where the number of intensive care unit (ICU) beds were augmented from 34 to 195 (Uppal et al., 2020). Hospitalized patients with COVID-19 usually have severe/critical infection with acute respiratory distress syndrome (ARDS), shock, coagulopathies, and multiorgan failure (Zaim et al., 2020).Role of institutional, cultural and economic factors in the effectiveness of lockdown measures
Nothing is possible without men, but nothing lasts without institutions.The impact of the COVID-19 preventive measures on influenza transmission: molecular and epidemiological evidence
We quantify the impact of COVID-19-related control measures on the spread of human influenza virus H1N1 and H3N2.Utilisation of SARS-CoV-2 rapid antigen assays in screening asymptomatic hospital visitors: mitigating the risk in low-incidence settings
During the COVID-19 pandemic, while mandatory point-of-entry screening of hospital visitors for respiratory symptoms/fever has been widely implemented (Wee et al., 2021a), asymptomatic visitors may escape detection and have been implicated in nosocomial clusters (Passarelli et al., 2021). However, screening for COVID-19 among hospital visitors poses significant challenges. Polymerase chain reaction (PCR) is unsuitable for testing visitors, with long turnarounds preventing real-time processing of results (Passarelli et al., 2021).SARS-CoV-2 variants with T135I nucleocapsid mutations may affect antigen test performance
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), similar to other RNA viruses, continually mutates, and new variants appear and eventually become dominant. Several SARS-CoV-2 genes have a tendency to evolve, including those encoding the nucleocapsid (N) and spike (S) proteins (Dilucca et al., 2020) [Au?1]. By the end of December 2020, new SARS-CoV-2 variants with multiple accumulated mutations had emerged, and these variants of concern (VOCs) have reportedly been associated with increased transmissibility or decreased effectiveness of available diagnostic tools (Boehm et al., 2021) [Au?1].Negative effect of the second dose of the BNT162b2 vaccine in a significant percentage of individuals with previous COVID infection
Despite the efforts made since the beginning of the pandemic, the infection caused by SARS-CoV-2 is far from being under control. In the current situation, vaccines can be a turning point in the fight against the virus, and all countries attempt to encourage vaccination in their inhabitants, mainly in those groups with the highest risk.Emergence of B.1.1.318 SARS-CoV-2 viral lineage and high incidence of alpha B.1.1.7 variant of concern in the Republic of Gabon
SARS-CoV-2 variants of concern (VOC) appear to spread more easily. Other emerging variants are also gaining attention, either known as a "variants of interest" (VOI) or "variants under investigation" (VUI), which increase transmission, warranting further studies. Since the onset of the COVID-19 pandemic, the SARS-CoV-2 genomes have accumulated genetic diversity, leading to increased transmission with altered viral properties (Kraemer et al. 2021).Mutations in emerging variant of concern lineages disrupt genomic sequencing of SARS-CoV-2 clinical specimens
Genomic sequencing of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has played a crucial role in managing the ongoing coronavirus disease 2019 (COVID-19) pandemic. This is especially true for variant of concern (VOC) lineages that have emerged globally since December 2020 (Chand et al., 2020; Cherian et al., 2021; Faria et al., 2021; Tegally et al., 2021a, 2021b; Rambault et al., 2020). Genomic sequencing has been instrumental in detecting and characterizing these lineages, tracking their global spread, and identifying local cases to control transmission.Emerging socio-economic disparities in COVID-19-related deaths during the second pandemic wave in Germany
During the first pandemic wave of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) from early March to mid-May 2020, the regional socio-economic patterning of infections in Germany differed from that reported from other high-income countries, revealing lower infection rates in socio-economically deprived areas of Germany in the early phase of the first wave (Wachtler et al., 2020a,b). However, during the second pandemic wave from late September 2020 to early March 2021, this pattern reversed, so that Germany's more deprived areas ended up with higher infection rates as of the end of 2020 (Hoebel et al., 2021).Performance and cost-effectiveness of a pooled testing strategy for SARS-CoV-2 using real-time polymerase chain reaction in Uganda
Coronavirus disease 2019 (COVID-19) continues to be an important global health problem with a significant impact on individual and global public health (Fauci et al., 2020). In the face of a rapidly spreading disease with a shortage of vaccines and/or effective treatment, rapid mass testing has been suggested as one of the measures to map, contain and mitigate the COVID-19 pandemic (Denny et al., 2020).Transient increase in plasma HIV RNA after COVID-19 vaccination with mRNA-1272
The latent viral reservoir is the main obstacle preventing HIV eradication, as the virus persists, integrated in long-lived quiescent cells. Immune stimulatory by their nature, vaccines have been evaluated as possible agents for ‘shock and kill’ strategies, which rely on using latency-reversing agents to activate HIV transcription and virion production in order to purge the reservoir.COVID-19 Pandemic Causes Increased Clinic Visits with Diagnosis of Tegumentary Leishmaniasis in Brazil in 2020
SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), a highly pathogenic β-coronavirus (family Coronaviridae) is the etiologic agent of COVID-19 (Coronavirus Disease 2019), the disease that gave rise to a difficult to control pandemic, especially in Brazil (Candido et al., 2020). Due to the lack of vaccines and drugs to contain the disease and given the high transmissibility of the virus through aerosols and droplets, it became consensual in several countries around the world to take respiratory etiquette measures to reduce interactions between people and reduce the risks of transmission and slow the progression of the pandemic (Szylovec et al., 2020).Rapid screening for SARS-CoV-2 VOC-Alpha (202012/01, B.1.1.7) using the Allplex™ SARS-CoV-2/FluA/FluB/RSV Assay
The current SARS-CoV-2 pandemic has crucially affected populations and healthcare systems worldwide. One of the challenges posed by SARS-CoV-2, similar to other RNA viruses, is represented by genomic variability, which may lead to the emergence of variants with improved transmissibility, increased virulence and/or immune-escape ability. Variants for which clear evidence is available about such modified features, which are likely to have an epidemiological impact, have been categorized as variants of concern (VOCs) (ECDC, 2020).Antibody response to the inactivated SARS-CoV-2 vaccine among healthcare workers, Indonesia
Healthcare workers (HCWs) are at risk for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection due to increased occupational exposure to SARS-CoV-2 (Nguyen et al., 2020). As well as being beneficial for the HCWs themselves, protecting HCWs from SARS-CoV-2 infection is important to prevent disease transmission in healthcare and community settings (Anonymous, 2020). In addition, protecting HCWs from coronavirus disease 2019 (COVID-19) is crucial for the preservation and protection of national healthcare systems (Anonymous, 2020).COVID-19 as the leading cause of hospital deaths in the Brazilian public health system in 2020
As a consequence of the high death toll of coronavirus disease 2019 (COVID-19), some countries, such as the USA, have already reported COVID-19 as one of the leading causes of death in 2020 (Ahmad and Anderson, 2021). Since the beginning of the COVID-19 pandemic, Brazil has experienced a rapidly increasing number of cases and deaths (Castro et al., 2021b). In addition, COVID-19 has spread asymmetrically and unequally across social and economic groups, as well as geographic regions, in Brazil, with the most vulnerable populations and the Northeastern and Northern regions being the most affected (Dall'Alba and Rocha, 2021; Rocha et al., 2021).Clinical Characteristics of Patients with Coronavirus Disease (COVID-19): Preliminary Baseline Report of Japan COVID-19 Task Force, a Nationwide Consortium to Investigate Host Genetics of COVID-19
The coronavirus disease (COVID-19) pandemic has had a devastating effect worldwide, including in Japan (see https://www.mhlw.go.jp/stf/covid-19/kokunainohasseijoukyou.html )(Ministry of Health, Labour and Welfare 2021). Host genome differences between populations may influence disease severity. This may explain why Asians, including Japanese, may have a lower risk of death (Price-Haywood, 2020; Zeberg and Pääbo, 2020). The Japan COVID-19 Task Force was established in early 2020 as a nationwide multicenter consortium.SARS-CoV-2 variants of concern are associated with lower RT-PCR amplification cycles between January and March 2021 in France
At least three SARS-CoV-2 variants are currently major sources of concern: Alpha from lineage B.1.1.7 [2,10], Beta from lineage B.1.351 [9], and Gamma from lineage P.1 [3]. Alpha and Gamma variants have been shown to be more contagious [2,3,10], while Beta and Gamma seem to evade immune responses [3,9]. Although the mechanistic bases are still being investigated, the increased transmissibility could be driven by the N501Y mutation and the Δ 69-70 deletion in the Spike protein [2], where also lies the E484K mutation related to immune escape [3,9].COVID-19 vaccination: effective utilization of low dead space (LDS) syringes
In the spring 2021, the only available vaccine for COVID-19 was the Pfizer-BioNTech mRNA COVID-19 vaccine (Polack et al., 2020), which was in limited supply in Japan. Also, it was difficult to procure specialized low dead space (LDS) syringes that can extract the full six doses from each vial of the Pfizer vaccine. When the Government provided the Pfizer vaccine to health care workers in our hospital, 1,242 candidates applied for their first shot. However, the use of regular syringes with high dead space meant that only five of the six doses could be extracted from each vial.Comparison of Allplex™ SARS-CoV-2 Assay, Easy SARS-CoV-2 WE and Lumipulse quantitative SARS-CoV-2 antigen test performance using automated systems for the diagnosis of COVID-19
As COVID-19 continues to strain public health systems and vaccination programmes race against new variants that might be more transmissible or capable of evading immune responses, the urgent need for simple, accessible, and frequent testing remains [Tan SH et al 2021]. Despite the fact that molecular assays are considered the gold standard for SARS-CoV-2 diagnosis, antigen detection assays currently deserve great attention, since they are intrinsically less laborious, require a shorter time to receive results and have the potential to satisfy the pressing demand for early SARS-CoV-2 infection diagnosis, thus allowing timely adoption of prevention measures against infection spread [Porte L et al 2020; Lambert-Niclot S et al 2020; Kobayashi R et al 2021].Clinical investigation of intestinal fatty acid-binding protein (I-FABP) as a biomarker of SARS-CoV-2 infection
SARS-CoV-2 exhibits tropism for the gastrointestinal tract; however, lesions in enterocytes and their correlation with disease severity and patient prognosis are still unknown.Real-Time SARS-CoV-2 Genotyping by High-Throughput Multiplex PCR Reveals the Epidemiology of the Variants of Concern in Qatar
Complementing whole genome sequencing strategies with high-throughput multiplex RT-qPCR genotyping allows for more comprehensive and real-time tracking of SARS-CoV-2 variants of concern. During the second and third waves of COVID-19 in Qatar, PCR genotyping, combined with Sanger sequencing of un-typeable samples, was employed to describe the epidemiology of the Alpha, Beta and Delta variants. A total of 9792 nasopharyngeal PCR-positive samples collected between April-June 2021 were successfully genotyped, revealing the importation and transmission dynamics of these three variants in Qatar.Neutralizing antibody response to SARS-CoV-2 persists 9 months post symptom onset in mild and asymptomatic patients
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the causative agent of coronavirus disease 19 (COVID-19), emerged in late 2019 and rapidly spread worldwide, causing a global pandemic (Lipsitch et al., 2020). Despite many insights on the virus, data regarding the long-term immune response are quite scarce (Huang et al., 2020), although this issue is of high clinical relevance.Reactions and COVID-19 disease progression following SARS-CoV-2 monoclonal antibody infusion
As the COVID-19 pandemic progressed and the capacity to care for severely ill patients stabilized, there was an increased interest in the development of treatments for mild to moderate COVID-19. Among these are SARS-CoV-2 monoclonal antibodies (mAbs). These lab-manufactured antibodies are engineered to bind to and neutralize SARS-CoV-2 under the assumption that this could reduce viral load or activity and thus reduce the severity of disease and the consequences, such as hospitalization.(Chen et al., 2021, Weinreich et al., 2021)Facial nerve palsy following the administration of COVID-19 mRNA vaccines: analysis of a self-reporting database
Newly developed coronavirus disease 2019 (COVID-19) mRNA vaccines (i.e. BNT162b2 (US Food and Drug Administration 2021) and mRNA-1273 (US Food and Drug Administration 2021)) have shown marked effects in preventing SARS-CoV-2 infection (Polack et al., 2020, Baden et al., 2021). While they frequently cause non-serious adverse events (AEs), such as fatigue, headache, chills, fever, and pain, serious AEs, such as anaphylaxis, have been rarely reported (US Food and Drug Administration 2021, US Food and Drug Administration 2021).The strength of association between pre-and post-booster BNT162b2 anti-SARS-CoV-2 antibodies levels depends on the immunoassay
Reliable evidence suggests that anticipating a humoral response to coronavirus disease 2019 (COVID-19) vaccines is essential for predicting their clinical effectiveness. Bergwerk et al. conducted a study in the largest medical center in Israel, where healthcare workers who received the Pfizer mRNA COVID-19 BNT162b2 vaccine were followed up with molecular or antigen testing, serologic assays, and genomic sequencing (Bergwerk et al., 2021). Notably, the levels of anti-SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) neutralizing antibody and anti-SARS-CoV-2 IgG were found to be nearly 64% and 49% lower in infected subjects than in matched uninfected controls.Risk factors associated with the mucormycosis epidemic during the COVID-19 pandemic
This study was performed to assess the risk factors driving the epidemic of coronavirus disease 2019 (COVID-19)-associated mucormycosis (COVID–Mucor) in India that has accompanied the COVID-19 pandemic, particularly during the second wave. Risk factors were analysed among 164 participants: 132 COVID–Mucor (cases) and 32 non-COVID–Mucor (controls). Data from a prospective cohort study of mucormycosis over a period of 1 year were used. Diabetes mellitus remained a significant risk factor in both groups (97%), while uncontrolled diabetes mellitus (odds ratio (OR) 4.6; P = 0.026) and newly detected diabetes (OR 3.3; P = 0.018) were more common among the cases.How to (ab)use a COVID-19 antigen rapid test with soft drinks?
With reasonably good specificity and sensitivity, the speed and convenience of COVID-19 antigen tests have led to self-testing in schools, offices, and universities in the European Union (EU). Although self-testing can be beneficial and increase the accessibility to testing, there are potential ways to confound a positive COVID-19 lateral flow test. We observed that all soft drinks, energy drinks, alcoholic beverages (vodka, whiskey, and brandy), commercially bottled mineral water, and carbonated mineral water caused the appearance of a red test line.Ultrastructural evidence for vertical transmission of SARS-CoV-2
Since the initial correspondence by Goldsmith et al. (2020) in The Lancet, numerous electron micrographs of putative severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virions in biopsy and autopsy tissues have been published. A recent review of these images (Bullock et al., 2021) indicated that previous ultrastructural reports of virions in placental tissue were misidentifications. Placental histology of mothers and neonates, both testing positive for SARS-CoV-2, is typified by chronic histiocytic intervillositis and trophoblast necrosis, with RNA in-situ hybridization/immunohistochemical findings localizing viral RNA/viral antigens to the syncytiotrophoblast (Schwartz and Morotti, 2020).Cycle threshold values are inversely associated with poorer outcomes in hospitalized patients with COVID-19: a prospective, observational cohort study conducted at a UK tertiary hospital
Clinicians need to identify patients with coronavirus disease 2019 (COVID-19) with a higher risk of poor outcome and mortality at an early stage of hospital admission. This prospective, observational cohort study was conducted at a UK tertiary care hospital to determine the relationship between the likelihood of death and cycle threshold (Ct) values in an unvaccinated UK population with COVID-19 on admission to hospital. Statistical adjustment was made for other known risk factors associated with poor outcome.Severe features during outbreak but low mortality observed immediately before and after a March–May 2020 COVID-19 outbreak in Stockholm, Sweden
Excess all-cause mortality is increasingly being used to monitor the timing and severity of COVID outbreaks; however the COVID-attributable fraction of the all-cause mortality is not always clear ( www.euromomo.eu ). When calculating weekly excess mortality, fluctuations in mortality rates by calendar year are minimized by calculating a baseline mortality over several years (Ledberg, 2020). As there are also temporal trends in mortality (increased life expectancy), the average mortality estimation cannot use too many years (Ledberg, 2020).Absence of SARS-CoV-2 antibodies in pre-pandemic plasma from children and adults in Vietnam
We tested pre-pandemic (2015–-2019) plasma samples from 148 Vietnamese children and 100 Vietnamese adults at high risk of zoonotic infections for antibodies against SARS-CoV-2 nucleocapsid and spike proteins. None was positive. The data thus demonstrated no evidence of prior serological cross-reactivity with SARS-CoV-2 that might explain the low numbers of COVID-19 in Vietnam. No pre-existing cross-reactivity might explain Vietnam success of COVID-19 control.Reduction in COVID-19 prevalence in healthcare workers in a university hospital in southern Brazil after the start of vaccination
There is evidence that vaccines are able to reduce infection and the number of more severe cases of COVID-19 (Bradley et al., 2021; Keehner et al., 2021; Daniel et al., 2021; Benenson et al., 2021). The P1 variant of SARS-CoV-2 is refractory to multiple neutralizing monoclonal antibodies (Wang et al., 2021). This may lead to antigen alterations that impair vaccine protection, leading to a diagnosis of infection in individuals in whom vaccine efficacy has been demonstrated (Wang et al., 2021).High seroprevalence for SARS-CoV-2 infection in South America, but still not enough for herd immunity!
There has been intense discussion about the importance of reaching herd immunity to achieve global population protection status against SARS-CoV-2/COVID-19. For that reason, vaccination coverage and seroprevalence studies are increasing around the world; some of them have shown an increase in the seroprevalence of different populations. For example, a recent study in Jordan (Sughayer et al., 2021) stated the importance of seroprevalence studies for SARS-CoV-2 infection among healthy blood donors.Incidence of SARS-CoV-2 infection in health care workers from Northern Italy based on antibody status: immune protection from secondary infection- A retrospective observational case-controlled study
Natural SARS-CoV-2 infection elicits humoral (Percivalle et al., 2020; Ni et al., 2020; Muecksch et al., 2021) and cellular responses (Grifoni et al., 2020). However, little is known about protection against secondary infection. Recently, a longitudinal study conducted in the United Kingdom (Lumley et al., 2021) showed that SARS-CoV-2 seropositivity was associated with a lower SARS-CoV-2 RNA detection rate.Drug exposure may have a substantial influence on COVID-19 prognosis among residents of long-term care facilities: an exploratory analysis
Older people living in long-term care (LTC) facilities have been the population hardest hit by the Covid-19 pandemic. Recent estimates suggest that as much as 47% of first-wave Covid-19 fatalities in Western countries occurred in LTC facilities. (Comas-Herrera et al., 2020) This appalling statistic is related to the combination of optimal epidemiological conditions for the spread of SARS-CoV-2 in enclosed spaces crowded with a highly vulnerable population. One feature of this population that has received scant attention in this connection is drug consumption.Evaluation of potassium peroxymonosulfate (MPS) efficacy against SARS-CoV-2 virus using RT-qPCR-based method
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spreads mostly through respiratory droplets, and the inhalation of these droplets is the main route of transmission leading to the fatal coronavirus disease 2019 (COVID-19) (Wang et al., 2020). Contact with contaminated fomites has been proposed as another possible route of viral transmission. Recently, the survival of SARS-CoV-2 on different surfaces has been assessed. The virus can remain viable for at least 3 hours in the air post-aerosolization, for 24 hours on cardboard, and for up to 2–3 days on domestic materials like plastic and stainless steel (van Doremalen et al., 2020).Relative risks of COVID-19 fatality between the first and second waves of the pandemic in Ontario, Canada
The COVID-19 pandemic continues to surge globally. Recently, many countries experienced a substantial second wave of COVID-19 (James et al., 2021). While there were much higher infection numbers and in some countries more deaths than those in the first wave, a substantial decrease in the case fatality rate (CFR) was observed ( https://www.ft.com/content/b3801b63-fbdb-433b-9a46-217405b1109f ). Interestingly, researchers have reported that CFR decreased during the first wave indicating that COVID-19 severity might lessen with time (Schmidt et al., 2021; Anesi et al., 2021).Danish citizens’ preferences for at-home oropharyngeal/nasal SARS-CoV-2 specimen collection
Since its emergence, SARS-CoV-2 causing COVID-19 has infected more than 179 million persons (World Health Organization, 2021). The gold standard for diagnostic confirmation of SARS-CoV-2 is reverse transcriptase-polymerase chain reaction (RT-PCR) using nasopharyngeal specimens collected by a swab. We (Therchilsen et al., 2020) and others (Tu et al., 2020) have found that self-collection of SARS-CoV-2 specimens is a reliable method compared with healthcare worker (HCW) collected samples with acceptable agreement of Cohens kappa 0.82 and without any significant difference in diagnostic sensitivity (84.2% and 89.5%, respectively, P = 0.81).Countries with similar COVID-19 vaccination rates yet divergent outcomes: are all vaccines created equal?
With the race to vaccinate the world against SARS-CoV-2 well on its way, many countries have already achieved impressive vaccination rates and are quickly reaping the benefits. However, not all highly vaccinated populations are seeing the same results. A striking example of such divergent outcomes is currently being seen in the neighboring states of Qatar and Bahrain. In an impressive feat, both nations have vaccinated more than 50% of their population. However, while in Qatar, infection rates have decreased, infection rates have increased to unprecedented and alarming levels in Bahrain (Figure 1).Preparing for the next pandemic: Lessons from rapid scale-up of SARS-CoV-2 testing in a South African high-throughput automated HIV molecular laboratory
Africa’s initial readiness to respond to the SARS-CoV-2 pandemic was questioned due to reliance on rapid turnaround-time (TAT) of polymerase chain reaction (PCR) results for clinical management, isolation and quarantine decisions. The National Health Laboratory Service (NHLS) HIV Molecular Laboratory in Johannesburg, South Africa, is one of the largest automated HIV laboratories worldwide, performing 1.2 million HIV viral load (HIVVL) tests annually. Despite extensive experience in managing high volumes, significant challenges were encountered during the rapid transition to large-scale SARS-CoV-2 testing.Using serological studies to assess COVID-19 infection fatality rate in developing countries: A case study from one Colombian department
The infection fatality rate (IFR) is a critical epidemiological parameter that allows assessment of the dynamics and virulence of any infectious agent and the quality of health services (Levin et al., 2020). There is still uncertainty about the true IFR of COVID-19 because detecting all infections and cases depends on the quality of surveillance and the number of tests available. Attempting to estimate IFR in developing countries is incredibly challenging because they have weaker surveillance systems coupled with a deficit of laboratories able to carry out molecular tests across the entire territory.SARS-CoV-2 infection in fully vaccinated healthcare workers
The BNT162b2 mRNA COVID-19 vaccine has shown optimal protection in humans against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) (Polack et al., 2020); this vaccine generates codification of the spike protein with high levels of immunity. In 2020, Yu et al. reported infections after exposure to SARS-CoV-2 in fully vaccinated monkeys; however, these animals showed much lower viral loads compared with the unvaccinated control group, suggesting correlation between neutralizing antibody levels of post-vaccine serum and protection against SARS-CoV-2.Parallel detection of SARS-CoV-2 RNA and nucleocapsid antigen in nasopharyngeal specimens from a COVID-19 patient screening cohort
The ongoing pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) poses serious challenges for healthcare. Unprecedented demands on molecular testing have revealed a number of practical limitations of the PCR-based COVID-19 diagnostics. In this situation, additional and less demanding laboratory tools for SARS-CoV-2 detection, such as testing for viral antigens, merit consideration. A series of studies have reported the performance of numerous qualitative immunochromatographic rapid diagnostic tests (Young et al., 2020; Chaimayo et al., 2020; Lanser et al., 2020), as well as several variants of automated quantitative assays (Hirotsu et al., 2021; Pollock et al., 2021).Underreporting of race/ethnicity in COVID-19 research
Recent discourse against structural racism has reminded us of how far we are from what was considered “a self-evident truth, equality.” Regrettably, medicine has not been impervious to these social dynamics. While disparities in healthcare are well-described, the disparate burden of SARS-CoV-2 infection (COVID-19) on racial minorities has laid bare a system long afflicted with inequities (Killerby et al., 2020; Krishnan et al., 2020). Historically, race/ethnicity has been inadequately reported in clinical studies (Cooper et al., 2018; Loree et al., 2019).Determinants of the protective effect of glucocorticoids on mortality in hospitalized patients with COVID-19: Insights from the Cardio-COVID-Italy multicenter study
Coronavirus disease 2019 (COVID-19) is a global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and represents a major cause of morbidity and mortality worldwide (Wiersinga et al., 2020). Systemic glucocorticoids have emerged as an effective therapeutic option in hospitalized patients with COVID-19, especially in cases of moderate-severe acute respiratory distress syndrome or need of respiratory support (RECOVERY Collaborative Group et al., 2021; Tomazini et al., 2020; WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group et al., 2020).Immunological memory and neutralizing activity to a single dose of COVID-19 vaccine in previously infected individuals
The ongoing COVID-19 pandemic caused by SARS-CoV-2 has resulted in unprecedented mortality and morbidity globally. In the absence of specific therapeutic drugs to treat COVID-19, vaccines are currently the only option to control SARS-CoV-2 infection (Krammer, 2020). COVID-19 vaccination programs initiated worldwide have reduced disease severity (Rinott et al., 2021). Vaccinating huge populations require evidence-based strategies for successful implementation to control the pandemic. Although individuals who have had COVID-19 have been shown to have a higher antibody response to a single dose of mRNA vaccine than non-exposed individuals (Krammer et al., 2021; Saadat et al., 2021), their efficacy to generate immunological memory and protection against reinfection of SARS-CoV-2 is not yet reported.Non-ABO red cell antibodies and risk of COVID-19
It is not known whether non-ABO antibodies confer any protective effect against SARS-CoV-2 infection or COVID-19 severe illness alone or in conjunction with O blood group. This cohort study included 413 576 persons in Ontario, Canada with known ABO blood group and non-ABO antibody screen status, who subsequently underwent SARS-CoV-2 viral RNA polymerase chain reaction testing between January and November 2020. The risk of SARS-CoV-2 infection or COVID-19 severe illness was not associated with the presence of non-ABO antibodies, even among persons with O blood group.Changing influenza activity in the Southern hemisphere countries during the COVID-19 pandemic
The decrease in influenza activity in the Northern hemisphere in 2020 has been widely reported (Itaya et al., 2020; World Health Organization, 2021). However, previous studies analysing influenza activity in 2020 in the Southern hemisphere have several limitations, such as not comparing influenza transmission dynamics in 2020 with those of previous years (Olsen et al., 2020), not including all the weeks of the study year (Olsen et al., 2020; Sullivan et al., 2020), and focusing on single countries (Sullivan et al., 2020).Single-dose BNT162b2 mRNA COVID-19 vaccine significantly boosts neutralizing antibody response in health care workers recovering from asymptomatic or mild natural SARS-CoV-2 infection
While there is consensus that mass vaccination is the key strategy to keep the current SARS-CoV-2 pandemic under control, the need to vaccinate those who have recovered from natural infection is still under debate. Several countries have been vaccinating previously infected people, and this group has not been excluded from the main vaccine field trials (Krammer et al., 2021; Saadat et al., 2021; Manisty et al., 2021), although placing them lower on the vaccination priority list has been suggested (www.has-sante.fr accessed on March 31, 2021).Test-based de-isolation in COVID-19 immunocompromised patients: Cycle threshold value versus SARS-CoV-2 viral culture
With the ongoing coronavirus disease 19 (COVID-19) pandemic, an increasing number of immunocompromised patients are becoming infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) worldwide, including solid organ transplant recipients (Elias et al., 2020). Immunocompromised patients may have prolonged viral shedding and thus may be unrecognized sources of SARS-CoV-2 transmission (Baang et al., 2021). It has been reported that critically ill patients have positive infectious SARS-CoV-2 cultures for 20 days, while those with mild disease have positive viral cultures for 8–10 days post infection (van Kampen et al., 2021; Wölfel et al., 2020).Post-vaccination cases of COVID-19 among healthcare workers at Siloam Teaching Hospital, Indonesia
Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has rapidly spread worldwide. Indonesia reported its first case of COVID-19 on 2 March 2020, and reached more than 1 million cases by February 2021 (World Health Organization, 2021). Among the countries in south-east Asia, Indonesia has the most active COVID-19 cases (Dong et al., 2020), and the nation’s case fatality rate was higher than the global average (2.7% vs 2.2%) at the end of February 2021 (Kementerian Kesehatan Republik Indonesia, 2021).The initial impact of a national BNT162b2 mRNA COVID-19 vaccine rollout
A two-dose regimen of BNT162b2, the Pfizer-BioNTech COVID-19 mRNA vaccine, was shown to reduce the risk of SARS-CoV-2 by around 95% in a randomized clinical trial and in a mass national vaccination program (Dagan et al., 2021; Polack et al., 2020). On 23 December 2020, Qatar started a national BNT162b2 rollout programme, in addition to existing COVID-19 public health control measures. The rollout initially prioritised healthcare workers, individuals aged ≥50 years, and those with chronic or immunosuppressive medical conditions.Tracking COVID-19 with wastewater to understand asymptomatic transmission
The primary mode of transmission of SARS-CoV-2 is via respiratory droplets that people produce when they cough, sneeze or exhale (Hu et al., 2021). A significant proportion of patients with SARS-CoV-2 were reported to have diarrhea in addition to respiratory symptoms (Han et al., 2020, 2021). Several reports have shown that RNA of SARS-CoV-2 can be detected in wastewater samples, and shedding of SARS-CoV-2 was routinely monitored in several countries to predict outbreaks during the ongoing COVID-19 pandemic and as early warning systems (Medema et al., 2020; Peccia et al., 2020; Wu et al., 2020).Impact of COVID-19 on immunization of Brazilian infants
The first case of coronavirus disease 2019 (COVID-19) in Brazil, a country of 212 million inhabitants, was diagnosed on 26 February 2020. As of 2 March 2021, 10.65 million cases have been registered and 257,562 people have died ( https://covid.saude.gov.br/ ). In addition to the profound economic impact of the social isolation measures adopted to face infection with severe acute respiratory syndrome coronavirus-2 infection, COVID-19 affected the entire healthcare network. Decreased vaccination coverage and the emergence of vaccine-preventable diseases (VPDs) have been reported, particularly in poor and developing countries (Adamu et al., 2020; McDonald et al., 2020; Zhong et al., 2021).Performance of SARS-CoV-2 rapid antigen test compared with real-time RT-PCR in asymptomatic individuals
Given the increase in cases of SARS-CoV-2 infections worldwide, there is a need for a reliable rapid diagnostic test in addition to existing gold standard real-time RT-PCR. Rapid antigen tests (RAT) for SARS-CoV-2 can be performed onsite in mass testing, are inexpensive compared to real-time RT-PCR, do not require specific and expensive equipment, and the results are available within 15 min (CDC, 2021), which could serve to evaluate chains of infection and their interruption. A recent meta-analysis revealed that the average sensitivity and specificity of RAT for SARS-CoV-2 were 56.2% and 99.5%, respectively (Dinnes et al., 2020).Third wave of COVID-19 in Madrid, Spain
Madrid has been the epicenter of COVID-19 in Spain, primarily due to its high population density and mobility. The city has 3.3 million people, with 6.8 million across the metropolitan area. Up to March 15 2021, roughly 605 000 persons had been diagnosed with SARS-CoV-2 infection and 14 000 had died in the Madrid region (Ministerio de Sanidad, 2021; Instituto Nacional de Estadística, 2021). These figures refer to laboratory-confirmed cases, which underestimate the true number as testing access was limited during the earlier stages of the pandemic (Soriano and Barreiro, 2020).Effect of Ammonium Chloride in addition to standard of care in outpatients and hospitalized COVID-19 patients: A randomized clinical trial
Coronavirus disease 2019 (COVID-19) is an acute respiratory illness caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), first identified in December 2019 (Helmy et al., 2020), and has resulted in the death of 1.3 million people (WHO, 2020). Based on preclinical studies, Quaternary ammonium compounds such as Ammonium Chloride have been reported to have broad-spectrum antiviral activities and may hold therapeutic value against COVID-19 (Kargar Kheirabad and Nourozi, 2020; Baker et al., 2020).Comparative analysis of antigen and molecular tests for the detection of Sars-CoV-2 and related variants: A study on 4266 samples
The pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (Sars-CoV-2) dramatically affects health and quality of life worldwide (Strafella et al., 2020a,b). To date, the gold standard test for Coronavirus-19 disease (COVID-19) diagnosis is represented by Real Time PCR (RT-PCR), which detects viral genome with high-sensitivity in naso-oropharyngeal swab fluids (Pascarella et al., 2020; Wiersinga et al., 2020). However, preanalytical and analytical issues, including long turnaround time, limit its use in specialized laboratories.First case of postmortem study in a patient vaccinated against SARS-CoV-2
We report on an 86-year-old male resident of a retirement home who received vaccine against SARS-CoV-2. Past medical history included systemic arterial hypertension, chronic venous insufficiency, dementia and prostate carcinoma. On January 9, 2021, the man received lipid nanoparticle-formulated, nucleoside-modified RNA vaccine BNT162b2 in a 30 μg dose. On that day and in the following 2 weeks, he presented with no clinical symptoms (Table 1). On day 18, he was admitted to hospital for worsening diarrhea.
