Coronavirus (COVID-19) Collection
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).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.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.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).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.Interim estimates in null models of COVID-19 vaccine effectiveness
In the international race for vaccines against COVID-19 significant progress has been claimed recently, with Pfizer Inc. (New York, NY, USA) reporting an interim analysis from their current phase 3 clinical trials of an RNA-based vaccine candidate (Pfizer, 2020; Polack et al., 2020). From this placebo-controlled, randomized and observer-blind study, vaccine effectiveness (VE) of >90% has been reported based on a preliminary number of 94 confirmed cases of symptomatic SARS-CoV-2 infections accrued over 104 days (between July 27 and November 8, 2020).
