ArticleCroatian medical journal2021
Waning immunity six months after BioNTech/Pfizer COVID-19 vaccination among nursing home residents in Zagreb, Croatia.
Article in Croatian medical journal, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.
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Who cites it
14 citing papers in PubMed, 19 citations in OpenAlex.
- Article
- Dynamics of SARS-CoV-2 IgG in Nursing Home Residents in Belgium Throughout Three BNT162b2 Vaccination Rounds: 19-Month Follow-Up.Vaccines · 2025Article
- Use of a point-of-care test to rapidly assess levels of SARS-CoV-2 nasal neutralising antibodies in vaccines and breakthrough infected individuals.Scientific reports · 2023Article
- Neutralizing Activity of SARS-CoV-2 Antibodies in Patients with COVID-19 and Vaccinated Individuals.Antibodies (Basel, Switzerland) · 2023Article
- Incidence, Risk Factors and Mortality Associated with Major Bleeding Events in Hospitalized COVID-19 Patients.Life (Basel, Switzerland) · 2023Article
- Vaccine uptake in caregivers family members and patients with dementia and relationship with severity of dementia and caregiver burden: a cross-sectional study.Aging clinical and experimental research · 2023Article
- Predictors of prolonged hospitalization of COVID-19 patients.European geriatric medicine · 2023Article
- Detection of SARS-CoV-2 Antibodies: Comparison of Enzyme Immunoassay, Surrogate Neutralization and Virus Neutralization Test.Antibodies (Basel, Switzerland) · 2023Article
- The performance of the WHO COVID-19 severity classification, COVID-GRAM, VACO Index, 4C Mortality, and CURB-65 prognostic scores in hospitalized COVID-19 patients: data on 4014 patients from a tertiary center registry.Croatian medical journal · 2023Article
- Real-life experience with remdesivir for treatment of hospitalized coronavirus disease 2019 patients: matched case-control study from a large tertiary hospital registry.Croatian medical journal · 2022Article
- Managing the Impact of COVID-19 in Nursing Homes and Long-Term Care Facilities: An Update.Journal of the American Medical Directors Association · 2022Article
- How Does Vaccination against SARS-CoV-2 Affect Hospitalized Patients with COVID-19?Journal of clinical medicine · 2022Article
- Unpacking the Implications of SARS-CoV-2 Breakthrough Infections on COVID-19 Vaccination Programs.Vaccines · 2022Article
- Waning immunity to SARS-CoV-2 following vaccination or infection.Frontiers in medicine · 2022Article
Corrections and comments
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Authors and funding
4 authors at 4 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
aimTo assess the humoral immunity to COVID-19 in nursing home residents six months after vaccination.
methodsThis seroepidemiological research enrolled 118 residents of one nursing home in Zagreb. All participants received two doses of BioNTech/Pfizer COVID-19 and had no previously detected SARS-CoV-2 infection. The samples were tested for the presence of neutralizing antibodies using a virus neutralization test. A SARS-CoV-2 strain isolated in Vero E6 cells from a Croatian COVID-19 patient was used as a stock virus. Neutralizing antibody titer was defined as the reciprocal of the highest serum dilution that showed at least 50% neutralization. Neutralizing antibody titer ≥8 was considered positive.
resultsSixty-four (54%) participants had a positive neutralizing antibody titer, 27 (23%) had a low positive titer (titer 8), and 27 (23%) had a negative titer. Women had a significantly higher median titer than men (16 [interquartile range, IQR 24] vs 8 [IQR 12], Mann-Whitney U=1033, P=0.003). Age was negatively but not significantly correlated with neutralizing antibody titer (Spearman's rho -0.132, P=0.155).
conclusionAlmost half of the participants (46%) had a negative or low positive titer six months after having been fully vaccinated. This study suggests that humoral immunity among nursing home residents considerably wanes six months after BioNTech/Pfizer COVID-19 vaccination. Our results could contribute to the discussion about the need for a booster dose.
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Identifiers
34981696PMC8771239W4206896195What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.