Sars-cov-2 immunity in albania: lessons from the covid-19 pandemic for future public health and environmental challenges
Year: 2026
Type: article
Study design: Observational Study
Abstract: The COVID-19 pandemic posed a significant public health stressor, necessitating a robust understanding of SARS-CoV-2 transmission dynamics and the longitudinal evolution of population immunity. This study evaluates anti-SARS-CoV-2 seroprevalence in Tirana, Albania, from 2020 to 2023, quantifying the relative contributions of natural infection, vaccination, and hybrid immunity. Five cross-sectional serosurveys were conducted (June 2020–April 2023) among adults aged 18–70 years. Participants were randomly selected from five primary urban healthcare centers. Serological status was determined via enzyme-linked immunosorbent assays (ELISA) detecting IgG antibodies against SARS-CoV-2 spike (S1) and nucleoprotein (N) antigens. Anti-S1 IgG seroprevalence escalated from 7.5% in June 2020 to 48.2% by December 2020. Prevalence reached 71.7% in August 2021, and plateaued at 93.1% in August 2022 and 93.9% by April 2023. Notably, hybrid immunity prevalence surged from 19.9% in 2021 to 56.0% in 2022. Mean antibody titers in 2022 were 2.4-fold higher than in 2021, indicating a potent immune response synergized by vaccination and prior infection. By late 2022, the Albanian urban population reached a high immunity threshold, primarily driven by the expansion of hybrid immunity. While these levels suggest a transition toward endemicity, targeted vaccination remains critical for vulnerable cohorts. This study provides a framework for long-term serological surveillance and informs future immunization strategies in similar epidemiological settings.
Language: English
Subfield: Infectious Diseases
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7168170607