ABSTRACT
Background Healthcare workers have experienced high rates of morbidity and mortality from COVID-19. Methods We conducted a prospective cohort study in three Albanian hospitals between February 19 and December 14, 2021. All participants underwent PCR and serology testing at enrolment, regular serology throughout, and PCR testing when symptomatic. We estimated vaccine effectiveness (VE) against COVID-19, and against all SARS-CoV-2 infections (symptomatic or asymptomatic). VE was estimated using a Cox regression model, with vaccination status as a time-varying variable. Findings We enrolled 1504 HCWs;70% had evidence of prior SARS-CoV-2 infection. VE against COVID-19 was 65·1% (95% CI 37·7–80·5);58·2% (95% CI 15·7–79·3) among participants without prior SARS-CoV-2 infection;and 73·6% (95% CI 24·3–90·8) among previously-infected participants. For BNT162b2 only, VE was 69·5% (95% CI 44·5–83·2). During the Delta variant-predominant period, VE was 67·1% (95% CI 38·3–82·5). VE against SARS-CoV-2 infection for the full study period was 36·9% (95% CI 15·8–52·7). Interpretation We found moderate primary-series VE against COVID-19 among healthcare workers in Albania. Our results support the continued promotion of COVID-19 vaccine in Albania, and highlight the benefit of vaccination in populations with high levels of prior infection.
ABSTRACT
Background Healthcare workers (HCWs) have been disproportionally affected by COVID-19. We investigated factors associated with two- and three-dose COVID-19 vaccine uptake and SARS-CoV-2 seropositivity among 1504 HCWs enrolled (19 February-7 May 2021) in a prospective COVID-19 vaccine effectiveness cohort in Albania through a secondary analysis. Methods We collected sociodemographic, occupational, health, prior SARS-CoV-2 infection, and COVID-19 vaccination data from all HCWs at enrollment. Vaccination status was assessed weekly through June 2022. A serum sample was collected from all participants at enrollment and tested for anti-spike SARS-CoV-2 antibodies. We analyzed HCWs characteristics and outcomes using multivariable logistic regression. Findings By 11 June 2022, 1337 (88.9%) HCWs had received two COVID-19 vaccine doses, of whom 255 (19.1%) received a booster. Factors significantly associated with receiving three doses (adjusted odds ratio (aOR), 95% CIs) were being ≥35 years (35–44 years: 1.76 (1.05–2.97);45–54 years: 3.11 (1.92–5.05);≥55 years: 3.38 (2.04–5.59)) and vaccinated against influenza (1.78;1.20–2.64). Booster dose receipt was lower among females (0.58;0.41–0.81), previously infected (0.67;0.48–0.93), nurses and midwives (0.31;0.22–0.45), and support staff (0.19;0.11–0.32). Overall 1076 (72%) were SARS-CoV-2 seropositive at enrollment. Nurses and midwifes (1.45;1.05–2.02), support staff (1.57;1.03–2.41), and HCWs performing aerosol-generating procedures (AGPs) (1.40;1.01–1.94) had higher odds of being seropositive, while smokers had reduced odds (0.55;0.40–0.75). Interpretation In a large cohort of Albanian HCWs, COVID-19 vaccine booster dose uptake was very low, particularly among younger, female, and non-physician HCWs, despite evidence demonstrating the added benefit of boosters in preventing infection and severe disease. Reasons behind these disparities should be explored to develop targeted strategies in order to promote uptake in this critical population. SARS-CoV-2 seroprevalence was higher among non-physicians and HCWs performing APGs. A better understanding of the factors contributing to these differences is needed to inform interventions that could reduce infections in the future. Funding This study was funded by the Task Force for 10.13039/100006090Global Health (10.13039/100000030US Centers for Disease Control (CDC) cooperative agreement # NU51IP000873) and the World Health Organization, Regional Office for Europe.
ABSTRACT
Background: Healthcare workers (HCWs) have been disproportionally affected by COVID-19. We investigated factors associated with two- and three-dose COVID-19 vaccine uptake and SARS-CoV-2 seropositivity among 1504 HCWs enrolled (19 February-7 May 2021) in a prospective COVID-19 vaccine effectiveness cohort in Albania through a secondary analysis. Methods: We collected sociodemographic, occupational, health, prior SARS-CoV-2 infection, and COVID-19 vaccination data from all HCWs at enrollment. Vaccination status was assessed weekly through June 2022. A serum sample was collected from all participants at enrollment and tested for anti-spike SARS-CoV-2 antibodies. We analyzed HCWs characteristics and outcomes using multivariable logistic regression. Findings: By 11 June 2022, 1337 (88.9%) HCWs had received two COVID-19 vaccine doses, of whom 255 (19.1%) received a booster. Factors significantly associated with receiving three doses (adjusted odds ratio (aOR), 95% CIs) were being ≥35 years (35-44 years: 1.76 (1.05-2.97); 45-54 years: 3.11 (1.92-5.05); ≥55 years: 3.38 (2.04-5.59)) and vaccinated against influenza (1.78; 1.20-2.64). Booster dose receipt was lower among females (0.58; 0.41-0.81), previously infected (0.67; 0.48-0.93), nurses and midwives (0.31; 0.22-0.45), and support staff (0.19; 0.11-0.32). Overall 1076 (72%) were SARS-CoV-2 seropositive at enrollment. Nurses and midwifes (1.45; 1.05-2.02), support staff (1.57; 1.03-2.41), and HCWs performing aerosol-generating procedures (AGPs) (1.40; 1.01-1.94) had higher odds of being seropositive, while smokers had reduced odds (0.55; 0.40-0.75). Interpretation: In a large cohort of Albanian HCWs, COVID-19 vaccine booster dose uptake was very low, particularly among younger, female, and non-physician HCWs, despite evidence demonstrating the added benefit of boosters in preventing infection and severe disease. Reasons behind these disparities should be explored to develop targeted strategies in order to promote uptake in this critical population. SARS-CoV-2 seroprevalence was higher among non-physicians and HCWs performing APGs. A better understanding of the factors contributing to these differences is needed to inform interventions that could reduce infections in the future. Funding: This study was funded by the Task Force for Global Health (US Centers for Disease Control (CDC) cooperative agreement # NU51IP000873) and the World Health Organization, Regional Office for Europe.