Municipal Health Department of Rio de Janeiro, Rio de Janeiro City Government, Rio de Janeiro, Brazil.
National Institute of Infectious Disease Evandro Chagas, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil.
Front Public Health. 2022 Nov 14;10:1017337. doi: 10.3389/fpubh.2022.1017337. eCollection 2022.
A vaccination campaign targeted adults in response to the pandemic in the City of Rio de Janeiro.
We aimed to evaluate the seroprevalence of SARS-CoV-2 antibodies and identify factors associated with seropositivity on vaccinated and unvaccinated residents.
We performed a seroepidemiologic survey in all residents of Paquetá Island, a neighborhood of Rio de Janeiro city, during the COVID-19 vaccine roll-out. Serological tests were performed from June 16 to June 19, 2021, and adjusted seropositivity rates were estimated by age and epidemiological variables. Logistic regression models were used to estimate adjusted ORs for risk factors to SARS-CoV-2 seropositivity in non-vaccinated individuals, and potential determinants of the magnitude of antibody responses in the seropositive population.
We included in the study 3,016 residents of Paquetá (83.5% of the island population). The crude seroprevalence of COVID-19 antibodies in our sample was 53.6% (95% CI = 51.0, 56.3). The risk factors for SARS-CoV-2 seropositivity in non-vaccinated individuals were history of confirmed previous COVID-19 infection (OR = 4.74; 95% CI = 3.3, 7.0), being a household contact of a case (OR = 1.93; 95% CI = 1.5, 2.6) and in-person learning (OR = 2.01; 95% CI = 1.4, 3.0). Potential determinants of the magnitude of antibody responses among the seropositive were hybrid immunity, the type of vaccine received, and time since the last vaccine dose. Being vaccinated with Pfizer or AstraZeneca (Beta = 2.2; 95% CI = 1.8, 2.6) determined higher antibody titers than those observed with CoronaVac (Beta = 1.2; 95% CI = 0.9, 1.5).
Our study highlights the impact of vaccination on COVID-19 collective immunity even in a highly affected population, showing the difference in antibody titers achieved with different vaccines and how they wane with time, reinforcing how these factors should be considered when estimating effectiveness of a vaccination program at any given time. We also found that hybrid immunity was superior to both infection-induced and vaccine-induced immunity alone, and online learning protected students from COVID-19 exposure.
为应对里约热内卢市的大流行，一项针对成年人的疫苗接种运动已经展开。
我们旨在评估 SARS-CoV-2 抗体的血清阳性率，并确定与接种和未接种居民的血清阳性相关的因素。
我们在 COVID-19 疫苗接种期间对里约热内卢市一个街区帕凯阿岛的所有居民进行了血清流行病学调查。血清学检测于 2021 年 6 月 16 日至 6 月 19 日进行，按年龄和流行病学变量估计调整后的血清阳性率。使用逻辑回归模型估计非接种个体中 SARS-CoV-2 血清阳性的危险因素调整比值比（OR），以及血清阳性人群中抗体反应幅度的潜在决定因素。
我们共纳入了 3016 名帕凯阿岛居民（占该岛人口的 83.5%）。我们样本中的 COVID-19 抗体总血清阳性率为 53.6%（95%CI=51.0，56.3）。非接种个体中 SARS-CoV-2 血清阳性的危险因素包括既往确诊 COVID-19 感染史（OR=4.74；95%CI=3.3，7.0）、与病例有家庭接触（OR=1.93；95%CI=1.5，2.6）和面对面学习（OR=2.01；95%CI=1.4，3.0）。血清阳性人群中抗体反应幅度的潜在决定因素包括混合免疫、所接种疫苗的类型以及最后一剂疫苗接种后的时间。与接种科兴或阿斯利康（Beta=2.2；95%CI=1.8，2.6）相比，接种辉瑞或阿斯利康（Beta=1.2；95%CI=0.9，1.5）的抗体滴度更高。
我们的研究强调了疫苗接种对 COVID-19 群体免疫力的影响，即使在受影响程度很高的人群中也是如此，表明不同疫苗产生的抗体滴度不同，且随着时间的推移而减弱，这进一步证明了在任何特定时间评估疫苗接种计划的有效性时，都应考虑这些因素。我们还发现，混合免疫优于单纯感染诱导或疫苗诱导免疫，在线学习使学生免受 COVID-19 暴露。
