ABSTRACT
Background: The correlate(s) of protection against SARS-CoV-2 remain incompletely de-fined. Additional information regarding the combinations of antibody and T cell-mediated immunity which can protect against (re)infection are needed. Methods: We conducted a population-based, longitudinal cohort study including 1044 individuals of varying SARS-CoV-2 vaccination and infection statuses. We assessed Spike (S)- and Nucleocapsid (N)-IgG and wildtype, delta, and omicron neutralizing antibodies. In a subset of 328 individuals, we evaluated S, Membrane (M) and N-specific T cells. 3 months later, we reassessed antibody (n=964) and T cell (n=141) responses and evaluated factors associated with protection from (re)infection. Results: At study start, >98% of participants were S-IgG seropositive. N-IgG and M/N-T cell responses increased over time, indicating viral (re)exposure, despite existing S-IgG. Com-pared to N-IgG, M/N-T cells were a more sensitive measure of viral exposure. N-IgG titers in the top 33% of participants, omicron neutralizing antibodies in the top 25%, and S-specific T cell responses were all associated with reduced likelihood of (re)infection over time. Conclusions: Population-level SARS-CoV-2 immunity is S-IgG-dominated, but heterogenous. M/N T cell responses can distinguish previous infection from vaccination, and monitoring a combination of N-IgG, omicron neutralizing antibodies and S-T cell responses may help estimate protection against SARS-CoV-2 (re)infection.
Subject(s)
COVID-19 , Poult Enteritis Mortality SyndromeABSTRACT
Importance Long-term control of SARS-CoV-2 requires effective vaccination strategies. This has been challenged by public mistrust and spread of misinformation regarding vaccine safety. Hence, better understanding and communication on the longer-term and comparative experiences of general population individuals following SARS-CoV-2 vaccination are required. Objective To evaluate and compare self-reported adverse effects following SARS-CoV-2 vaccination, participants’ perceptions regarding vaccinations and their compliance with recommended public health measures. Design, Setting and Participants Population-based longitudinal cohort of 575 adults, randomly selected from all individuals presenting to the reference vaccination center of the Canton of Zurich, Switzerland, for receipt of BNT162b2, mRNA1273, or JNJ-78436735. Exposures BNT162b2, mRNA1273, or JNJ-78436735 vaccines. Main Outcomes and Measures Primary outcomes included period prevalence, onset, duration, and severity of self-reported adverse effects over 12 weeks following vaccination with a specific focus on the proportion of participants reporting allergic reactions, menstrual irregularities, or cardiac adverse effects, or requiring hospitalization. Secondary outcomes included risk factors associated with reporting adverse effects, perception of vaccine importance, trust in public health authorities and pharmaceutical companies, and compliance with recommended public health measures. Results 454 (79.0%) participants reported at least one adverse effect during 12 weeks after vaccination. Prevalence was highest among mRNA-1273 recipients (88.7% vs. 77.3% after BNT162b2, 69.1% after JNJ-78436735). Most adverse effects were systemic (72%), occurred within 24 hours (67.9%), and resolved in less than three days (76.3%). 85.2% were reported as mild or moderate. Allergic reactions were reported by 0.4% of participants, hospitalizations by 0.7%, cardiac adverse effects by 1.4%. Menstrual irregularities were reported by 9% of female participants younger than 50 years. Female sex, younger age, higher education, and receipt of mRNA-1273 were associated with reporting adverse effects. Compared to JNJ-78436735 recipients, a higher proportion of mRNA vaccine recipients agreed that vaccination is important (87.5% vs. 28.5%), and trusted public health authorities (80.2% vs. 30.3%) and pharmaceutical companies (71.7% vs. 23.6%). Conclusions and Relevance Our population-based cohort provided real-world data on self-reported adverse effects following SARS-CoV-2 vaccination and highlights the importance of transparent communication regarding adverse effects and building trust in public health authorities to ensure successful future vaccination campaigns. Main Points Our representative population-based cohort study demonstrated the safety of three SARS-CoV-2 vaccines and provides real-world estimates on adverse effect incidence.Transparent communication of expected adverse effects to vaccine-seeking individuals is pivotal to build trust in current or future vaccination campaigns.
ABSTRACT
Background Longer-term consequences after SARS-CoV-2 infection are becoming an important burden to societies and healthcare systems. Data on post-COVID-19 syndrome in the general population are required for the timely planning of healthcare services and resources. The objective of this study was to assess the prevalence of impaired health status and physical and mental health symptoms among individuals at least six months after SARS-CoV-2 infection, and to characterize their healthcare utilization. Methods This population-based prospective cohort study (Zurich SARS-CoV-2 Cohort) enrolled 431 adults from the general population with polymerase chain reaction-confirmed SARS-CoV-2 infection reported to health authorities between 27 February 2020 and 05 August 2020 in the Canton of Zurich, Switzerland. We evaluated the proportion of individuals reporting not to have fully recovered since SARS-CoV-2 infection, and the proportion reporting fatigue (Fatigue Assessment Scale), dyspnea (mMRC dyspnea scale) or depression (DASS-21) at six to eight months after diagnosis. Furthermore, the proportion of individuals with at least one healthcare contact after their acute illness was evaluated. Multivariable logistic regression models were used to assess factors associated with these main outcomes. Results Symptoms were present in 385 (89%) participants at diagnosis and 81 (19%) were initially hospitalized. At six to eight months, 111 (26%) reported not having fully recovered. 233 (55%) participants reported symptoms of fatigue, 96 (25%) had at least grade 1 dyspnea, and 111 (26%) had DASS-21 scores indicating symptoms of depression. 170 (40%) participants reported at least one general practitioner visit related to COVID-19 after acute illness, and 10% (8/81) of initially hospitalized individuals were rehospitalized. Individuals that have not fully recovered or suffer from fatigue, dyspnea or depression were more likely to have further healthcare contacts. However, a third of individuals (37/111) that have not fully recovered did not seek further care. Conclusions In this population-based study, a relevant proportion of participants suffered from longer-term consequences after SARS-CoV-2 infection. With millions infected across the world, our findings emphasize the need for the timely planning of resources and patient-centered services for post-COVID-19 care. Registration ISRCTN14990068
Subject(s)
COVID-19 , Dyspnea , Intellectual DisabilityABSTRACT
Digital proximity tracing (DPT) apps have been released to mitigate SARS-CoV-2 transmission, but it remains unclear how their effectiveness should be monitored. The aim of this study was to formalize indicators for measuring the fulfillment of assumptions for appropriate proximity tracing app functioning. Six indicators were developed to monitor the SwissCovid app functioning and effectiveness in the Swiss population. Using official statistics and survey data, we calculated indicator values and examined socio-demographic factors associated with the SwissCovid app utilization. Indicators show that 1 in 3 adults in Switzerland have downloaded the app. However, only 15% of new cases also triggered DPT-app notifications, and indicators also reveal ignored app notifications. In the full survey sample (n=2098), higher monthly household income or being a non-smoker were associated with higher SwissCovid app uptake; older age or having a non-Swiss nationality with a lower uptake. In a subsample including more detailed information (n=701), high trust in health authorities was associated with higher SwissCovid app uptake. The indicators help to monitor key drivers of DPT-apps effectiveness and hint to non-compliance issues. Streamlining procedures, removing technical hurdles, and communicating the usefulness of DPT-apps are crucial to promote uptake, compliance, and ultimately effectiveness of DPT-apps for pandemic mitigation.