Incidence of SARS-CoV-2 over four epidemic waves in a low-resource community in Rio de Janeiro, Brazil: A prospective cohort study

The Lancet Regional Health. Americas

Trevon Fuller¹  Patricia Brasil¹  Guilherme Calvet¹  Luana Damasceno¹  Chris Smith²  Jimmy Whitworth²  Paola Cristina Resende³  Marilda Siqueira³  Leonardo Soares Bastos⁴  Owaldo Gonçalves Cruz⁴  Marilia Sa Carvalho⁴ 

[1] Acute Febrile Illnesses Laboratory, Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Av. Brasil, 4365 - Manguinhos, Rio de Janeiro, RJ 21040-900, Brazil;Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, United Kingdom;Laboratory of Respiratory Viruses and Measles, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Brazil;Scientific Computation Program, Oswaldo Cruz Foundation, Rio de Janeiro, RJ, Brazil;

关键词: Incidence density;    COVID-19;    Household transmission;   

DOI  :  

来源: DOAJ

【 摘 要 】

Summary:Background: Incidence rates of SARS-CoV-2 infections in low-resource communities can inform vaccination strategies and non-pharmaceutical interventions (NPIs). Our objective was to estimate incidence over four epidemic waves in a slum in Rio de Janeiro, a proxy for economically deprived areas in the Global South. Methods: Prospective cohort of children and household contacts screened for SARS-CoV-2 by PCR and serology (IgG). The incidence density of PCR positive infections estimated for each wave - the first wave, Zeta, Gamma and Delta - was compared to an index combining NPIs and vaccination coverage. Findings: 718 families and 2501 individuals were enrolled, from May 2020 to November 2021. The incidence density of SARS-CoV-2 infection due to the first wave was 2, 3 times that of the other waves. The incidence among children was lower than that of older participants, except in later waves, when vaccination of the elderly reached 90%. Household agglomeration was significantly associated with incidence only during the first wave. Interpretation: The incidence of infection greatly exceeded rates reported in similar cohorts. The observed reduction in incidence in the elderly during the Delta variant wave, in spite of the rollback of NPIs, can be attributed to increased vaccine coverage. The high incidence in young people reinforces the importance of vaccination in this age group, a policy that has yet to receive the full support of some sectors of society. Funding: UK Medical Research Council, Foundation for the Advancement of Science of the State of Rio de Janeiro, National Council for Scientific and Technological Development.

【 授权许可】

Unknown