Living conditions, seroprevalence and symptoms of COVID-19 in slums in the Metropolitan Region of Vitória (Espírito Santo)

Abstract

Objectives: to estimate the prevalence of SARS-CoV-2 infection in residents of the Greater Vitória region living in subnormal and non-subnormal agglomerates, and to compare sociodemographic and clinical characteristics of total residents (infected and not infected with SARS-CoV-2) between them. Methods: Population-based prevalence study conducted by serological testing in 2020, with a study unit in households in Greater Vitória, grouped into census tracts classified as sub-normal agglomerates and non-sub-normal agglomerates. The two groups were compared in terms of prevalence and associated factors. The significance level adopted was 5%. Results: The prevalence found in the sub-normal clusters was 12.05% (95%CI 9.59–14.50), and in the non-sub-normal clusters 10.23% (95%CI 7.97–12.50) this difference was not statistically significant (p = 0.273). Comparing the sociodemographic characteristics, more people who declare themselves to be of mixed race were found in the sub-normal clusters, a higher percentage of illiterates and people with only elementary education, greater number of residents per household, longer stay in public transportation, sharing a bathroom with another household, fewer bedrooms per residence and higher frequency of irregular water supply when compared to non-sub-normal clusters (p < 0.05). Conclusions: The epidemiological characteristics of sub-normal clusters’ residents show the social inequalities that can hinder control measures in a pandemic situation.

Prevalence and predictors of anti-SARS-CoV-2 serology in a highly vulnerable population of Rio de Janeiro: A population-based serosurvey

“… 71 Whereas in Vitória city among those with reactive serology, 45%, 40% and 38% reported anosmia, cough, and myalgia, respectively. 38 These differences may be attributed to a shorter period of symptoms observation in our study compared to the first-mentioned study (past two weeks versus past two-to-three months), but not different from the second study. Another potential reason could be related to the performance of serological assays used.…”

“… 37 Our estimates are closer to those found in studies including people living in vulnerable areas of other cities in Brazil. In the metropolitan area of Vitória (also in the Southeast region of Brazil), in June 2020, the estimated prevalence among individuals aged two years or older living in slums was 12·1% ( n= 714) 38 ; while a study that included 2,035 urban slum residents Salvador city (Northeast region of Brazil) observed a 46·4% prevalence (from November 2020 to February 2021). 39 Additionally, a survey conducted with homeless persons in a large day-shelter in São Paulo city (Southeast region of Brazil) found a 54·7% prevalence in August 2020.…”

“…Another potential reason could be related to the performance of serological assays used. We used a CLIA quantitative anti-S IgG assay while other studies used lateral flow IgM/IgG anti-S rapid tests (Wondfo test, Wondfo Biotech Co., Guangzhou, China 71 and IgM/IgG test from Celer Technologies Inc. 38 ). Lateral flow serological tests have lower sensitivity than chemiluminescence immune assays and ELISA assays.…”