Using RT-PCR Testing to Assess the Effectiveness of Outbreak Control Efforts in São Paulo State, the Pandemic’s Epicenter in Brazil, according to Socioeconomic Vulnerabilities

Abstract

AbstractBackgroundThe testing of infected persons with SARS-CoV-2 is one of the cornerstones of an effective strategy deployed for pandemic control. The public health diagnostic effort is particularly important in regions with a critical transmission scenario and in vulnerable populations in these districts, such as São Paulo state, the Brazilian epicenter of the COVID-19 pandemic.MethodsWe developed an RT-PCR testing intensity effort index (RT-PCR TIEI) composed of seven indicators to assess the survelliance efforts in the São Paulo State. We used dynamic time-series cross-sectional models to analyze the association between the RT-PCR TIEI, the population living under high socioeconomic vulnerability levels, dependent on public health service (SUS), per capita income, and population density.ResultsOn average, the RT-PCR TIEI score was 21.07. In the long-run, the RT-PCR TIEI is negatively associated with socioeconomic vulnerability (p-value=0.000, 95% CI −0.887, - 0.811), with a higher proportion of the population dependent on SUS (p-value= 0.000, 95% CI −0.871, −0.805), per capita income (p-value= 0.000, 95% CI −0.849,-0.792) and with population density (p-value=0.000, 95% CI −0.853; −0.801).ConclusionTesting efforts declined as the pandemic advanced, and the the lowest RT-PCR TIEI values were found in the most socioeconomic vulnerable RHDs. Local public laboratory presence was a predictor of a higher score. Thus, the low testing RT-PCR efforts and local laboratory inequalities affected surveillance capability, especially for socioeconomic vulnerable populations.