Socioeconomic Vulnerabilities and the Intensity of RT-PCR SARS-CoV-2 Testing Efforts in the Public Health System in Sao Paulo State

BackgroundThe 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 Sao 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 Sao 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.