Determinação do padrão espaço-temporal de propagação da covid-19 com base no monitoramento do sars-cov-2 no esgoto de Belo Horizonte

Abstract

The world has faced important challenges due to the Covid-19 pandemic caused by the SARS-CoV-2 virus, such as inadequate clinical tests for the diagnosis of the disease and the existence of asymptomatic infected individuals, which make it difficult to determine the actual number of infected people. In this context, the monitoring of SARS-CoV-2 in sanitary sewage systems can be a methodology capable of providing robustness to epidemiological and environmental surveillance systems. The present research aimed to better understand the circulation of the SARS-CoV-2 virus in Belo Horizonte, based on the monitoring of its SARS-CoV-2 concentrations and loads in the local sanitary sewage system. Given the rapid and widespread spread of COVID-19 in Brazil, associated with the utterly inadequate clinical testing of its population, the proposed study contributes to the understanding of the circulation of SARSCoV-2 in Brazilian metropolitan regions by using indirect estimation methods that consider at the same time the spatial and temporal patterns of contagion. This research uses secondary data from the Municipal Health Department of Belo Horizonte, Copasa, the pilot project: “Detection and quantification of the new coronavirus in sewage samples in the city of Belo Horizonte”, and the Project Brazilian Network for Covid Monitoring in Sewage. This project is extremely relevant because the monitoring of sewage included not only the entry and exit of treatment plants (WWTPs), but also included monitoring of sewage in a regionalized manner, at representative points of different social strata of the population. This is an appropriate strategy for countries such as Brazil, since monitoring sewage only in ETEs is not enough to identify the magnitude of virus circulation in a large metropolis, such as Belo Horizonte. Furthermore, it is very important to monitor the sewage generated by the part of the population that lives in more vulnerable areas, whose sewage, for the most part, does not reach the ETEs, either due to the absence of collection networks or the lack of interconnection of collection networks. to the ETEs. Thus, the use of weekly viral concentration data makes it possible to understand, measure and compare the spatio-temporal pattern of the distribution of the spread of infections in the different sub-basins of Belo Horizonte - essential information for managers to decide on localized intervention of nonpharmacological measures. of confrontation. By studying how the disease spread in the study area, using tools such as the Hoover Location Index, the Relative Prevalence Index and spatio-temporal analyses, this work contributes with information for the adoption of better strategies to face similar pandemics, as well in the generation of analytical tools that facilitate the confrontation of future similar problems.