RESUMO
The possible faecal-oral transmission of SARS-CoV-2 through domestic discharges has emerged as a serious public health concern. Based on persistence of the virus in environment, the wastewater-based epidemiology (WBE) enabled the surveillance of infection in a community. The water bodies connected to the anthropogenic activities have strong possibility of presence of the SARS-CoV-2 genetic material. In this work, we monitored urban, peri-urban and rural lakes in and around Hyderabad as a long-term surveillance study for presence of enteric virus SARS-CoV-2 gene fragments. The study time of seven months coincided with the first and second wave of COVID-19 infection. The study depicted differential viral RNA copies in the urban lake with high viral load observed during the peaks of wave I and wave II. Distinct variability in viral genes detection was observed amongst all five lakes which were in concordance with the human activity of the catchment area. The SARS-CoV-2 genes were not detected in peri-urban and rural lakes, whereas the urban lakes having direct functional attributes from domestic activity, in the community showed presence of viral load. The outcome of the study clearly shows that the urban water streams linked with domestic discharge will function as a proxy for wastewater epidemiological studies. The surge in viral gene load from February 2021 sample suggests the on shoot of the second wave of infection, which correlated well with the prevailing pandemic situation. Implementation of regular WBE based monitoring system for the water bodies/wastewater in the urban and semi-urban areas will help to understand the outbreak and spread of virus in the community.
RESUMO
Wastewater-based epidemiology (WBE) of SARS-CoV-2 emerged as an advantageous method to study the infection dynamics at substantial population level. A temporal glimpse at sewage viral genome helps as diagnostic tool to understand the viral spread at community level. In this study, for the long-term epidemiological surveillance, we monitored the SARS-CoV-2 genetic material in domestic sewage by adopting the longitudinal sampling to represent a selected community ([~]1.8 lakhs population which occupies 1.79% of the total population of Hyderabad city) to understand the dynamics of infection. Dynamics and spread of COVID-19 outbreak within the selected community were achieved by studying the longitudinal sampling for a specific period of time. WBE also promotes clinical scrutiny along with disease detection and management, in contrast to an advance warning signal to anticipate outbreaks.
RESUMO
Post COVID-19 outbreak, wastewater-based epidemiology (WBE) studies as surveillance system is becoming an emerging interest due to its functional advantage as tool for early warning signal and to catalyze effective disease management strategies based on the community diagnosis. A comprehensive attempt was made in this study to define a methodological approach for conducting WBE studies in the framework of identifying/selection of surveillance sites, standardizing sampling policy, designing sampling protocols to improve sensitivity, adopting safety protocol, and interpreting the data. The methodology was applied to a community and studied its epidemiological status with reference to occurrence, persistence, and variation of SARS-CoV-2 genome load in wastewater system to understand the prevalence of infection. Hourly and daily grab samples were analyzed and compared with the composite samples over a surveillance window of 7 days. Based on the SARS-CoV-2 RNA copies/L, faeces shedding, and volume of sewage generated the infected individuals and the population who are in active phase in the studied community was estimated.
