Journal Article

Population infection estimation from wastewater surveillance for SARS-CoV-2 in Nagpur, India during the second pandemic wave

Crooks, Colin, Bhatnagar, Tarun, Gomes, Rachel L., McClure, Patrick, Tarr, Alexander W., Nag, Aditi, Nayak, Amit R., Dudani, Hemanshi, Singer, Andrew, Lade, Ranjana, Husain, Aliabbas A., Monaghan, Tanya M., Shrivastava, Sandeep K., Kumar, Saravana, Kashyap, Rajpal Singh, Meena, Ekta, Acheampong, Edward, Arora, Sudipti

2024

Overview

Wastewater-based epidemiology (WBE) has emerged as an effective environmental surveillance tool for predicting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease outbreaks in high-income countries (HICs) with centralized sewage infrastructure. However, few studies have applied WBE alongside epidemic disease modelling to estimate the prevalence of SARS-CoV-2 in low-resource settings. This study aimed to explore the feasibility of collecting untreated wastewater samples from rural and urban catchment areas of Nagpur district, to detect and quantify SARS-CoV-2 using real-time qPCR, to compare geographic differences in viral loads, and to integrate the wastewater data into a modified Susceptible-Exposed-Infectious-Confirmed Positives-Recovered (SEIPR) model. Of the 983 wastewater samples analyzed for SARS-CoV-2 RNA, we detected significantly higher sample positivity rates, 43.7% (95% confidence interval (CI) 40.1, 47.4) and 30.4% (95% CI 24.66, 36.66), and higher viral loads for the urban compared with rural samples, respectively. The Basic reproductive number, R 0 , positively correlated with population density and negatively correlated with humidity, a proxy for rainfall and dilution of waste in the sewers. The SEIPR model estimated the rate of unreported coronavirus disease 2019 (COVID-19) cases at the start of the wave as 13.97 [95% CI (10.17, 17.0)] times that of confirmed cases, representing a material difference in cases and healthcare resource burden. Wastewater surveillance might prove to be a more reliable way to prepare for surges in COVID-19 cases during future waves for authorities.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Accuracy / Biology and life sciences / Catchment areas / Confidence intervals / Coronaviruses / COVID-19 / COVID-19 - diagnosis / COVID-19 - epidemiology / COVID-19 - virology / Dilution / Disease transmission / Earth Sciences / Epidemiology / Estimates / Health aspects / Health surveillance / Humans / Humidity / India - epidemiology / Infections / Infrastructure (Economics) / Mathematical models / Medical research / Medicine and health sciences / Medicine, Experimental / Monte Carlo simulation / Ordinary differential equations / Pandemics / People and Places / Physical sciences / Population / Population density / Prevalence studies (Epidemiology) / Public health / Rain and rainfall / Rainfall / Real time / Research and analysis methods / Respiratory diseases / RNA / Rural areas / Sanitation / SARS-CoV-2 - isolation & purification / Severe acute respiratory syndrome coronavirus 2 / Sewage / Sewage - virology / Sewer systems / Sewers / Surveillance / Urban catchments / Viral diseases / Viral Load / Wastewater / Wastewater - virology / Wastewater-Based Epidemiological Monitoring / Water sampling / Water treatment