OBJECTIVE:

To monitor the occurrence of SARS-CoV-2 RNA in surface waters of urban canals in the city of Belém, state of Pará, between 2021 and 2022, correlating the findings with environmental parameters, microbiological indicators, and epidemiological data.

MATERIALS AND METHODS:

Twenty-four monthly sampling campaigns were conducted at eight sites, totaling 192 samples. The samples were analyzed for physicochemical parameters using a multiparameter probe, the presence of thermotolerant coliforms (TTC) and Escherichia coli by the ONPG-MUG method, and viral detection by RT-qPCR targeting the N and ORF1ab genes.

RESULTS:

All samples showed TTC and E. coli concentrations above the limits established by CONAMA Resolution No. 274/2000. SARS-CoV-2 RNA was detected in 23.44% of samples for the N gene and 11.45% for the ORF1ab gene, with higher detection rates in the early months of the year, coinciding with peaks in COVID-19 cases. The ORF1ab gene showed a significant correlation with cases and deaths (rs = 0.73595; p = 0.0064 and rs = 0.78101; p = 0.0027 in 2021) and accounted for 81.69% of the variation in case numbers (R2 = 0.8169). Temperature was the only environmental variable significantly correlated with the N gene, while no associations were observed with microbiological indicators.

CONCLUSION:

The detection of SARS-CoV-2 in surface waters of Belém highlights public health risks, particularly in areas with inadequate sanitation, reinforcing the role of environmental virology as a strategic tool for epidemiological surveillance and for informing policies aimed at risk prevention and mitigation.