US researchers have identified at least four cryptic variants of SARS-CoV-2 in wastewater samples collected from New York City′s public sewer system.

According to Marc Johnson, professor of molecular microbiology and immunology at the University of Missouri, and study co-corresponding author, the cryptic mutations could be tied to possible animal origins. Although the origins have not been confirmed yet, a possible source could be rats.

The investigators have sampled wastewater from 14 treatment plants in New York City since June 2020. They have also talked to other researchers in the US who have been doing similar work and have seen some unusual results.

Johnson said that while they were different, all of them seemed to have similar mutations in common at one particular location, i.e, Q498. In most of the samples from New York City, the Q had turned into a Y (glutamine had turned into tyrosine). According to the database, there seems to be no human patient who has had that mutation, he said.

The findings from the research are published in Nature Communications… (TWC – IANS, February 7, 2022)