Why in news?
Sampling sewage for viral particles is a time-tested method of environment surveillance and is routinely resorted to for understanding circulation of several viruses — wild and vaccine-derived polio, rota virus, Hepatitis E and typhoid — in the community.
Now, researchers in France have found that sewage surveillance can help in understanding the circulation of novel coronavirus (SARS-CoV-2) in the human population.
Why would this work?
- People infected with the virus have been found to shed the virus in their stools. And by studying sewage samples, it is possible to know the viral load in the community through modelling once data on how many viral particles are shed by individuals and how the viral particles get diluted in sewage are available.
- In the case of novel coronavirus (COVID-19), sewage surveillance becomes particularly useful as a large percentage of infected population is either asymptomatic or show only mild symptoms.
- Hence, there is a greatly likelihood that circulation of the virus in the community will be detected quite late, if at all.
- The other benefit is that sewage surveillance can be carried out independent of testing in humans and will be able to pick up early signs even when people in the community do not show symptoms.
- The ability of sewage surveillance to decipher community spread even when people are asymptomatic is akin to antibody testing.