India tracks polio virus in sewage

From Express India:

LUCKNOW, India -- Following success of sewage surveillance for wild polio virus in Mumbai, the Centre is now planning to go ahead with a similar surveillance in Delhi.

The surveillance was introduced through the Indian Council for Medical Research (ICMR) in Mumbai in 2001 and since then, the city has been able to keep track of the wild virus, even though no human cases have been reported. In Mumbai, Enterovirus Research Centre of the ICMR collects the sample from municipal sewage water in the high-risk areas.

Experts say Delhi is similar to Mumbai in terms of high-level migration of labourers from the polio-affected regions of Uttar Pradesh and Bihar.

Polio spreads through faecal-oral route and can be found in faecal particles present in sewage water, so even when no human cases are reported, sampling from environment can alert the health authorities.

Dr Devendra Khandait, National Surveillance team leader with National Polio Surveillance Programme told The Indian Express: “The surveillance will help identify the wild virus in the environment even when there are no human cases and adequate precautions can be taken to prevent its spread.”

Sources say the Centre floated the idea around two months ago and work is on to decide the modalities after discussions with experts associated with the polio eradication.

Officials at the Union Ministry of Health said the work has been left to the National Polio Surveillance Project (NPSP) officials and is at initial stages. The NPSP is a Central government and WHO collaboration for polio surveillance and its partners are UNICEF, Rotary etc.

As to why such surveillance has not been initiated in endemic areas of UP and Bihar, experts say there is no need for additional surveillance at present because the circulation of virus is known though human cases.

So far, Delhi has reported three cases of the more virulent Type 1 polio virus and one case of Type-3 polio virus this year. The first case had shown clear history of migration from Uttar Pradesh.