Medical Experts Dispel Polio Resurgence Fears In Kolkata

Fears that the dreaded polio virus has resurfaced after being eradicated eight years ago were dispelled by medical experts who examined the virus found in the sewage in Kolkata and found it inactive.

According to health ministry sources, vaccine-derived polio virus was detected in the environmental surveillance of sewage and not wild polio virus.

The National Institute of Virology Mumbai did the genetic sequencing, the sources said.

It can occur in any country where Oral Polio vaccine is given.

A senior official of the West Bengal Health department said the virus found in the sewage of Borough No 15 in the city's Metiabruz area is Vaccine derived Polio virus and is not threatening.

There is nothing to worry since it is not a Wild polio virus, the health official said.

A Vaccine derived Polio virus is not capable of infecting anyone unlike a Wild polio virus.

Poliomyelitis (polio) is a highly infectious viral disease that largely affects children under five years of age. The virus is transmitted by person-to-person spread mainly through the faecal-oral route or, less frequently, by a common vehicle (e.g. contaminated water or food) and multiplies in the intestine, from where it can invade the nervous system and cause paralysis.

"We have asked all the hospitals and medical colleges to conduct necessary surveillance programmes in their respective areas as a part of our preventive measures," West Bengal Director of Health Services (DHS) Dr Siddhartha Niyogi told PTI.

Surveillance is carried out in various places, such as common toilets and drains of congested areas to detect possible traces of the polio virus.

"Finding the virus in the city sewage could be due to two reasons--the virus may have been been excreted by a polio-infected child or a child who had received the live polio vaccine. Due to open defecation by the child, the virus was found in the sewage," Dr Niyogi explained.

"It is not unusual to find a vaccine virus, it's quite natural. So there is nothing to worry . Surveillance is an ongoing process and will continue for the time being. Other than the regular surveillance in the hospitals, we have directed a special surveillance on children with low immunity," the DHS said.

Frequent outbreak of measles and detection of VDPV Type 1 virus from a sewage sample at Metiabruz Borough 15 indicates the necessity of surveillance, Dr Niyogi said.

Last time such VDPV was detected in New Delhi in 2018, health ministry sources said.

The last polio case was reported from West Bengal's Howrah district in 2011 when a two-year-old girl was found to have contracted the disease.

On March 26, 2014, the World Health Organization (WHO) had certified India as a polio-free country.