The presence of polio virus (P2 strain) in the sewerage samples collected from the Secunderabad railway station has created a scare among the common people in the city. Earlier, the healthcare surveillance authorities had collected a total of 14 sewage samples between January 2015 and May 2016, from different parts of the country tested positive for vaccine derived polio virus (VDPV).
Responding to this, the healthcare department and the authorities conducted immediate drives to check if any of the residents of Hyderabad and Ranga Reddy are infected with the virus. However, the authorities have found that the samples collected from sewerage though have tested positive; there is no case of any infection so far. “The detected polio virus strain is VDPV in a sewage sample collected near the Secunderabad railway station. No children have been found to be affected by the detected VDPV,” informed a health department source.
India has been declared polio free by World Health Organisation since past 5 years and the country continues to be polio free. The last case was seen on 13th January, 2011 and it is more than 5 years that no wild polio virus has been detected.
However with this latest outcome, healthcare authorities in Hyderabad conducted a rapid surveillance review of the area. That has revealed that the immunity against polio type 2 is high as trivalent oral polio vaccine (tOPV) which was in use in the state until 24th April, 2016 and two mass vaccination campaigns were conducted in January and February, 2016. As per recent sample survey in the area, 94 per cent children were found to have received at least 3 doses of OPV. Therefore, chances of its transmission in concerned area are unlikely.
However, as a precautionary measure against polio, a special immunization drive is being held, covering high-risk areas of Hyderabad and Rangareddy districts, starting from 20th June, where an estimated 300,000 children will be protected against polio using inactivated polio vaccine (IPV). The special immunization campaign will ensure all vulnerable children living in high-risk areas are given protection against polio.
As part of the special campaign being organised, children between the age group of six weeks to three years will be given an additional dose of the injectable polio vaccine (IPV). Vaccination booths will be set up in the areas being covered in these campaigns.
India continues to maintain a highly sensitive surveillance system for polio. All cases of paralysis with sudden onset in children up to 15 years (which is called Acute Flaccid Paralysis or AFP) are picked up by the polio surveillance network. Each of these cases is followed up and their stool samples tested for polio virus in WHO accredited laboratories. In addition, sewage samples are collected from over 30 sites spread across the country for polio virus detection at regular intervals.