On 14 June, an active strain of a wild polio virus (P2 strain) was detected in a water sample that was collected from a drain, triggering a "global emergency" that was sounded by the Telengana government. As a preventive measure, two lakh vaccines were airlifted from Geneva to immunise more than three lakh children in the Hyderabad and Ranga district.
During a routine surveillance where 30 samples were collected from various parts of Hyderabad, the polio strain was detected in a sewerage sample that was derived from the Amberpet sewerage treatment plant on 17 May.
It has been over five years since the Derived Polio Virus (VDPV) strain was last detected in the country. "The government has decided to conduct a special campaign against polio in Hyderabad and parts of Ranga Reddy from 20 June to 26 June," Rajeshwar Tiwari, prinicipal secretary of health, was quoted to have said in a Times of Indiareport. He added that this wasn't the first time the strain was traced. The wild polio strain was earlier detected in Bihar, Gujarat, UP and even Delhi.
The oral polio vaccine that was earlier administered contained P1, P2 and P3 strains, but as the P2 strain had not surfaced in a long time, the latest versions of the vaccines did not contain the P2 strain.
"In this case, the P2 strain is vaccine derived. Someone vaccinated 10 months to a year ago released the strain through stool. Such rare cases happen when a child's immunity is very low. To avoid such stray cases, that happens one in a million, the P2 strain is no longer given even in vaccines," Dr G Srinivasa Rao, chief programme officer, National Health Mission, Telangana, was quoted as saying.
"We'll be following WHO-set standards during our programmes," he added.
Even though no case of polio has been reported as of now, a vaccination programme of massive proportions is going to be launched in the state as a preventive measure. In a bid to control the spread of the P2 strain, a special campaign is to be launched, where children between six weeks to three years will be given additional doses of the injectable polio vaccine (IPV). Booths will be set up in areas being covered in these campaigns.
While door-to-door vaccination facilities will not be made available, state officials said monitoring teams will be deployed in all areas where the campaign is to be launched. Parents of children living in these areas will be encouraged to ensure that their children get the IPV dose from the vaccine booth, which will provide additional protection against all types of polio.