Mumbai: The state government is starting a special drive to immunize around 1,200 children from four wards with oral and injectable polio vaccines today. The move follows the detection of type-2 vaccine-virus strain of polio in a sewage sample from Kurla, said a report in The Times of India. The drive is aimed at those kids between 0-2 years of age who missed their routine doses. Following the discovery of the p2 vaccine-virus during surveillance of sewage samples in August-end, a screening drive was started in Kurla, Mankhurd, Deonar and Andheri east, Vikhroli and Bhandup. (Also read: Contaminated Vaccine Given to Kids in Maharashtra, UP, Telangana) Also Read - Vaccination Drive Suspended in Maharashtra Till Monday Due to CoWin App Glitches

A child in that age group should get five doses of oral polio vaccine (OPV) and two doses of inactivated polio vaccine (IPV) injection for protection against all three strains. Health workers found that around 1,200 children had missed out on some doses. “Targeted mop-ups are intensified immunization campaigns carried out in areas where the virus is last recorded. Even though the p2 sample we found was of vaccine-virus and not of wild polio, it’s important that children are 100% protected,” said a civic official. Also Read - Maharashtra Man Kills Girlfriend to Avoid Marrying Her, Hides Body in Walls of Flat

Vaccine-virus is added to the vaccine to generate immunity. The report said it was still a mystery how the p2 vaccine-virus appeared in the city’s sewage. More so, after the state’s public health minister had said that batches of vaccine suspected to be contaminated with the strain never reached Maharashtra. A member of the city’s surveillance team told the daily, “We didn’t find a single vial of the old trivalent vaccine that contained the p2 strain anywhere in the city. So the question lingers where it came from,” he said, adding no other environmental samples came positive after the one in August. Also Read - World's Biggest Vaccination Drive to be Launched Today, Farmers-Centre Talks Reach no Conclusion: Check Top Headlines at This Hour

A state official said if the children have missed out on other vaccines covered under Mission Indradhanush such as tetanus, measles, meningitis and pneumonia, those will also be administered.