title: Author's reply.
authors.affiliation: National Polio Surveillance Project, Gate No. 31, 2nd Floor Jawaharlal Nehru Stadium, 110003, New Delhi.
authors.forename: Jay D
authors.initials: JD
authors.lastname: Wenger
authors.affiliation: National Polio Surveillance Project, Gate No. 31, 2nd Floor Jawaharlal Nehru Stadium, 110003, New Delhi.
authors.forename: Dhananjay
authors.initials: D
authors.lastname: Gupta