Rapid assessment of pulse polio campaign shows high vaccine coverage, highlights gaps in Chennai

Polio drops being administered to a child near Mogappair West Bus Stand in Chennai. File photo
| Photo Credit: M. VEDHAN

Compared to the rest of Tamil Nadu, Chennai saw a higher number of children aged below five non-vaccinated during the Intensified Pulse Polio Immunisation (IPPI) campaign in early 2024 that registered an overall high Oral Polio Vaccine (OPV) coverage. The city accounted for nearly 21% of the non-vaccinated children, highlighting the gaps in an urban area and the need for targeted community outreach, a rapid assessment by the Directorate of Public Health (DPH) and Preventive Medicine has found.

On March 3, 2024, the IPPI campaign was conducted in Tamil Nadu, covering 59.20 lakh children aged zero to five. The State’s polio dipstick survey, which offers a rapid and efficient means of detecting coverage after each yearly IPPI campaign, was conducted telephonically on two dates — March 5 and March 13 (third and 10th day of IPPI). It was done to understand the vaccine coverage and reasons for receiving/non-receiving the Oral Polio Vaccine during IPPI, according to an article published in the Tamil Nadu Journal of Public Health and Medical Research — Telephonic survey to assess vaccination coverage in IPPI campaign 2024, Tamil Nadu: A rapid assessment.

The authors used systematic random sampling from the Pregnancy and Infant Cohort Monitoring and Evaluation portal. A sample of 1,200 mothers across 46 Health Unit Districts (25 mothers from each HUD and 75 from Chennai Corporation) were targeted.

Of the total 2,235 calls made to the mothers, 1,174 (52.5%) responded. Of them, 1,073 (91.3%) reported that their children received OPV from March 3 to March 9 during the campaign. ICDS-Anganwadi centres (59%) were the most common place where the children received the drops, followed by health facilities and schools, the survey found.

Of the 101 (8.6%) unvaccinated, 21% were from Chennai, followed by Paramakudi, Kanniyakumari, Thanjavur, Tirupathur districts — all in single digits. Child’s sickness (30%), being out of State (29%), and not being aware of the place and date of the campaign (23%) were the primary reasons quoted for not receiving the OPV during the IPPI campaign. These reasons, the surveyors observed, indicated that more tailored outreach efforts, including communication about the vaccination schedule and alternative provisions for absentee children, could enhance the coverage.

The survey affirmed the role of ICDS-Anganwadi centres as key vaccination hubs, and stressed the importance of addressing coverage disparities, especially in regions such as Chennai that had a higher rate of non-vaccination, they said.

Challenges in urban areas

T.S. Selvavinayagam, Director of Public Health, said there are a number of challenges in urban areas. “In an urban area, we have high-rise buildings where healthcare personnel do not get access and habitations where people may not know or be aware of immunisation campaigns. We need to address such challenges,” he said.

The children who were not vaccinated on the third day of IPPI were followed up, after which 47 were vaccinated during mop-up days. This led to a cumulative OPV coverage of 95.4% at the end of the campaign, the survey said.