Strengthen immunisation capacities, focus on unvaccinated children: WHO to Southeast Asian countries

The World Health Organisation (WHO) on Monday called for focused efforts to provide life-saving vaccines to nearly 4.6 million unvaccinated children in Southeast Asia as countries intensify efforts to equal or surpass pre-Covid vaccination coverage levels.

The number of unvaccinated or zero dose children more than doubled from 2 million in 2019 to 4.6 million in the region by 2021 despite efforts by countries to maintain or restore routine childhood immunisation, said Poonam Khetrapal Singh, Regional Director, WHO, South-East Asia.

"We need to urgently address gaps and challenges aggravated by the COVID-19 pandemic," Singh said.

She was addressing representatives of health ministries, national immunisation advisory groups and partner agencies participating in a four-day regional workshop to strengthen routine immunisation capacities post-Covid.

"We need to accurately identify high-risk areas with high numbers of zero-dose children, and rapidly improve access and uptake of routine immunisation," Singh said.

The catch-up immunisation activities and special campaigns being rolled out by countries must be reviewed and measures like increasing the age limit of target populations adopted where needed for filling the immunity gaps, she said.

The behavioural and social drivers of immunisation should be identified to guide focused interventions and strategies to engage communities to accelerate the demand for vaccination, she added.

The regional director emphasised the need for periodic mapping of at-risk populations and for developing actionable plans to address gaps in immunisation.

Noting that routine immunisation coverage in the region has been highly variable, she said several countries have maintained high childhood vaccination coverage even during the COVID-19 pandemic and are now accelerating progress.

Some others where coverage declined in 2020 but stabilised in 2021 and 2022 can now reach pre-pandemic levels. However, there are also countries where coverage continues to be sub-optimal.

Singh commended Timor-Leste for introducing the pneumococcal vaccine in the catch-up campaigns and Nepal for becoming the fourth country globally to introduce the typhoid conjugate vaccine in 2022.

She also complimented Bangladesh for restoring immunisation services to pre-Covid levels by June 2020; India for launching an intensified vaccination drive, Mission Indradhanush; and Indonesia for completing the readiness requirements for use of the novel oral polio vaccine type 2 within a record time of two weeks from the notification of type 2 circulating vaccine-derived polio outbreak in November 2022.

The WHO South-East Asia region continues to be free of wild poliovirus and sustains its maternal and neonatal tetanus elimination status, she added.

With persistent effort over the years, routine immunisation coverage in the region had crossed 90 per cent in 2019. The number of zero dose children declined from over 5 million in 2010 to 2 million in 2019, according to Singh.

However, during the COVID-19 pandemic, the coverage of DPT3 (third dose of vaccine to protect against diphtheria, pertussis and tetanus), which is the standard indicator to measure vaccination coverage, declined from 91 per cent in 2019 to 85 per cent in 2020 and fell further to 82 per cent in 2021, sharply increasing the number of unvaccinated and under-vaccinated children in a region which has the biggest birth cohort, Singh said.