Reaching the unreached: how a measles campaign uncovered zero-dose children in Bangladesh

^{WHO SIMO is conducting a household-level assessment at a bamboo shelter, reviewing health status and vaccination history with the family. Kotalipara Upazila, Gopalganj, 28 April 2026.}

The challenges they faced came to light during Bangladesh’s nationwide emergency measles-rubella vaccination campaign, launched in April 2026 in response to rising measles transmission and widening immunity gaps among children aged 6–59 months. 

In Gopalganj District, a Rapid Convenience Monitoring visit conducted following a campaign session in Ghagar Union on 27 April identified at least 16 eligible children from “floating” families who had missed the campaign entirely. The visit was carried out by Dr Nishat Tasnim, WHO’s Surveillance and Immunization Medical Officer (SIMO) together with the government’s first-line supervisor. 
It was found that Abu Bakkar had missed all routine vaccines scheduled during infancy and early childhood, while Karimon was overdue for nearly all vaccines recommended during her first year of life.

“I did not know about vaccines or that my children needed them,” said their mother, Rahima. “When the doctor came to our shelter and explained, I understood their importance.” The missed doses were not about parental refusal, but the persistent challenge of reaching mobile and hard-to-reach populations. Although Bangladesh’s Expanded Programme on Immunization (EPI) microplanning framework identifies high-risk and underserved groups, translating those plans into consistent field implementation remains difficult.

Mobile families are often absent from fixed household registers, while outreach services struggle to keep pace with constantly shifting settlements. “This is why campaigns like this are so critical,” says Dr Nishat. “Too often, these camps – and supplementary activities like them – are the only opportunity these communities have to meet health workers where they are, and as they live.”  

Following the identification of the missed children, district health authorities were immediately informed, enabling rapid action. On 29 April, a dedicated vaccination session and community dialogue were organized for the missed families. Health workers met with parents, explained the importance of immunization and encouraged every eligible child to avail protection. District authorities also instructed local health teams across Gopalganj to identify other nomadic and floating communities and take corrective action where needed.

For Abu Bakkar and Karimon, the follow-up session marked a turning point. For the first time, their names entered the local health system. Both children received measles vaccines during the special session, while district EPI teams began planning catch-up immunization for zero-dose children identified during the campaign. “We reached 16 missed children in Ghagar Union — but this is just the beginning. Our goal now is to ensure no floating or nomadic community is left behind in the future.” Dr Abu Sayed Mohammad Faruk, Civil Surgeon, Gopalganj.

The experience in Ghagar Union highlights how children from mobile and underserved communities can remain invisible to immunization systems, even during nationwide campaigns. In Gopalganj, rapid follow-up action helped identify and vaccinate children who might otherwise have remained unreached. With continued government leadership and WHO support, efforts to reach zero-dose and under-immunized children can be strengthened further – helping ensure that every child, regardless of where they live or how often they move, receives lifesaving vaccines.