Polioviruses can take several forms and wild polioviruses are the most commonly known. Yet, there is another form of polio: circulating vaccine-derived poliovirus, or cVDPV. While this form is rare in a past, it has been on the rise in recent years due to low vaccination rates in communities.[1] The Global Polio Eradication Initiative registered worldwide 1067 cases of cVDPV in 2020[2] and one of these cases was reported from Malaysia as well as 3 cases in 2019.

The virus was detected in December 2019, in two areas: the state of Sabah and the Federal Territory of Labuan. Located close to international borders, these areas host a high number of immigrant and stateless people. It is estimated that in Sabah non-citizens make up 28% of the population, while in Malaysia as a whole, the number amounts to 3 million.[3] This poses a challenge to routine immunization services: if there are pockets of unvaccinated children, disease can spread among susceptible people. As poliovirus spread internationally, it has been declared by WHO as a public health emergency of international concern since 2014. For this reason, the Ministry of Health (MOH) urgently teamed up with WHO to contain it. 

Cooperation on three levels for one cause

Relying on expertise and capacities of the three-levels of the Organization, WHO utilized global, regional and local resources to support the outbreak response in Malaysia. First, it assembled a team of experts, who assessed risks; surveilled the circulation of the poliovirus; provided supplemental immunizations; managed vaccines and supported risk communication. The team gave recommendations such as defining the target population as all children under the age of 13, who have not been immunized before. Another recommendation expanded surveillance from 6 to 66 environmental sampling sites across Malaysia. As a result, the country ensured early detection of the virus circulation. Second, the MOH and WHO joined forces in procuring vaccines, with WHO supplying 2.5 million doses of monovalent OPV-2 vaccine and the MOH purchasing the necessary quantities of bivalent OPV-1, 3 vaccine. Yet, before the work was done, it had to be revisited due to the onset of the COVID-19 pandemic. This is where WHO supported Malaysia in adjusting initial plans to include infection prevention and control measures, physical distancing and related preventive measures. For example, house-to-house immunization shifted to fixed sites, making space for drive-through and mobile clinics. Although COVID-19 made the polio response temporarily slower, timely adoption of public health measures ensured it did not stop it.

Inclusive immunization is a success factor

As a result, Malaysia immunized more than 90% of children in the area with supplemental immunizations.

Since March 2020, there has been no cVDPV detected in the country. In addition to the efficient outbreak response, there was another success factor: equity and human rights. By providing vaccination to non-citizens under the same conditions as for citizens, Malaysia walked the talk of leaving no one behind.

Photo caption: Health care worker equipped with personal protective equipment vaccinates a child in a school.

Photo credit: State Health Department Sabah