Malawi has declared an outbreak of polio after a child in the countryʼs capital, Lilongwe, developed the disease in the first case of the wild polio virus in Africa in more than five years, reports Al Jazeera.
The strain has been linked to one circulating in Pakistan where the virus remains endemic, the World Health Organization said in a statement last Thursday (17 February).
Wild poliovirus (WPV) is the most commonly known form of the poliovirus. Wild polioviruses are naturally occurring isolates known or believed to have circulated persistently in the community. However, there is another form of polio that can spread within communities: circulating vaccine-derived poliovirus, or cVDPV. While cVDPVs are rare, they have been increasing in recent years due to low immunisation rates within communities.
Africa was declared free of wild polio in August 2020, and the WHO said that the new case did not affect that status.
“As long as wild polio exists anywhere in the world all countries remain at risk of importation of the virus,” said Dr Matshidiso Moeti, the WHOʼs regional director for Africa. “After the detection of wild polio in Malawi, weʼre taking urgent measures to forestall its potential spread.”
WHO said it was giving its assistance to Malawi’s health authorities, carrying out a risk assessment and outbreak response and deploying the Global Polio Eradication Initiativeʼs (GPEI) rapid response team. It is also stepping up supplemental immunisation.
“The last case of wild polio virus in Africa was identified in northern Nigeria in 2016 and globally there were only five cases in 2021. Any case of wild polio virus is a significant event and we will mobilise all resources to support the countryʼs response,” said Dr Modjirom Ndoutabe, polio coordinator in the WHO Regional Office for Africa.
Polio is a highly infectious and debilitating disease that is usually spread through contaminated water or food. Invading the nervous system, it can cause total paralysis within hours.
There is no cure for the disease, but an effective vaccine was developed in the 1950s, which has led to its eradication in many parts of the world. The disease remains endemic not only in Pakistan, but also in Afghanistan.
Since 1988, worldwide cases of the virus have dropped by 99%, from more than 350,000 to just five cases in Afghanistan and Pakistan last year, according to GPEI data.
Al Jazeera article – Malawi finds wild polio case; first in Africa in five years (Open access)
GPEI Statement on WPV1 in Malawi: Wild poliovirus type 1 detected in Lilongwe (Open access)
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