The WHO declared that the strain was linked to one that has been spreading in Pakistan, where it is still endemic.
Malawi's health authorities have declared a polio outbreak after a case was detected in a young child in the capital Lilongwe, the first case of wild poliovirus in Africa in more than five years.
The World Health Organization (WHO) said in a statement on Friday that laboratory analysis showed the strain detected in Malawi was linked to one that has been circulating in Pakistan, where it is still endemic.
"As an imported case from Pakistan, this detection does not affect the African region's wild poliovirus-free certification status," the WHO said.
The WHO stated the African continent could launch a rapid response because of a high level of polio surveillance.
"The last case of wild poliovirus in Africa was identified in northern Nigeria in 2016 and globally there were only five cases in 2021" said Modjirom Ndoutabe, polio coordinator in the WHO's regional office for Africa.
"Any case of wild poliovirus is a significant event and we will mobilise all resources to support the country's response," Ndoutabe added.
Highly infectious disease
Polio is a highly infectious disease that invades the nervous system and can cause total paralysis within hours.
While there is no cure for polio, it can be prevented by administration of a vaccine, the WHO said.
The Global Polio Eradication Initiative said the case in the southern African country was in a three-year-old girl who experienced the onset of paralysis in November last year.
Sequencing of the virus conducted in February by South Africa's National Institute for Communicable Diseases and the US Centers for Disease Control and Prevention confirmed it as type 1 wild poliovirus (WPV1).
"Detection of WPV1 outside the world's two remaining endemic countries, Pakistan and Afghanistan, is a serious concern and underscores the importance of prioritising polio immunisation activities," the Global Polio Eradication Initiative said.
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