Health authorities in Mozambique declared an outbreak of wild poliovirus last Wednesday (18 May) after confirming that a child in the country’s north-eastern Tete province had contracted the disease.
This marks the second imported case of wild poliovirus in southern Africa this year, after an outbreak in Malawi in mid-February, said the World Health Organisation’s (WHO) Regional Office for Africa.
The lone case so far, is the country’s first since 1992. The infected child began experiencing the onset of paralysis in late March. Genomic sequencing analysis indicates that the newly confirmed case is linked to a strain that had been circulating in Pakistan in 2019, similar to the case reported in Malawi this year, WHO noted.
Polio is transmitted mainly via contaminated water and food, or through contact with an infected person. The virus can cause paralysis, which is sometimes fatal.
The case in Mozambique and the earlier one in Malawi do not affect Africa’s wild poliovirus-free certification because the virus strain is not indigenous, the WHO stressed.
Africa was declared free of indigenous wild polio in August 2020 after eliminating all forms of wild polio from the region.
“The detection of another case of wild polio virus in Africa is greatly concerning, even if it’s unsurprising, given the recent outbreak in Malawi. However, it shows how dangerous this virus is and how quickly it can spread,” said Dr Matshidiso Moeti, WHO regional director for Africa.
“We are supporting southern African governments to step up the polio fight including carrying out large-scale, effective vaccination campaigns.”
An investigation is under way in Mozambique to determine the extent of the risk posed by the new wild poliovirus case and the targeted responses needed. Preliminary analysis of samples collected from three contacts of the newly-detected case, were all negative for wild poliovirus type 1, said WHO.
Mozambique recently carried out two mass vaccination campaigns – in response to the Malawi outbreak – in which 4.2m children were vaccinated against the disease.
Efforts are under way to help strengthen disease surveillance in Malawi, Mozambique, Tanzania, Zambia and Zimbabwe. All of those countries will continue with mass vaccinations, with plans to reach 23m children five and younger with the polio vaccine in the weeks ahead.
UN News article – First polio outbreak in 30 years declared in Mozambique (Open access)
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