The Wild Polio Virus (WPV) has 3 serotypes (1, 2, 3), considered eradicated in many countries, but a few poorly resourced countries still report cases. According to The Guardian (2022), WPV2 and WPV3 are largely eradicated worldwide, and only Pakistan and Afghanistan remain endemic regions for WPV1. The Global Polio Eradication Initiative (GPEI) has helped eradicate this disability causing WPV (WHO, 2022a). However, surveillance efforts often report cases of vaccine-derived polio in many settings (WHO, 2022b). Poliovirus is a single-stranded RNA enterovirus that is primarily fecal-orally transmitted (WHO, 2022a). WPV causes paralytic poliomyelitis that presents with generalized weakness, followed by flaccid paralysis (The Guardian, 2022). Thus massive vaccination has helped curb poliomyelitis, which is a debilitating infection.
The latest cases of WPV have been in poorly resourced settings. For the first time in 30 years, Malawi reported its first case of WPV since 1992 within its capital of Lilongwe in March 2022 (The Guardian, 2022). The case came at a backdrop of the region being declared free of the wild poliovirus in August 2020 (WHO, 2022a). The good news is that the WHO upheld the region’s certification as free of wild polio, linking the case to the Malawian WPV1 variant to the one circulating in Pakistan’s Sindh province since 2019 (The Guardian, 2022). However, the case sparked concerns of a looming outbreak, and and interregional surveillance recommended mass vaccination for more than the 23 million children under 5 years in neighboring Mozambique, Tanzania, Zambia, and Zimbabwe (WHO, 2022b). The recently produced Enhanced Polio Inactivated Vaccine is currently being given as the first shot to prevent the emergence of vaccine-derived polio. Subsequently, vaccinations will use the oral polio vaccine (OPV).
With the possibility of a regional outbreak in the offing, it is hoped that the meticulously planned and coordinated surveillance and vaccination in the southern African countries will extinguish this threat over the four months since the case was in the capital of Malawi (The Guardian, 2022). Africa last reported WPV in northern Nigeria in 2016, and there were only 5 cases in 2021. Thus, many global partners are working together to assess and mitigate the situation in Malawi, using innovative vaccination campaign solutions (WHO, 2022a). The goal has always been to ensure that all children are polio-free since it’s a leading cause of preventable paralysis and disability.