Nigeria sees spike in cases of Mutant Poliovirus in 27 states
Twenty-Seven states and the Federal Capital Territory (FCT) have reported an outbreak of Circulating Mutant Poliovirus Type 2 (cMPV2), and the total confirmed cases in the country is 395, the National Primary Healthcare Development Agency stated on Thursday.
cMPV2 is a form of polio that often occurs due to low immunization rates within communities. The Global Polio Eradication Initiative said the virus can mutate and take on a form that can cause paralysis just like the wild poliovirus.
Recently, the World Health Organisation (WHO) expressed concern that Nigeria is causing the virus to spread to other countries. The health body also expressed concerns about the poor quality of supplementary immunisation activities conducted to date and routine immunisation and urged the Nigerian government to focus its efforts to address these factors.
It would be recalled that Nigeria and the African region were certified Wild Polio Virus (WPV) free in 2020, following a verification and certification process by the African Regional Commission for the Certification of Poliomyelitis Eradication (ARCC) which spanned three years of no detection of WPV. In September 2021, the NPHCDA announced an outbreak of vaccine-derived poliovirus across 12 states with 121 cases, a development that put the polio-free status under threat.
The NPHCDA however informed that no cases of Wild Polio Virus (WPV) have been reported anywhere in the country since the last case in 2016.
cMPV2 outbreaks are caused by immunity gaps in children due to several reasons, including low routine immunization coverage, and missing children during immunization campaigns. The suspension of several polio campaigns and other health programmes in 2020, as well as disruptions to routine immunization because of the COVID-19 pandemic, created further immunity gaps which led to new and wider outbreaks and further increased transmission of the circulating mutant poliovirus both globally and within Nigeria.
The viruses thrive in areas with poor sanitation, open defecation, and inadequate access to clean drinking water. These have allowed the virus to be easily transmitted from one person to another through contaminated water and poor sewage disposal.
Malnutrition occasioned by increasing poverty is also a predisposing factor in exposed children. These non-wild polioviruses which originated because of normal changes in the reproduction of viruses in the environment are not as virulent as WPV and are also being reported in many other countries.
The NPHCDA informed that Nigeria has already acquired new tools and resources to ensure the outbreaks are contained through very robust outbreak responses using the novel Oral Polio Vaccine (nOPV2) which has been shown to be effective in halting the spread of the cMPV2.
“All 36 States and FCT have completed at least one nOPV2 Outbreak Response (OBR). Several other rounds of the OBR as well as other campaigns to improve the mucosal immunity of children aged o-5 years old using Injectable Polio Vaccine (IPV) have also been planned for this year. Efforts are also being ramped up to increase routine immunization coverage beyond pre-COVID values,” Fasial Shuaib, Executive Director, NPHCDA said in a statement.
“NPHCDA assures Nigerians that the Agency and Partners will continue to conduct surveillance and vaccination campaigns to prevent and contain any possible importation of the Wild Polio Virus into the country,” he added.