By NewsDesk @infectiousdiseasenews
The West African country of Guinea reported the first polio cases in the country. According to the Global Polio Eradication Initiative, eight circulating vaccine-derived poliovirus 2 (cVDPV2) cases were reported in the Kankan Region in the eastern part of the country.
The GPEI says Vaccine-derived polioviruses (VDPVs) are rare strains of poliovirus that have genetically mutated from the strain contained in the oral polio vaccine.
The oral polio vaccine contains a live, attenuated (weakened) vaccine-virus. When a child is vaccinated, the weakened vaccine-virus replicates in the intestine and enters into the bloodstream, triggering a protective immune response in the child. Like wild poliovirus, the child excretes the vaccine-virus for a period of six to eight weeks. Importantly, as it is excreted, some of the vaccine-virus may no longer be the same as the original vaccine-virus as it has genetically altered during replication. This is called a vaccine-derived poliovirus.
There has been more than 200 cVDPV cases reported to date in 2020 with the majority reported in Africa.