Circulating vaccine-derived poliovirus type 2 (cVDPV2) has been detected in Algeria, highlighting the ongoing global challenge of polio eradication. While oral polio vaccines are effective, in under-immunized communities, the weakened virus can mutate and spread, leading to cVDPV outbreaks. This situation underscores the need for strengthened surveillance, vaccination coverage, and international cooperation to prevent resurgence and protect public health.
When immunity weakens, the virus returns—vaccinate to eliminate
– Global Polio Watch
1. What Is cVDPV2?
cVDPV2 is a rare strain of poliovirus that mutates from the weakened virus in oral polio vaccines (OPV). While OPV helps prevent polio, in under-immunized populations, the weakened virus can mutate and regain strength. This mutated virus can spread and cause paralysis, just like the wild poliovirus. It highlights the importance of full vaccination coverage.
2. Algeria’s Reported Case
In 2025, Algeria reported a confirmed case of cVDPV2 in a child, prompting an urgent health investigation. The case was linked to a poliovirus strain previously detected in another country, indicating cross-border transmission. This underscores the importance of regional cooperation and surveillance. Early detection is crucial to prevent wider outbreaks.
3. Why Is This Concerning?
Though rare, cVDPV2 can cause outbreaks in communities with low immunization rates. The virus can circulate silently before symptoms appear, making control efforts difficult. Inadequate sanitation and healthcare access further worsen the spread. That’s why maintaining high vaccination coverage is non-negotiable.
4. Response and Prevention Measures
Algeria, with support from the WHO and GPEI, launched emergency vaccination drives targeting vulnerable groups. Enhanced wastewater surveillance and cross-border coordination were also implemented. Parents are urged to ensure children are fully vaccinated with the inactivated polio vaccine (IPV). Global eradication is only possible through consistent immunization efforts.
- Tags:
- Vaccine
