Burundi Declares an Outbreak of Circulating Poliovirus Type 2

Burundi has declared an outbreak of circulating poliovirus type 2 (CVDPV 2) after eight Poliovirus cases were confirmed on March 17. This is the first such detection in over three decades. The detection of the virus is considered a national public health emergency by the government, which plans to launch a vaccination campaign in the coming weeks to protect all eligible children aged 0–7 years old against the virus.

The cases were confirmed in a 4-year-old boy from the Isale district who had not received polio vaccination, as well as in two other children who were contacts of the 4-year-old boy. In addition, five wastewater samples from environmental surveillance confirmed the presence of the circulating poliovirus type 2.

WHO’s Regional Director for Africa, Dr Matshidiso Moeti, said, “The detection of the circulating poliovirus type 2 shows the effectiveness of the country’s disease surveillance. “We are supporting national efforts to increase polio vaccination rates so that no child is left behind and faces the debilitating effects of polio.”

The most common form of polio in Africa is circulating poliovirus type 2, and outbreaks of this type of poliovirus are the most common in the region, with more than 400 cases reported in 14 countries in 2022. The virus can occur when the weakened strain of the virus contained in the oral polio vaccine circulates among under-immunized populations for long periods.

Still on circulating poliovirus type 2 in Burundi…

With the help of WHO and Global Polio Eradication Initiative (GPEI) partners, health officials have also launched additional epidemiological investigations, including risk assessments, to determine the scope of the outbreak. Burundi is beefing up polio surveillance, with WHO experts on the ground supporting additional sample collection and weighing the feasibility of establishing new environmental surveillance sites to detect silently circulating poliovirus.

Early detection of polio is critical for containing a potential outbreak, as acute flaccid paralysis is defined in children by the sudden onset of weakness or paralysis with reduced muscle tone.