On Jul. 28, 2023, the World Health Organization reported Circulating vaccine-derived poliovirus type 2 (cVDPV2) – United Republic of Tanzania, and Kenya.

On 4 July 2023, the Ministry of Health of the United Republic of Tanzania notified WHO of the detection of circulating vaccine-derived poliovirus type 2 (cVDPV2) in the country.

On 11 July 2023, WHO received an official report regarding the detection of a circulating vaccine-derived poliovirus type 2 (cVDPV2) in two acute flaccid paralysis (AFP) cases and two asymptomatic healthy children community contacts from Hagadera refugee camp, in Kenya, the second largest refugee camp in the world with over 100 000 refugees.