In July 2022, an outbreak of Yellow Fever was confirmed in Isiolo and Garissa Counties in Kenya. Suspected cases were also reported in ten other counties, including Samburu, Meru, Wajir, Nakuru, Mombasa, Nairobi, Tana River, Turkana, Trans Nzoia, and Laikipia. As of October 3, 2022, a total of 141 cases with three confirmed positive, eight presumptive positive cases, and 11 deaths were reported, resulting in a CFR of 7.8%.

The outbreak was first reported in January 2022 in Merti Sub County of Isiolo County. Until the end of August 2022, Isiolo County had recorded 71 suspected cases and 7 deaths, while Garissa County recorded one case. Six presumptive positive cases and two confirmed cases were also recorded in Isiolo County.

The epidemiological situation was limited by capacity in the remote areas affected, and the fact that the region had not traditionally been affected by yellow fever in the past. The considerable gaps and the outbreak trend in that context were therefore an indication that more needed to be done with regards to community sensitization, vaccination, and prevention against yellow fever in the two affected counties as they border each other.

The first confirmed case took three weeks, indicating the lengthy process that was undertaken for transportation of samples and laboratory testing. The outbreak was further compounded by the fact that the drought situation added to the vulnerability of the affected communities. Community mobilization and sensitization of the various IPC measures were of paramount importance.

In addition to the Yellow Fever outbreak, an outbreak of Chikungunya was reported in Wajir County in March 2022. A total of 291 cases with five confirmed cases and one death (CFR 0.3%) have been reported since November 2021. The capacity of the remote county health systems was also wanting, hence the need for capacity building.

With the severity of the outbreaks of both Yellow Fever and Chikungunya, there was a need to upscale response actions to avert further spread and morbidity as a result of the diseases. The situation necessitated the need to have a coordinated response of vector-borne diseases affecting the target counties.