Yellow fever: outbreak in Kenya

Outbreak reported in Isiolo and Garissa Counties

• This updates the news item of 14 March 2022

Yellow fever is a viral haemorrhagic, vaccine preventable infection, transmitted to monkeys and humans by forest or urban dwelling mosquitoes. There is a risk of yellow fever transmission in parts of Kenya.

On 5 March 2022, the Ministry of Health, Kenya reported a yellow fever outbreak in Isiolo County (a region which falls within the known area of risk for yellow fever transmission). The first case was detected on 12 January 2022 and as of 5 March 2022; a total of 15 cases, with three deaths, had been reported [1].

On 23 July 2022, the Ministry of Health in Kenya posted an update on the outbreak, reporting a total of 111 cases and 12 deaths. A majority of cases (71) have been reported in Isiolo County. However, Garissa County (which is outside of the recognised yellow fever transmission area, and part of the North Eastern Province) has also reported cases [2]. A vaccination campaign has been launched targeting Merti and Garbatula sub-counties in Isiolo as well as Lagdera, Balambala and Garissa sub-counties in Garissa County [2].

These are the first locally acquired cases of yellow fever reported in Kenya since 1995. The first yellow fever outbreak recorded in Kenya was reported from 1992 to 1993 in the Rift Valley Province [3]. Following this outbreak, ten further cases were identified during surveillance between 1993 -1995 [4]. In March 2016, two imported cases were reported in Kenyan nationals arriving from Angola [5].

Advice for travellers

The World Health Organization recommends YF yellow fever vaccination for all travellers aged nine months and older visiting areas with risk of yellow fever transmission [6] unless the vaccine is contraindicated for medical reasons. You should also follow mosquito bite avoidance guidance. If you are visiting Garissa County in North Eastern Province, seek advice from a health professional and check the Country Information page (including the outbreaks and important news sections) for updates.

Be aware that if a country does not have a requirement for an International Certificate of Vaccination or Prophylaxis (ICVP) for yellow fever it does not necessarily mean that there is no risk of yellow fever in that country.

For advice on yellow fever risk and your suitability for vaccination, and yellow fever certificate issues we recommend you contact a Yellow Fever Vaccination Centre. In the UK, travellers can find their nearest Yellow Fever Vaccination Centre by using the YFVC Search Locator.

Specific yellow fever information on risk, vaccine recommendations and certificate requirements for Kenya are available on TravelHealthPro Country Information pages.

Advice for health professionals

Travellers to Kenya must be advised that yellow fever is spread via mosquitos bites and carefully counselled about the importance of following insect bite avoidance measures, day and night, when in Kenya.

When undertaking yellow fever risk assessment, health professionals should use the Yellow fever pre-vaccination checklist and Yellow fever vaccine: contraindications and precautions reminder.

Health professionals should refer to the Country Information page for Kenya, which provides detail relating to risk areas, recommendation for yellow fever vaccination and IHR (2005) certificate requirements.

Health professionals are also encouraged to access the Outbreak Surveillance section where outbreaks details are posted. The NaTHNaC advice line is available for health professionals seeking further advice.