Yellow fever is back after more than two decades in northern Kenya.
Kenya has declared an epidemic after new cases were reported in the county of Isiolo, according to the statement of the Ministry of Health. Three people have died so far while more than twenty are citizens in the sub-counties of Imerti and Garbatulla to have contracted the virus in the last month.
The last case detected, five years ago at the international airport of Nairobi, did not concern a Kenyan citizen, but a traveler from Angola. But the last risk of epidemic in the Rift Valley regions dates back to 1999. Until the early 1990s, the yellow fever vaccine was mandatory in Kenya, as in 17 other African countries. 
In today's report, Saturday, March 5, Director General of Health Patrick Amoth noted six more cases from test samples conducted by the Kenya Medical Research Institute (KEMRI).
The alert was sent to neighboring counties considered at risk, namely Wajir, Garissa, Marsabit, Meru, Samburu, Baringo, Elgeyo Marakwet, West Pokot and Turkana. At the same time the alert was launched on the national soil, asking to raise the threshold of attention.
Amoth pointed out that the first case was detected on January 12 and since then 15 suspected cases have been identified with symptoms including headache, fever, jaundice, muscle and joint pain. Among the patients, the youngest is an 11-year-old while the oldest is 65 years old. Young adult males make up the majority of those infected.
For now, there are no problems for those traveling in the direction of large cities, nor for coastal destinations. The government is awaiting developments, but it is too early to say if there will be any changes in regulations to enter the country.