The Ministry of Health (MoH) of Kenya reported 453 cases, including 32 laboratory-confirmed cases and 421 suspected cases, of chikungunya from Mombasa County from mid-December 2017 through Feb. 3.
Based on reports from peripheral health facilities, the outbreak spread to the six sub-counties (Changamwe, Jomvu, Kisauni, Likoni, Mvita and Nyali) of Mombasa and one in Kilifi. The majority of suspected cases were reported from Mvita and Likoni in Mombasa.
“Based on the available information, the risk of continued transmission in affected areas and spread to unaffected areas cannot be ruled out,” the World Health Organization (WHO) said in a press release. “…This is the first time that active circulation of chikungunya has been laboratory confirmed in Mombasa. Further sequencing of the circulating virus is therefore needed to better assess the current epidemiologic situation.”
On Dec. 13, 2017, the Kenya Medical Research Institute (KEMRI) arbovirus laboratory in Nairobi received eight blood samples from two private hospitals. Four of these samples tests positive for chikungunya, and four tested positive for dengue by polymerase chain reaction (PCR) analysis.
On Jan. 4 2018, blood samples from 32 additional suspected cases were sent to the KEMRI laboratory. Twenty-seven of these samples tested positive and five samples tested negative for chikungunya by PCR.
An increase in the number of patients presenting to health facilities in Mombasa Country with high-grade fever, joint pain, and general body weakness led to the detection of the outbreak. Approximately 70 percent of cases reported severe joint pain and high-grade fever.
“The scale of this outbreak has likely been underestimated given the under-reporting of cases and low levels of health-seeking behaviors among the affected population,” WHO said.
WHO is supporting the MoH in drafting a chikungunya response plan for Mombasa County and supporting the National Emergency Operations Centre with analyzing data and developing situation reports.
Vector control activities, including eliminating mosquito breeding sites, fogging, and indoor residual spraying are currently ongoing.
Chikungunya outbreak alerts and fact sheets were issued to all health facilities in the affected areas, and community health volunteers distributed information, education and communication materials to households in the area.
“Basic precautions should be taken by people living in and traveling to Mombasa County,” WHO said. “These precautions include the use of repellents, wearing long sleeves and pants and ensuring rooms are fitted with screens to prevent mosquitoes from entering.”
Who also stressed the importance of reducing the number of both natural and artificial water-filled containers that could act as mosquito breeding sites.