Investigation of a Yellow Fever outbreak in the midst of an ongoing malaria outbreak in Isiolo county, Kenya, March 2022
- Vector-borne
Background
Yellow fever is a viral hemorrhagic disease with high mortality in patients with severe form of disease. The disease is endemic in Kenya, a high-risk country. Kenya’s Ministry of Health declared Yellow Fever outbreak in March 2022 after laboratory detection of cases. This study epidemiologically describes the outbreak.
Methods
We conducted a health facility records review and community active case search for suspected Yellow fever cases. A suspected case was any person who had an acute illness presenting with fever, jaundice, nausea, vomiting, fatigue, headache, or dark urine. We line-listed suspected cases, traced line-listed cases, and collected socio-demographic, clinical, and risk factor information using electronic questionnaire. We collected blood specimens for laboratory testing. We conducted a survey to assess the knowledge, attitude, behaviors, and practices of community members. We calculated measures of central tendency and measures of dispersion for continuous variables. Proportions and percentages were calculated for categorical variables.
Results
Forty-nine suspected cases were identified. Eight cases (16.3%) tested positive for Yellow Fever while 92.3 %(24/26) of the cases tested positive for malaria. One Yellow Fever fatality was recorded (CFR=12.5%). Mean age was 28.6 years (SD=19.0). Males contributed 87.8 %(43/49) of the cases. Livestock herders contributed 40.7%(11/27) of the cases. Fever (100%) and jaundice (89.1%) were the most common clinical presentation. About 29.2% of the cases developed severe disease with average hospital admission of 2.85 days (SD=1.57). None of the cases had received Yellow Fever vaccine. Nearly 70.83% of the community members had some knowledge of Yellow Fever while 52% consistently slept under a mosquito net.
Conclusion
Most of the people with suspected Yellow Fever were young male herders. There was knowledge gap on Yellow fever in the community. We conducted community education and distributed mosquito nets. We recommended enhanced vaccination for Yellow fever.
Yellow fever is a viral hemorrhagic disease with high mortality in patients with severe form of disease. The disease is endemic in Kenya, a high-risk country. Kenya’s Ministry of Health declared Yellow Fever outbreak in March 2022 after laboratory detection of cases. This study epidemiologically describes the outbreak.
Methods
We conducted a health facility records review and community active case search for suspected Yellow fever cases. A suspected case was any person who had an acute illness presenting with fever, jaundice, nausea, vomiting, fatigue, headache, or dark urine. We line-listed suspected cases, traced line-listed cases, and collected socio-demographic, clinical, and risk factor information using electronic questionnaire. We collected blood specimens for laboratory testing. We conducted a survey to assess the knowledge, attitude, behaviors, and practices of community members. We calculated measures of central tendency and measures of dispersion for continuous variables. Proportions and percentages were calculated for categorical variables.
Results
Forty-nine suspected cases were identified. Eight cases (16.3%) tested positive for Yellow Fever while 92.3 %(24/26) of the cases tested positive for malaria. One Yellow Fever fatality was recorded (CFR=12.5%). Mean age was 28.6 years (SD=19.0). Males contributed 87.8 %(43/49) of the cases. Livestock herders contributed 40.7%(11/27) of the cases. Fever (100%) and jaundice (89.1%) were the most common clinical presentation. About 29.2% of the cases developed severe disease with average hospital admission of 2.85 days (SD=1.57). None of the cases had received Yellow Fever vaccine. Nearly 70.83% of the community members had some knowledge of Yellow Fever while 52% consistently slept under a mosquito net.
Conclusion
Most of the people with suspected Yellow Fever were young male herders. There was knowledge gap on Yellow fever in the community. We conducted community education and distributed mosquito nets. We recommended enhanced vaccination for Yellow fever.