Sanders E J, Marfin A A, Tukei P M, Kuria G, Ademba G, Agata N N, Ouma J O, Cropp C B, Karabatsos N, Reiter P, Moore P S, Gubler D J
Virus Research Centre, Kenya Medical Research Institute, Nairobi.
Am J Trop Med Hyg. 1998 Oct;59(4):644-9. doi: 10.4269/ajtmh.1998.59.644.
Outbreaks of yellow fever (YF) have never been recorded in Kenya. However, in September 1992, cases of hemorrhagic fever (HF) were reported in the Kerio Valley to the Kenya Ministry of Health. Early in 1993, the disease was confirmed as YF and a mass vaccination campaign was initiated. Cases of suspected YF were identified through medical record review and hospital-based disease surveillance by using a clinical case definition. Case-patients were confirmed serologically and virologically. We documented 55 persons with HF from three districts of the Rift Valley Province in the period of September 10, 1992 through March 11, 1993 (attack rate = 27.4/100,000 population). Twenty-six (47%) of the 55 persons had serologic evidence of recent YF infection, and three of these persons were also confirmed by YF virus isolation. No serum was available from the other 29 HF cases. In addition, YF virus was isolated from a person from the epidemic area who had a nonspecific febrile illness but did not meet the case definition. Five patients with confirmed cases of YF died, a case-fatality rate of 19%. Women with confirmed cases of YF were 10.9 times more likely to die than men (P = 0.010, by Fisher's exact test). Of the 26 patients with serologic or virologic evidence of YF, and for whom definite age was known, 21 (81%) were between 10 and 39 years of age, and 19 (73%) were males. All patients with confirmed YF infection lived in rural areas. There was only one instance of multiple cases within a single family, and this was associated with bush-clearing activity. This was the first documented outbreak of YF in Kenya, a classic example of a sylvatic transmission cycle. Surveillance in rural and urban areas outside the vaccination area should be intensified.
肯尼亚从未有过黄热病（YF）暴发的记录。然而，1992年9月，肯尼亚卫生部接到报告，在克里奥河谷出现了出血热（HF）病例。1993年初，该疾病被确诊为黄热病，并启动了大规模疫苗接种运动。通过病历审查和基于医院的疾病监测，采用临床病例定义来识别疑似黄热病病例。病例患者通过血清学和病毒学方法得到确诊。我们记录了1992年9月10日至1993年3月11日期间裂谷省三个地区的55例出血热患者（发病率=27.4/10万人口）。55例患者中有26例（47%）有近期感染黄热病的血清学证据，其中3例还通过黄热病病毒分离得到确诊。另外29例出血热病例没有血清样本。此外，从疫区一名患有非特异性发热疾病但不符合病例定义的人身上分离出了黄热病病毒。5例确诊黄热病病例死亡，病死率为19%。确诊黄热病病例的女性死亡可能性比男性高10.9倍（通过Fisher精确检验，P=0.010）。在26例有黄热病血清学或病毒学证据且年龄明确的患者中，21例（81%）年龄在10至39岁之间，19例（73%）为男性。所有确诊感染黄热病的患者都生活在农村地区。在一个家庭中仅出现过一例多病例情况，且这与砍伐丛林活动有关。这是肯尼亚首次有记录的黄热病暴发，是丛林传播循环的一个典型例子。应加强对疫苗接种区以外农村和城市地区的监测。
