Herrera-Basto E, Prevots D R, Zarate M L, Silva J L, Sepulveda-Amor J
Directorate of Epidemiology, Ministry of Health, Mexico City, Mexico.
Am J Trop Med Hyg. 1992 Jun;46(6):649-53. doi: 10.4269/ajtmh.1992.46.649.
An outbreak of classical dengue fever occurred from March to August 1988 in the city of Taxco, Guerrero State, Mexico. Taxco is at an elevation of 1,700 meters above sea level, and this study represents the highest altitude at which an outbreak of dengue has been documented. An investigation was conducted to obtain serologic confirmation of dengue infection, determine the extent of the outbreak, and identify risk factors for dengue illness. Toxorhynchites cell lines were used for viral isolation, and hemagglutination inhibition was used to measure anti-dengue antibody titers. The case definition used in the investigation was any person with fever, headache, myalgias, and arthralgias, or rash or retroocular pain. Dengue virus type 1 was isolated from five acute cases. Of 1,686 persons living in the affected area, 42% (715) met the case definition. Large (200-liter) water containers were significantly associated with infection (relative risk = 1.7, 95% confidence interval 1.5-1.9). The effect of altitude on epidemic transmission is most likely modulated by seasonal temperatures. The epidemiologic and serologic confirmation of a dengue outbreak at 1,700 meters above sea level represents the capability of Aedes aegypti to adapt to new environments, and the potential for epidemic spread in cities at comparable altitudes or higher.
1988年3月至8月，墨西哥格雷罗州塔斯科市爆发了经典登革热疫情。塔斯科市海拔1700米，本研究是有记录的登革热疫情发生的最高海拔地区。开展了一项调查，以获得登革热感染的血清学确认，确定疫情的范围，并确定登革热疾病的危险因素。使用巨蚊细胞系进行病毒分离，并采用血凝抑制试验检测抗登革热抗体滴度。调查中使用的病例定义为任何出现发热、头痛、肌痛、关节痛，或皮疹或眼球后疼痛的人。从5例急性病例中分离出1型登革热病毒。在受影响地区居住的1686人中，42%（715人）符合病例定义。大型（200升）储水容器与感染显著相关（相对危险度=1.7，95%置信区间1.5-1.9）。海拔对疫情传播的影响很可能受季节性温度调节。在海拔1700米处登革热疫情的流行病学和血清学确认表明埃及伊蚊有能力适应新环境，以及在海拔相当或更高的城市中疫情传播的可能性。
