Tomori Oyewale
World Health Organization-Africa Region, Harare, Zimbabwe.
Crit Rev Clin Lab Sci. 2004;41(4):391-427. doi: 10.1080/10408360490497474.
Despite the availability of a safe and efficacious vaccine, yellow fever (YF) remains a disease of significant public health importance, with an estimated 200,000 cases and 30,000 deaths annually. The disease is endemic in tropical regions of Africa and South America; nearly 90% of YF cases and deaths occur in Africa. It is a significant hazard to unvaccinated travelers to these endemic areas. Virus transmission occurs between humans, mosquitoes, and monkeys. The mosquito, the true reservoir of YF, is infected throughout its life, and can transmit the virus transovarially through infected eggs. Man and monkeys, on the other hand, play the role of temporary amplifiers of the virus available for mosquito infection. Recent increases in the density and distribution of the urban mosquito vector, Aedes aegypti, as well as the rise in air travel increase the risk of introduction and spread of yellow fever to North and Central America, the Caribbean, the Middle East, Asia, Australia, and Oceania. It is an acute infectious disease characterized by sudden onset with a two-phase development, separated by a short period of remission. The clinical spectrum of yellow fever varies from very mild, nonspecific, febrile illness to a fulminating, sometimes fatal disease with pathognomic features. In severe cases, jaundice, bleeding diathesis, with hepatorenal involvement are common. The case fatality rate of severe yellow fever is 50% or higher. The pathogenesis and pathophysiology of the disease are poorly understood and have not been the subject of modern clinical research. There is no specific treatment for YF, making the management of YF patients extremely problematic. YF is a zoonotic disease that cannot be eradicated, therefore instituting preventive vaccination through routine childhood vaccination in endemic countries, can significantly reduce the burden of the disease. The distinctive properties of lifelong immunity after a single dose of yellow fever vaccination are the basis of the new applications of yellow fever 17D virus as a vector for foreign genes, "the chimeric vaccine,' and the promise of developing new vaccines against other viruses, and possibly against cancers.
尽管有安全有效的疫苗，但黄热病仍然是一种具有重大公共卫生意义的疾病，估计每年有20万例病例和3万例死亡。该病在非洲和南美洲的热带地区流行；近90%的黄热病病例和死亡发生在非洲。对于前往这些流行地区且未接种疫苗的旅行者来说，这是一个重大风险。病毒在人类、蚊子和猴子之间传播。蚊子是黄热病的真正宿主，其一生都可感染病毒，并能通过受感染的卵经卵巢传播病毒。另一方面，人类和猴子则充当可供蚊子感染的病毒的临时扩增宿主。城市病媒埃及伊蚊的密度和分布最近有所增加，以及航空旅行的增多，增加了黄热病传入和传播到北美洲、中美洲、加勒比地区、中东、亚洲、澳大利亚和大洋洲的风险。它是一种急性传染病，其特点是突然发病，呈两阶段发展，中间有一段短暂的缓解期。黄热病的临床症状范围从非常轻微、非特异性的发热疾病到具有典型特征的暴发性、有时致命的疾病。在严重病例中，黄疸、出血倾向以及肝肾受累很常见。严重黄热病的病死率为50%或更高。该病的发病机制和病理生理学了解甚少，尚未成为现代临床研究的主题。黄热病没有特效治疗方法，这使得黄热病患者的管理极具挑战性。黄热病是一种人畜共患病，无法根除，因此在流行国家通过儿童常规疫苗接种进行预防性疫苗接种，可显著减轻该病的负担。单剂量黄热病疫苗接种后产生终身免疫的独特特性，是黄热病17D病毒作为外源基因载体新应用（“嵌合疫苗”）的基础，也是开发针对其他病毒甚至可能针对癌症的新疫苗的希望所在。
