Dean A G, Bates J H, Sorrels C, Sorrels T, Germany W, Ajello L, Kaufman L, McGrew C, Fitts A
Am J Epidemiol. 1978 Jul;108(1):36-46.
An outbreak of histoplasmosis occurred at a county courthouse in Arkansas in July, 1975. Fifty cases were identified by symptoms and positive complement fixation (CF) tests and 18 others by the clinical findings alone. Only three positive CF tests (greater than or equal to 1:8) were found in a control group of 55 unexposed persons of the same age. The attack rate for 84 courthouse employees was 52%. Histoplasma capsulatum was isolated from the sputum of two cases, and from bird droppings which had been dumped from the roof of the courthouse two weeks before the epidemic's peak. Window air conditioners apparently helped to distribute infectious particles throughout the building. Nine exposed people had pulmonary calcifications and a negative tuberculin test that were taken as presumptive evidence of previous histoplasmosis. Five (55%) of these became ill. Exposed persons without pulmonary calcifications had an attack rate of 85%. The reinfected cases during convalescence had higher serum CF titers but not larger histoplasmin skin test diameters than the rest of the cases. A microdroplet aerosol of cooking oil was used to simulate air flow patterns during the exposure, and the results agreed with the hypothesized means of infection.
1975年7月，阿肯色州一座县法院爆发了组织胞浆菌病疫情。50例通过症状和补体结合试验（CF）阳性确诊，另有18例仅通过临床症状确诊。在55名未接触过的同龄对照人群中，仅发现3例CF试验阳性（大于或等于1:8）。84名法院工作人员的发病率为52%。从两例患者的痰液以及疫情高峰前两周从法院屋顶倾倒的鸟粪中分离出荚膜组织胞浆菌。窗式空调显然有助于将感染性颗粒传播到整个大楼。9名接触者有肺部钙化且结核菌素试验阴性，被视为既往感染组织胞浆菌病的推定证据。其中5人（55%）发病。无肺部钙化的接触者发病率为85%。恢复期再次感染的病例血清CF滴度较高，但组织胞浆菌素皮肤试验直径并不比其他病例大。使用食用油微滴气溶胶模拟接触期间的气流模式，结果与假设的感染途径相符。
