Conteas C N, Berlin O G, Lariviere M J, Pandhumas S S, Speck C E, Porschen R, Nakaya T
Division of Gastroenterology, Southern California Permanente Medical Group, Los Angeles 90027, USA.
Am J Trop Med Hyg. 1998 May;58(5):559-61. doi: 10.4269/ajtmh.1998.58.559.
The epidemiology of human microsporidiosis is poorly understood and environmental factors affecting transmission of the organism have not been fully elucidated. Temporal variation in the prevalence of microsporidia in the stool of patients with human immunodeficiency virus (HIV) infection and diarrhea was studied to evaluate the role of water-borne transmission. From January 1993 to December 1996, 8,439 stools from HIV-infected individuals were examined for microsporidia spores in southern California. Yearly positivity rates were 8.8% in 1993, 9.7% in 1994, 6.6% in 1995, and 2.9% in 1996. An analysis for linear trend showed a statistically significant decrease in stool positivity rates over time (chi2 = 81.9, P = 0.001). No significant seasonal variation in the prevalence of microsporidiosis was seen over that time period. These results suggest the constant presence of microsporidia in the environment, rather than a seasonal association with recreational water use or seasonal contamination of the water supply, and a real decrease in yearly prevalence of microsporidia related diarrhea. Factors related to a progressive decrease in prevalence are subjects of future investigation.
人类微孢子虫病的流行病学尚不清楚，影响该病原体传播的环境因素也未完全阐明。为评估水传播的作用，对人类免疫缺陷病毒（HIV）感染且腹泻患者粪便中微孢子虫患病率的时间变化进行了研究。1993年1月至1996年12月，在南加州对8439份HIV感染者的粪便进行了微孢子虫孢子检测。1993年的年阳性率为8.8%，1994年为9.7%，1995年为6.6%，1996年为2.9%。线性趋势分析显示，粪便阳性率随时间有统计学意义的下降（χ2 = 81.9，P = 0.001）。在该时间段内，未观察到微孢子虫病患病率有明显的季节性变化。这些结果表明，环境中持续存在微孢子虫，而非与娱乐用水或供水季节性污染存在季节性关联，且微孢子虫相关腹泻的年患病率确实下降。患病率逐渐下降的相关因素是未来研究的课题。
