McAnulty J M, Fleming D W, Gonzalez A H
Division of Field Epidemiology, Centers for Disease Control and Prevention, Atlanta, Ga 97232.
JAMA. 1994;272(20):1597-600.
To determine the cause of a community-wide outbreak of cryptosporidiosis.
A matched case-control study.
General community of Lane County, Oregon.
Persons with Cryptosporidium detected in their stool from June to October 1992 were identified by contacting laboratories serving the area. Exposures of the first 18 case patients identified were compared with those of 18 age- and neighborhood-matched controls selected from a reverse telephone directory.
Reported exposures to risk factors for cryptosporidiosis and abatement of cryptosporidiosis outbreak.
Fifty-five patients with cryptosporidiosis were detected, including 37 who were the first individuals ill in their households. The case-control study involving the first 18 case patients showed no association between illness and attendance at day care or drinking municipal water or drinking untreated surface waters (river or lake water) in the 2 weeks before onset of illness. However, nine of 18 case patients reported swimming at a local wave pool, compared with none of 18 controls. We ultimately identified 17 case patients who reported swimming at the same wave pool during their incubation periods, whose exposure dates spanned a 2-month period. Inspection of the pool's filtration system did not detect any abnormalities. The outbreak subsided after the pool water was drained and replaced.
This prolonged outbreak of cryptosporidiosis was likely caused by exposure to fecally contaminated wave pool water. Since Cryptosporidium is highly chlorine resistant and inadequately removed by sand filters, such outbreaks may represent an unrecognized hazard of wave pools, where the likelihood of inadvertent water ingestion is high. Such outbreaks may go undetected in areas where cryptosporidiosis is not reportable or laboratory screening is infrequent.
确定社区范围内隐孢子虫病暴发的原因。
一项配对病例对照研究。
俄勒冈州莱恩县的普通社区。
通过联系为该地区服务的实验室，确定了1992年6月至10月粪便中检测出隐孢子虫的人员。将最初确诊的18例病例患者的暴露情况与从反向电话簿中选取的18名年龄和邻里匹配的对照者的暴露情况进行比较。
报告的隐孢子虫病危险因素暴露情况及隐孢子虫病暴发的缓解情况。
共检测出55例隐孢子虫病患者，其中37例是其家庭中首例患病者。涉及最初18例病例患者的病例对照研究表明，疾病与发病前2周内参加日托、饮用市政供水或未经处理的地表水（河水或湖水）之间无关联。然而，18例病例患者中有9例报告在当地的波浪泳池游泳，而18名对照者均未报告。我们最终确定了17例病例患者，他们在潜伏期报告在同一波浪泳池游泳，其暴露日期跨度为2个月。对泳池过滤系统的检查未发现任何异常。泳池排水并换水后，疫情得到缓解。
此次长时间的隐孢子虫病暴发可能是由于接触了受粪便污染的波浪泳池水所致。由于隐孢子虫对氯具有高度抗性且砂滤器不能充分去除，此类暴发可能代表波浪泳池存在未被认识到的危害，在这种泳池中意外摄入水的可能性很高。在隐孢子虫病不可报告或实验室筛查不频繁的地区，此类暴发可能未被发现。
