Massey University, Institute of Veterinary, Animal and Biomedical Sciences, Palmerston North, New Zealand.
Epidemiol Infect. 2011 Oct;139(10):1542-50. doi: 10.1017/S0950268810002499. Epub 2010 Nov 19.
The occurrence of a gastrointestinal illness among a class of 96 undergraduate veterinary students in New Zealand prompted laboratory and questionnaire-based investigations. Cryptosporidium parvum was the only enteropathogen identified in 4/7 faecal specimens analysed. The C. parvum isolates carried a rare IIa GP60 allele, indicating a point-source outbreak. The infection source could not be microbiologically traced, but the investigation suggested contact with calves during a practical class as the most likely exposure. A total of 25/80 respondents to a questionnaire were defined as cases using a clinical case definition (31% attack rate). The inferred median incubation period was 5 days (range 0-11 days), and the median illness duration was 5-6 days (range 2-23 days), corroborating previous observations in experimental cryptosporidiosis. Disease was self-limiting, characterized by abdominal discomfort, diarrhoea, and in some cases, vomiting. Originating from a rural area and having had previously handled ruminants were associated with a significant risk reduction in males. All the three students who reported chronic use of steroid inhalers for treatment of asthma were cases. This case highlighted, once again, the potential hazard for explosive outbreaks of cryptosporidiosis.
新西兰 96 名兽医专业大学生群体中出现胃肠道疾病，促使开展了实验室和问卷调查研究。7 份粪便样本中有 4 份分析出了微小隐孢子虫。分离出的微小隐孢子虫株携带一种罕见的 IIa 型 GP60 等位基因，表明是点状暴发。虽然未能追踪到感染源，但调查提示在实习课中接触小牛犊可能是最有可能的暴露源。使用临床病例定义（31%的发病率），对 80 份调查问卷中的 25 人进行了病例定义。推断的中位潜伏期为 5 天（范围 0-11 天），中位疾病持续时间为 5-6 天（范围 2-23 天），证实了先前在实验性隐孢子虫病中的观察结果。疾病呈自限性，表现为腹部不适、腹泻，在某些情况下还会呕吐。来自农村地区和之前接触过反刍动物的男性患病风险显著降低。报告曾因哮喘使用类固醇吸入器进行慢性治疗的 3 名学生均为病例。这一案例再次强调了隐孢子虫病暴发的潜在危险。
