Cryptosporidiosis is one of the most important causes of moderate to severe diarrhea and diarrhea-related mortality in children under 2 years of age in low- and middle-income countries. In recent decades, genotyping and subtyping tools have been used in epidemiological studies of human cryptosporidiosis. Results of these studies suggest that higher genetic diversity of Cryptosporidium spp. is present in humans in these countries at both species and subtype levels and that anthroponotic transmission plays a major role in human cryptosporidiosis. Cryptosporidium hominis is the most common Cryptosporidium species in humans in almost all the low- and middle-income countries examined, with five subtype families (namely, Ia, Ib, Id, Ie, and If) being commonly found in most regions. In addition, most Cryptosporidium parvum infections in these areas are caused by the anthroponotic IIc subtype family rather than the zoonotic IIa subtype family. There is geographic segregation in Cryptosporidium hominis subtypes, as revealed by multilocus subtyping. Concurrent and sequential infections with different Cryptosporidium species and subtypes are common, as immunity against reinfection and cross protection against different Cryptosporidium species are partial. Differences in clinical presentations have been observed among Cryptosporidium species and C. hominis subtypes. These observations suggest that WASH (water, sanitation, and hygiene)-based interventions should be implemented to prevent and control human cryptosporidiosis in low- and middle-income countries.

中文翻译：

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低收入和中等收入国家人类隐孢子虫病的分子流行病学

隐孢子虫病是中低收入国家 2 岁以下儿童中度至重度腹泻和腹泻相关死亡率的最重要原因之一。近几十年来，基因分型和分型工具已被用于人类隐孢子虫病的流行病学研究。这些研究的结果表明隐孢子虫的遗传多样性更高。在这些国家的人类中存在物种和亚型水平，并且人为传播在人类隐孢子虫病中起主要作用。人隐孢子虫是最常见的隐孢子虫研究的几乎所有低收入和中等收入国家的人类物种中，大多数地区普遍存在五个亚型科（即 Ia、Ib、Id、Ie 和 If）。此外，这些地区的大多数小隐孢子虫感染是由人为 IIc 亚型家族而不是人畜共患病 IIa 亚型家族引起的。正如多位点亚型所揭示的，人隐孢子虫亚型存在地理隔离。不同隐孢子虫种类和亚型的并发和连续感染很常见，因为对再感染的免疫力和针对不同隐孢子虫种类的交叉保护是部分的。临床表现存在差异隐孢子虫属和人形隐孢子虫亚型。这些观察结果表明，应实施基于 WASH（水、环境卫生和个人卫生）的干预措施，以预防和控制低收入和中等收入国家的人类隐孢子虫病。