Cryptosporidium hominis Is a Newly Recognized Pathogen in the Arctic Region of Nunavik, Canada: Molecular Characterization of an Outbreak.
Cryptosporidium hominis Is a Newly Recognized Pathogen in the Arctic Region of Nunavik, Canada: Molecular Characterization of an Outbreak.
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DOI：
10.1371/journal.pntd.0004534
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发表时间：
2016-04
影响因子：
3.8
通讯作者：
Yansouni CP
中科院分区：
文献类型：
--
作者：
Thivierge K;Iqbal A;Dixon B;Dion R;Levesque B;Cantin P;Cédilotte L;Ndao M;Proulx JF;Yansouni CP
隐孢子虫是低资源环境中儿童腹泻的主要原因，并一再与身体和认知发育受损有关。2013年5月，在魁北克努纳维克的北极地区发现了由人隐孢子虫引起的腹泻疫情。人类隐孢子虫病的传播在这一地区以前是未知的，以前的研究很少在北极其他地方报道。我们报告了加拿大北极地区多村庄隐孢子虫爆发的临床、分子和流行病学细节。我们对2013年4月至2014年4月期间发病的病例进行了描述性研究，调查了隐孢子虫病的发生情况。病例定义为任何年龄的努纳维克居民，表现为任何持续时间的腹泻，在专门的参考实验室通过粪便显微镜检查检测到隐孢子虫卵囊。在283人中的51人的粪便中鉴定出隐孢子虫。总体年发病率为420 /100 000居民。5岁以下儿童的感染率最高（1，290/100，000人）。通过对60 kDa糖蛋白（gp 60）基因的DNA序列分析，确定了51例中14例粪便标本的遗传亚型。序列与C.所有病例都有人类亚型ID没有发现常见的食物或水源感染。在这一北极地区首次观察到的人类隐孢子虫病爆发中，所看到的高IR引起了人们对因纽特社区儿童生长和发育可能产生的长期影响的担忧，因纽特社区面临着无数其他挑战，如过度拥挤和粮食不安全。病例的时间和地理分布，以及C。人亚型Id，提示人传人而不是人畜共患病传播。及时诊断的障碍延迟了在这种偏远环境下对人类隐孢子虫病的认识。2013年年中，在魁北克努纳维克的北极地区发现了由隐孢子虫引起的中度至重度腹泻疫情，主要影响幼儿。隐孢子虫是低资源环境中儿童腹泻的主要原因，但以前在该地区是未知的。这一点很重要，因为隐孢子虫病一再与生长和发育受损有关，并可能与偏远北极社区儿童目前面临的其他挑战相互作用，如过度拥挤和粮食不安全。虽然北极的动物以前被发现藏有隐孢子虫，它可以感染动物和人类，但我们发现在受影响的人的粪便中鉴定出的隐孢子虫都属于C种。人型流感病毒只会感染人类连同病例的时间和地理分布，这表明这次疫情中的隐孢子虫病是人与人之间传播的，而不是通过与动物接触获得的。隐孢子虫感染在北极社区的出现可能会对公共卫生产生影响，而不仅仅是腹泻的发生。
Cryptosporidium is a leading cause of childhood diarrhea in low-resource settings, and has been repeatedly associated with impaired physical and cognitive development. In May 2013, an outbreak of diarrhea caused by Cryptosporidium hominis was identified in the Arctic region of Nunavik, Quebec. Human cryptosporidiosis transmission was previously unknown in this region, and very few previous studies have reported it elsewhere in the Arctic. We report clinical, molecular, and epidemiologic details of a multi-village Cryptosporidium outbreak in the Canadian Arctic. We investigated the occurrence of cryptosporidiosis using a descriptive study of cases with onset between April 2013 and April 2014. Cases were defined as Nunavik inhabitants of any age presenting with diarrhea of any duration, in whom Cryptosporidium oocysts were detected by stool microscopy in a specialised reference laboratory. Cryptosporidium was identified in stool from 51 of 283 individuals. The overall annual incidence rate (IR) was 420 / 100,000 inhabitants. The IR was highest among children aged less than 5 years (1290 /100,000 persons). Genetic subtyping for stool specimens from 14/51 cases was determined by DNA sequence analysis of the 60 kDa glycoprotein (gp60) gene. Sequences aligned with C. hominis subtype Id in all cases. No common food or water source of infection was identified. In this first observed outbreak of human cryptosporidiosis in this Arctic region, the high IR seen is cause for concern about the possible long-term effects on growth and development of children in Inuit communities, who face myriad other challenges such as overcrowding and food-insecurity. The temporal and geographic distribution of cases, as well as the identification of C. hominis subtype Id, suggest anthroponotic rather than zoonotic transmission. Barriers to timely diagnosis delayed the recognition of human cryptosporidiosis in this remote setting. In mid-2013, an outbreak of moderate-to-severe diarrhea caused by Cryptosporidium was identified in the Arctic region of Nunavik, Quebec, and it predominantly affected young children. Cryptosporidium is a leading cause of childhood diarrhea in low-resource settings, but was previously unknown in this region. This is important because cryptosporidiosis has been repeatedly associated with impaired growth and development, and may interact with other challenges currently faced by children in remote Arctic communities, such as overcrowding and food-insecurity. Although animals in the Arctic have previously been found to harbour Cryptosporidium parvum, which can infect both animals and humans, we found that the Cryptosporidium identified in the stool of affected people all belonged to the species C. hominis, which is only known to infect humans. Together with the temporal and geographic distribution of cases, this suggests that cryptosporidiosis in this outbreak was transmitted person-to-person, rather than acquired from contact with animals. The emergence of Cryptosporidium infections in Arctic communities may have public health impacts beyond the occurrence of diarrhea.