Prevalence of Cryptosporidium parvum/hominis, Entamoeba histolytica and Giardia lamblia among Young Children with and without Diarrhea in Dar es Salaam, Tanzania.
Prevalence of Cryptosporidium parvum/hominis, Entamoeba histolytica and Giardia lamblia among Young Children with and without Diarrhea in Dar es Salaam, Tanzania.
复制标题
DOI：
10.1371/journal.pntd.0004125
复制
发表时间：
2015
影响因子：
3.8
通讯作者：
Hanevik K
中科院分区：
文献类型：
--
作者：
Tellevik MG;Moyo SJ;Blomberg B;Hjøllo T;Maselle SY;Langeland N;Hanevik K
虽然肠道寄生虫是腹泻疾病的常见原因，但在坦桑尼亚的儿童中进行的研究很少。本研究旨在调查坦桑尼亚达累斯萨拉姆幼儿中细小隐孢子虫/人隐孢子虫、溶组织内阿米巴原虫和兰第鞭毛虫的流行情况，并确定感染的危险因素。我们对2010年8月至2011年7月在达累斯萨拉姆招募的2岁以下儿童进行了一项无与伦比的病例对照研究。采用PCR技术对三家研究医院的701例腹泻患儿和558例入组前一个月内无腹泻史的对照患儿的粪便标本进行DNA检测和鉴定。小恙虫/人弓形虫感染率为10.4%（人弓形虫84.7%），兰氏弓形虫为4.6%。未检出溶组织芽胞杆菌。病例中隐孢子虫的患病率（16.3%）显著高于对照组（3.1%;P < 0.001; OR = 6.2; 95% CI: 3.7-10.4）。对照组（6.1%）明显高于病例组（3.4%;P = 0.027; OR = 1.8; 95% CI: 1.1-3.1）。隐孢子虫感染在hiv阳性儿童中的发生率（24.2%）高于hiv阴性儿童（3.9%;P < 0.001; OR = 7.9; 95% CI: 3.1-20.5），并且与降雨有关（P < 0.001; OR = 2.41; 95% CI: 1.5-3.8）。在这些病例中，发育迟缓的儿童感染隐孢子虫的风险明显更高（P = 0.011; OR = 2.12; 95% CI: 1.2-3.8）。兰氏螺旋体感染以寒季流行（P = 0.004; OR = 2.2; 95% CI: 1.3 ~ 3.8），以年龄为0 ~ 12月龄的病例多见（P = 0.003; OR = 3.5; 95% CI: 1.5 ~ 7.8）。在7-12个月的儿童中，母乳喂养的儿童感染兰氏杆菌的患病率低于断奶的儿童（P = 0.012）。隐孢子虫感染在患有腹泻的坦桑尼亚儿童中很常见，特别是那些感染艾滋病毒的儿童，并且在雨季感染更为频繁。兰氏螺旋体通常与无症状感染有关，但很少引起明显的腹泻疾病，其患病率随着年龄的增长而增加。腹泻病是幼儿患病和死亡的主要原因。在非洲，超过十分之一的儿童死亡是由这些疾病造成的。隐孢子虫、溶组织内阿米巴原虫和贾第鞭毛虫等寄生虫都是腹泻疾病的常见病因，但对坦桑尼亚儿童中这些肠道寄生虫的研究很少。在这项病例对照研究中，我们在坦桑尼亚达累斯萨拉姆纳入了701例病例和558例对照，年龄均小于2岁。我们通过聚合酶链反应（PCR）评估了细小梭菌/人型梭菌、溶组织梭菌和兰氏梭菌的流行情况，以及它们与人口统计学数据、临床症状、HIV感染状况和季节性等潜在危险因素的关系。14.9%的样本中发现一种或多种寄生虫。分别有10.4%和4.6%的样本检出细小梭菌/人原体和兰氏梭菌，未检出溶组织梭菌。隐孢子虫的流行率很高，特别是在感染艾滋病毒的儿童中，其流行率在雨季增加。在这些病例中，隐孢子虫在发育迟缓的儿童中更常见，尽管目前的研究还不能确定任何因果关系。兰螺旋体在无症状感染中比在明显的腹泻疾病中更常见。随着年龄的增长，G. lamblia的流行率增加，母乳喂养似乎可以保护儿童免受G. lamblia的侵害。本研究提供了坦桑尼亚儿童中这些肠道寄生虫的患病率和临床特征的相关信息。
Although enteroparasites are common causes of diarrheal illness, few studies have been performed among children in Tanzania. This study aimed to investigate the prevalence of Cryptosporidium parvum/hominis, Entamoeba histolytica and Giardia lamblia among young children in Dar es Salaam, Tanzania, and identify risk factors for infection. We performed an unmatched case-control study among children < 2 years of age in Dar es Salaam, recruited from August 2010 to July 2011. Detection and identification of protozoans were done by PCR techniques on DNA from stool specimens from 701 cases of children admitted due to diarrhea at the three study hospitals, and 558 controls of children with no history of diarrhea during the last month prior to enrollment. The prevalence of C. parvum/hominis was 10.4% (84.7% C. hominis), and that of G. lamblia 4.6%. E. histolytica was not detected. The prevalence of Cryptosporidium was significantly higher in cases (16.3%) than in controls (3.1%; P < 0.001; OR = 6.2; 95% CI: 3.7–10.4). G. lamblia was significantly more prevalent in controls (6.1%) than in cases (3.4%; P = 0.027; OR = 1.8; 95% CI: 1.1–3.1). Cryptosporidium infection was found more often in HIV-positive (24.2%) than in HIV-negative children (3.9%; P < 0.001; OR = 7.9; 95% CI: 3.1–20.5), and was also associated with rainfall (P < 0.001; OR = 2.41; 95% CI: 1.5–3.8). Among cases, stunted children had significantly higher risk of being infected with Cryptosporidium (P = 0.011; OR = 2.12; 95% CI: 1.2–3.8). G. lamblia infection was more prevalent in the cool season (P = 0.004; OR = 2.2; 95% CI: 1.3–3.8), and more frequent among cases aged > 12 months (P = 0.003; OR = 3.5; 95% CI: 1.5–7.8). Among children aged 7–12 months, those who were breastfed had lower prevalence of G. lamblia infection than those who had been weaned (P = 0.012). Cryptosporidium infection is common among young Tanzanian children with diarrhea, particularly those living with HIV, and infection is more frequent during the rainy season. G. lamblia is frequently implicated in asymptomatic infections, but rarely causes overt diarrheal illness, and its prevalence increases with age. Diarrheal diseases are a leading cause of disease and deaths among young children. In Africa they contribute to more than one tenth of childhood deaths. Parasites like Cryptosporidium, Entamoeba histolytica and Giardia lamblia are all common causes of diarrheal illness, but there are few studies on these enteroparasites among Tanzanian children. In this case-control study, we included 701 cases and 558 controls, all < 2 years of age, in Dar es Salaam, Tanzania. We assessed the prevalence of C. parvum/hominis, E. histolytica and G. lamblia by PCR, and the association with potential risk factors such as demographic data, clinical symptoms, HIV status and seasonality. One or more parasites were found in 14.9% of the samples. C. parvum/ hominis and G. lamblia were found in 10.4% and 4.6%, respectively, while E. histolytica was not found in any of the samples. The prevalence of Cryptosporidium was high, particularly in children with HIV, and its prevalence increased during the rainy season. Among cases, Cryptosporidium was found more frequently in stunted children, although any causal association could not be established in the current study. G. lamblia was more often implicated in asymptomatic infections than in overt diarrheal illness. The prevalence of G. lamblia increased with age, and breastfeeding seemed to protect the children from G. lamblia. This study presents relevant information about the prevalence and clinical characteristics of these intestinal parasites in Tanzanian children.