Parasitology Department, Evandro Chagas Institute (Surveillance Secretary of Health, Ministry of Health), Belém, Pará, Brazil.
Parasitol Res. 2010 Jan;106(2):377-86. doi: 10.1007/s00436-009-1672-x. Epub 2009 Nov 28.
This was a prospective study carried out during a period over 2 years (May/2006-September/2008) with a cohort of 1,099 individuals of both genders, aged 1 year old and older, from an endemic area of American visceral leishmaniasis (AVL) in Pará state, Brazil. The object was to analyze the prevalence and incidence of human Leishmania (L.) infantum chagasi infection as well as the dynamics evolution of its clinical-immunological profiles prior identified: (1) asymptomatic infection (AI); (2) symptomatic infection (SI = AVL); (3) sub-clinical oligosymptomatic infection (SOI); (4) sub-clinical resistant infection (SRI) and; (5) indeterminate initial infection (III). The infection diagnosis was performed by using both the indirect fluorescent antibody test and leishmanin skin test with amastigotes and promastigotes antigens of L. (L.) i. chagasi, respectively. A total of 187 cases of infection were recorded in the prevalence (17%), 117 in the final incidence (6.9%), and 304 in the accumulated prevalence (26.7%), which provided the following distribution into the clinical-immunological profiles: AI, 51.6%; III, 22.4%; SRI, 20.1%; SOI, 4.3%; and SI (=AVL), 1.6%. The major finding regarding the dynamics evolution of infection was concerned to III profile, from which the cases of infection evolved to either the resistant profiles, SRI (21 cases, 30.8%) and AI (30 cases, 44.1%), or the susceptible SI (=AVL; 1 case, 1.5%); the latter 16 cases remained as III till the end of the study. These results provided the conclusion that this diagnostic approach may be useful for monitoring human L. (L.) i. chagasi infection in endemic area and preventing the high morbidity of severe AVL cases.
这是一项为期两年多的前瞻性研究（2006 年 5 月至 2008 年 9 月），对象为巴西帕拉州一个美洲内脏利什曼病（AVL）流行地区的 1099 名 1 岁以上的男女两性个体。目的是分析人类利什曼原虫（L.）婴儿 Chagasi 感染的流行率和发病率，以及先前确定的临床免疫特征的动态演变：（1）无症状感染（AI）；（2）症状感染（SI=AVL）；（3）亚临床寡症状感染（SOI）；（4）亚临床耐药感染（SRI）；（5）初始感染不确定（III）。感染诊断分别采用间接荧光抗体试验和利什曼原虫皮肤试验，用利什曼原虫婴儿 Chagasi 的鞭毛体和前鞭毛体抗原。在流行率中记录了 187 例感染病例（17%），在最终发病率中记录了 117 例（6.9%），在累积流行率中记录了 304 例（26.7%），分别分配到临床免疫特征中：AI，51.6%；III，22.4%；SRI，20.1%；SOI，4.3%；和 SI（=AVL），1.6%。关于感染动态演变的主要发现涉及 III 型，从 III 型病例的感染演变到耐药型，SRI（21 例，30.8%）和 AI（30 例，44.1%），或易感的 SI（=AVL；1 例，1.5%）；其余 16 例在研究结束时仍为 III 型。这些结果得出结论，这种诊断方法可用于监测流行地区人类利什曼原虫（L.）婴儿 Chagasi 感染，预防严重 AVL 病例的高发病率。
