在非流行地区,99% 的慢性类圆线虫感染是来自流行地区的移民,特别是难民。[7]Boulware DR, Stauffer WM, Hendel-Paterson BR, et al. Maltreatment of Strongyloides infection: case series and worldwide physicians-in-training survey. Am J Med. 2007;120:545.e1-545.e8.http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=17524758http://www.ncbi.nlm.nih.gov/pubmed/17524758?tool=bestpractice.com[8]de Silva S, Saykao P, Kelly H, et al. Chronic Strongyloides stercoralis infection in Laotian immigrants and refugees 7-20 years after resettlement in Australia. Epidemiol Infect. 2002;128:439-444.http://www.ncbi.nlm.nih.gov/pubmed/12113488?tool=bestpractice.com[9]Franco-Paredes C, Dismukes R, Nicolls D, et al. Persistent and untreated tropical infectious diseases among Sudanese refugees in the United States. Am J Trop Med Hyg. 2007;77:633-635.http://www.ncbi.nlm.nih.gov/pubmed/17978062?tool=bestpractice.com[10]Caruana SR, Kelly HA, Ngeow JY, et al. Undiagnosed and potentially lethal parasite infections among immigrants and refugees in Australia. J Travel Med. 2006;13:233-239.http://onlinelibrary.wiley.com/doi/10.1111/j.1708-8305.2006.00045.x/fullhttp://www.ncbi.nlm.nih.gov/pubmed/16884406?tool=bestpractice.com[11]Loutfy MR, Wilson M, Keystone JS, et al. Serology and eosinophil count in the diagnosis and management of strongyloidiasis in a non-endemic area. Am J Trop Med Hyg. 2002;66:749-752.http://www.ajtmh.org/cgi/reprint/66/6/749http://www.ncbi.nlm.nih.gov/pubmed/12224585?tool=bestpractice.com[12]Siddiqui AA, Berk SL. Diagnosis of Strongyloides stercoralis infection. Clin Infect Dis. 2001;33:1040-1047.http://www.ncbi.nlm.nih.gov/pubmed/11528578?tool=bestpractice.com当前在非洲单剂量吡喹酮和阿苯达唑给药并未降低类圆线虫感染率。[13]Sousa-Figueiredo JC, Day M, Betson M, et al. Field survey for strongyloidiasis in eastern Uganda with observations on efficacy of preventive chemotherapy and co-occurrence of soil-transmitted helminthiasis/intestinal schistosomiasis. J Helminthol. 2010;20:1-9.http://www.ncbi.nlm.nih.gov/pubmed/20961473?tool=bestpractice.com
最大的危险因素是皮肤接触含有类圆线虫丝状蚴的感染土壤。
感染具有地方流行性,多见于世界范围内的热带和亚热带地区、美国阿巴拉契亚地区以及某些地中海地区(尤其是西班牙加泰罗尼亚)。
在感染流行地区,农业工作者的慢性感染风险是一般人群的 50 倍以上。[4]Román-Sánchez P, Pastor-Guzmán A, Moreno-Guillén S, et al. High prevalence of Strongyloides stercoralis among farm workers on the Spanish Mediterranean coast. Analysis of the predictive factors of infection in developed countries. Am J Trop Med Hyg. 2003;69:336-340.http://www.ajtmh.org/cgi/content/full/69/3/336http://www.ncbi.nlm.nih.gov/pubmed/14628954?tool=bestpractice.com退伍军人(特别是曾在东南亚或其他热带地区部署)也有风险。[6]Gill GV, Welch E, Bailey JW, et al. Chronic Strongyloides stercoralis infection in former British Far East prisoners of war. QJM. 2004;97:789-795.http://qjmed.oxfordjournals.org/cgi/content/full/97/12/789http://www.ncbi.nlm.nih.gov/pubmed/15569810?tool=bestpractice.com