Strongyloidiasis in northern Vietnam: epidemiology, clinical characteristics and molecular diagnosis of the causal agent

Abstract Background Strongyloidiasis is a health problem in Vietnam, but appropriate information is still limited. The aim of this study was to determine the prevalence, geographical distribution, epidemiological aspects, symptoms and other health indicators of Strongyloides stercoralis infections i...

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Main Authors: Nguyen Van De, Pham Ngoc Minh, Le Van Duyet, Santiago Mas-Coma
Format: Article
Language:English
Published: BMC 2019-11-01
Series:Parasites & Vectors
Subjects:
Online Access:http://link.springer.com/article/10.1186/s13071-019-3776-1
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author Nguyen Van De
Pham Ngoc Minh
Le Van Duyet
Santiago Mas-Coma
author_facet Nguyen Van De
Pham Ngoc Minh
Le Van Duyet
Santiago Mas-Coma
author_sort Nguyen Van De
collection DOAJ
description Abstract Background Strongyloidiasis is a health problem in Vietnam, but appropriate information is still limited. The aim of this study was to determine the prevalence, geographical distribution, epidemiological aspects, symptoms and other health indicators of Strongyloides stercoralis infections in patients from 27 provinces of northern Vietnam attending the Hanoi Medical University Hospital during 2016 and 2017. Methods Blood samples of 2000 patients were analyzed for S. stercoralis infection with an IgG ELISA test. Seroprevalence was analyzed by gender, age group, locality of origin (rural or urban areas) and symptoms. Stools from the seropositive patients were examined for the detection of worms which were subsequently used for species identification by morphology and rDNA ITS1 sequencing. Results A seroprevalence of 20% was detected, showing an increasing prevalence from young to older age groups but without significant gender difference. Seroprevalence was higher in rural areas than in urban areas, both in general and individually in all provinces without exception, and lower in the mountainous areas than in the large valley lowlands. The follow-up of the 400 patients showed eosinophilia in 100% of cases, diarrhoea in 64.5%, digestion difficulties in 58.0%, stomachache in 45.5%, stomach and duodenal ulcers in 44.5%, itching in 28.0% and fever in 9.5%. The prevalence of symptoms and signs were also higher in older age groups than in younger age groups. Worms were detected in stools of 10.5% of the patients. Sequencing of a 501-bp nuclear ribosomal DNA ITS1 fragment allowed for the verification of infection by Strongyloides stercoralis. Conclusions To our knowledge, this study is the largest survey of human strongyloidiasis in Vietnam so far and the first molecular identification of this nematode species in this country. Long-term chronicity may probably be usual in infected subjects, mainly in the older age groups.
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spelling doaj.art-f9bae7e5b355413ba883e3184a5887152022-12-22T01:04:49ZengBMCParasites & Vectors1756-33052019-11-0112111210.1186/s13071-019-3776-1Strongyloidiasis in northern Vietnam: epidemiology, clinical characteristics and molecular diagnosis of the causal agentNguyen Van De0Pham Ngoc Minh1Le Van Duyet2Santiago Mas-Coma3Hanoi Medical UniversityHanoi Medical UniversityNational Hospital of Tropical Diseases 78 Giai PhongDepartamento de Parasitología, Facultad de Farmacia, Universidad de ValenciaAbstract Background Strongyloidiasis is a health problem in Vietnam, but appropriate information is still limited. The aim of this study was to determine the prevalence, geographical distribution, epidemiological aspects, symptoms and other health indicators of Strongyloides stercoralis infections in patients from 27 provinces of northern Vietnam attending the Hanoi Medical University Hospital during 2016 and 2017. Methods Blood samples of 2000 patients were analyzed for S. stercoralis infection with an IgG ELISA test. Seroprevalence was analyzed by gender, age group, locality of origin (rural or urban areas) and symptoms. Stools from the seropositive patients were examined for the detection of worms which were subsequently used for species identification by morphology and rDNA ITS1 sequencing. Results A seroprevalence of 20% was detected, showing an increasing prevalence from young to older age groups but without significant gender difference. Seroprevalence was higher in rural areas than in urban areas, both in general and individually in all provinces without exception, and lower in the mountainous areas than in the large valley lowlands. The follow-up of the 400 patients showed eosinophilia in 100% of cases, diarrhoea in 64.5%, digestion difficulties in 58.0%, stomachache in 45.5%, stomach and duodenal ulcers in 44.5%, itching in 28.0% and fever in 9.5%. The prevalence of symptoms and signs were also higher in older age groups than in younger age groups. Worms were detected in stools of 10.5% of the patients. Sequencing of a 501-bp nuclear ribosomal DNA ITS1 fragment allowed for the verification of infection by Strongyloides stercoralis. Conclusions To our knowledge, this study is the largest survey of human strongyloidiasis in Vietnam so far and the first molecular identification of this nematode species in this country. Long-term chronicity may probably be usual in infected subjects, mainly in the older age groups.http://link.springer.com/article/10.1186/s13071-019-3776-1Strongyloides stercoralisEpidemiologyGeographical distributionSymptomatologyDiagnosisITS1 sequence
spellingShingle Nguyen Van De
Pham Ngoc Minh
Le Van Duyet
Santiago Mas-Coma
Strongyloidiasis in northern Vietnam: epidemiology, clinical characteristics and molecular diagnosis of the causal agent
Parasites & Vectors
Strongyloides stercoralis
Epidemiology
Geographical distribution
Symptomatology
Diagnosis
ITS1 sequence
title Strongyloidiasis in northern Vietnam: epidemiology, clinical characteristics and molecular diagnosis of the causal agent
title_full Strongyloidiasis in northern Vietnam: epidemiology, clinical characteristics and molecular diagnosis of the causal agent
title_fullStr Strongyloidiasis in northern Vietnam: epidemiology, clinical characteristics and molecular diagnosis of the causal agent
title_full_unstemmed Strongyloidiasis in northern Vietnam: epidemiology, clinical characteristics and molecular diagnosis of the causal agent
title_short Strongyloidiasis in northern Vietnam: epidemiology, clinical characteristics and molecular diagnosis of the causal agent
title_sort strongyloidiasis in northern vietnam epidemiology clinical characteristics and molecular diagnosis of the causal agent
topic Strongyloides stercoralis
Epidemiology
Geographical distribution
Symptomatology
Diagnosis
ITS1 sequence
url http://link.springer.com/article/10.1186/s13071-019-3776-1
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