Strongyloides stercoralis seroprevalence in Vietnam

Abstract

SUMMARYStrongyloidiasis is a neglected tropical disease caused by the roundworm Strongyloides stercoralis affecting 30-100 million people worldwide. Many Southeast-Asian countries report a high prevalence of S. stercoralis infection, but there are little data from Vietnam. Here, we evaluated the seroprevalence of S. stercoralis related to geography, sex and age in Vietnam through serological testing of anonymized sera. Sera (n = 1710, 1340 adults and 270 children) from an anonymized age-stratified serum bank from four regions in Vietnam between 2012 and 2013 were tested using a commercial Strongyloides ratti immunoglobulin G ELISA. Seroreactivity was found in 29·1% (390/1340) of adults and 5·5% (15/270) of children. Male adults were more frequently seroreactive than females (33·3% vs. 24·9%, P = 0·001). The rural central highlands had the highest seroprevalence (42·4% of adults). Seroreactivity in the other regions was 29·9% (Hue) and 26·0% and 18·2% in the large urban centres of Hanoi and Ho Chi Minh City, respectively. We conclude that seroprevalence of S. stercoralis was high in the Vietnamese adult population, especially in rural areas.

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

“…1b, c) who visited Hanoi Medical University Hospital, including an infection prevalence higher in the rural areas than in the urban areas (Table 2), may be considered as relatively high, although it agrees well with seroprevalence data reported previously from this country. In a study of sera selected from a serum bank, the seroprevalence showed to be highest in the rural central highlands (42.4% out of 335 adult subjects from Dak Lak), followed by the central coast area (29.9% of 335 adult subjects from Hue), and with lower prevalences in the big cities such as in Ho Chi Minh (18.2% of 335 adult subjects) and Hanoi (26.0% of 335 adult subjects) [35]. Our study of a larger number of subjects revealed that in the Hanoi capital area strongyloidiasis prevalence is somewhat lower, i.e.…”

Clinical characteristics, organ failure, inflammatory markers and prediction of mortality in patients with community acquired bloodstream infection

“…We also report the high prevalence of Enterobacteriacaea (18.1% or 13/72) as a cause of meningitis in adult BSI patients compared to previous studies from Viet Nam (13.5% or 30/222 of CSF isolates from 1996 and 2005) [ 23 ], Iceland (11.3% or 12/106 of positive CSF cultures during 1995–2010) [ 24 ] and Denmark (6.1% or 88/1437 during 1991–2000) [ 25 ]. The high prevalence of meningitis associated with Enterobacteriaceae in this setting may be related to Strongyloides hyperinfection, given the evidence for high seroprevalence of Strongyloides infection in this population [ 26 ].…”

Plans for Nationwide Serosurveillance Network in Vietnam

“…To date, 75,000 samples have been collected as part of this study, and this number continues to grow. In 2012–2013, OUCRU and NIHE collaborated to collect residual serum samples from 4 hospitals around the country; this study collected 1,300 residual samples from patients stratified by age ( 14 , 25 ). These samples have since been tested for antibodies to strongyloides (and showed high seroprevalence) ( 25 ) and to measles virus.…”

“…In 2012–2013, OUCRU and NIHE collaborated to collect residual serum samples from 4 hospitals around the country; this study collected 1,300 residual samples from patients stratified by age ( 14 , 25 ). These samples have since been tested for antibodies to strongyloides (and showed high seroprevalence) ( 25 ) and to measles virus. Work from OUCRU assessed population exposure and immunity to chikungunya virus over time at 4 locations across Vietnam ( 26 ).…”

“…For the hospital-based collection of residual serum, we envisage collecting serum, stratified by patient age, from 20–25 centers. We intend to have age-stratified collection of serum with 1-year bands for patients 1–20 years of age and 5-year bands for patients 20–70 years of age, collecting a total of 200 samples every 3 months and storing them at −20°C, as has been done in previous studies ( 14 , 25 ). This method will ensure that collection is in line with the standards of the European Sero-Epidemiology Network ( 16 ).…”