Seroepidemiology of leptospirosis in southern Vietnamese children.
OBJECTIVE
To estimate the seroprevalence of human leptospirosis in southern Vietnam.


METHODS
All pupils (n=961) of two primary schools in two communes in southern Vietnam were screened for the presence of serum Leptospira immunoglobulin (Ig)G. Leptospira IgM was tested in 92 randomly selected samples. IgM and IgG were tested with a commercially available enzyme-linked immunosorbent assay (ELISA).


RESULTS
Leptospira IgG was found in 123 (12.8%, 95% CI: 10.8-15.1) children with a male:female ratio of 1.5:1. At the age of 7 years the prevalence was 11%. Log-linear binary regression of the IgG seroprevalence by age showed a mean seroconversion rate of 1.5% (95% CI: 1.23-1.75) per year. Five (5.4%, 95% CI: 2.3-12.1) samples were definitely positive for IgM. Presence of serum Leptospira IgG antibodies was significantly associated with swimming in rivers (RR: 1.745, 95% CI: 1.117-2.724) and wading through water (RR 1.793, 95% CI: 1.181-2.722).


CONCLUSIONS
Our data emphasize the importance of leptospirosis among children in Vietnam, despite the absence of severe disease, and stress the need for adequate and cheap diagnostics.
Thai
Khoa T D
KT
Division of Infectious Diseases, Tropical Medicine & AIDS, Academic Medical Center, Amsterdam, the Netherlands, and Tropical Diseases Clinical Research Center, Cho Ray Hospital, Ho Chi Minh City, Vietnam.
Binh
Tran Quang
TQ
Giao
Phan Trong
PT
Phuong
Hoang Lan
HL
Hung
Le Quoc
le Q
Van Nam
Nguyen
N
Nga
Tran Thanh
TT
Goris
Marga G A
MG
de Vries
Peter J
PJ
D000293:Adolescent; D017677:Age Distribution; D000907:Antibodies, Bacterial / Q000097:blood; D002648:Child; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D015994:Incidence; D007919:Leptospira / Q000276:immunology; D007922:Leptospirosis / Q000097:blood / Q000453:epidemiology* / Q000276:immunology; D008297:Male; D011159:Population Surveillance / Q000379:methods; D015995:Prevalence; D012307:Risk Factors; D045483:Rivers / Q000382:microbiology; D016036:Seroepidemiologic Studies; D017678:Sex Distribution; D013550:Swimming; D014744:Vietnam / Q000453:epidemiology; D014871:Water Microbiology
D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D007075:Immunoglobulin M