[Seroprevalence of Trypanosoma cruzi antibodies and associated risk factors among the population under 18 years of age in Veracruz, Mexico].
OBJECTIVE
To determine the prevalence of Trypanasoma cruzi antibodies among the population under 18 years of age in the state of Veracruz, Mexico, and to identify risk factors associated with housing conditions and vector presence and distribution.


METHODS
A cross-sectional, epidemiological study of the population under 18 years of age living in 10 of the 11 health districts of the state of Veracruz, Mexico, from 2000 to 2001. Presence of T. cruzi antibodies was determined by hemagglutination inhibition test (HAI) and enzyme-linked immunosorbent assays (ELISA) of serum samples spotted on filter paper, and confirmed by HAI, ELISA, and indirect immunofluorescence assay (IFA) on serum samples. A questionnaire was administered to determined housing conditions, and entomological indices for triatomines were calculated for both the intra- and peridomiciliary areas. The results were analyzed using bifactorial and multifactorial unconditional logistic regression.


RESULTS
Of the 150 individuals presenting an initial reaction, 14 were confirmed positive (5 by HAI, ELISA and IFA; 6 by HAI and ELISA, and 3 by ELISA and IFA), for a total prevalence rate of 0.91% (95% CI: 0.85-0.94). All of the confirmed-positive cases were from five of 14 health districts, with the Tuxpan district having the highest prevalence rate: 5.2% (95%CI: 1.2-9.0). Risk factors included having noticed cracks in the house walls and gaps in the roof. The only species of vector captured was Triatoma dimidiata. The entomologic indices for infestation, colonization, and natural infection were: 10.9%, 50.0%, and 9.0%, respectively.


CONCLUSIONS
Active, vector-borne transmission of T. cruzi was confirmed in the state of Veracruz, Mexico, with an overall antibody seroprevalence rate of 0.19% among the population under 18 years of age. Seroprevalence rates among this segment of the population, which serves as a sentinel group, should be closely monitored to determine if more stringent methods of vector control and epidemiological surveillance are needed.
Salazar
Paz María
PM
Universidad Nacional Autónoma de México, Facultad de Medicina, Departamento de Microbiología y Parasitología, México, D.F., México. pazmar@servidor.unam.mx
Rojas
Gloria
G
Bucio
Martha
M
Cabrera
Margarita
M
García
Guadalupe
G
Ruiz
Adela
A
Guevara
Yolanda
Y
Tapia
Roberto
R
D000293:Adolescent; D000818:Animals; D000913:Antibodies, Protozoan / Q000032:analysis*; D014355:Chagas Disease / Q000453:epidemiology* / Q000635:transmission; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006385:Hemagglutination Inhibition Tests; D006798:Housing; D006801:Humans; D007303:Insect Vectors; D016015:Logistic Models; D008297:Male; D008800:Mexico / Q000453:epidemiology; D012307:Risk Factors; D018571:Sentinel Surveillance; D016036:Seroepidemiologic Studies; D011795:Surveys and Questionnaires; D014224:Triatoma; D014349:Trypanosoma cruzi / Q000276:immunology*
D000913:Antibodies, Protozoan