The spatial distribution of Schistosoma mansoni infection before and after chemotherapy in the Jequitinhonha Valley in Brazil.
Schistosomiasis prevalence and egg counts remained low one year after chemotherapy in most households in a hyperendemic rural area in northern Minas Gerais but several distinct spatial patterns could be observed in relation to IgE levels and to a lesser extent to exposure risk (TBM) and type of water supply. An inverse relationship between pre-treatment household prevalence and egg counts on the one hand and post-treatment IgE levels on the other were noted in two of the five communities. Low exposure risk was associated with the low pre-treatment infection rates in the central village but did not contribute to the decline of infection rates after chemotherapy in the study area, as indicated by the significant increase in water contact during the posttreatment period (p < 0.0001). Distance between households and the streams and socioeconomic factors were also unimportant in predicting the spatial distribution of infection. These results are consistent with the production and antiparasitic effect of high levels of IgE in Schistosoma mansoni infection.
Gazzinelli
Andrea
A
Escola de Enfermagem, Universidade Federal de Minas Gerais, 30130-100 Belo Horizonte, MG, Brazil. andreag@enf.ufmg.br
Hightower
Allen
A
LoVerde
Philip T
PT
Haddad
João Paulo Amaral
JP
Pereira
Wesley Rodrigues
WR
Bethony
Jeffrey
J
Correa-Oliveira
Rodrigo
R
Kloos
Helmut
H
D000293:Adolescent; D000328:Adult; D015766:Albendazole / Q000008:administration & dosage*; D000818:Animals; D000871:Anthelmintics / Q000008:administration & dosage*; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005243:Feces / Q000469:parasitology; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D010270:Parasite Egg Count; D011223:Praziquantel / Q000008:administration & dosage*; D012550:Schistosoma mansoni / Q000302:isolation & purification*; D012555:Schistosomiasis mansoni / Q000188:drug therapy* / Q000453:epidemiology / Q000276:immunology; D014867:Water / Q000469:parasitology
D000871:Anthelmintics; D014867:Water; D007073:Immunoglobulin E; D011223:Praziquantel; D015766:Albendazole