ABSTRACT
Stool microscopy and an enzyme-linked immunosorbent assay (ELISA) for Giardia lamblia antigen detection were compared for detecting G. lamblia in 30 Peruvian infants. Of 1,131 fecal specimens, G. lamblia was detected by ELISA alone in 44, by microscopy alone in 17, and by both methods in 91. In another group of 17 children negative for G. lamblia by stool microscopy, 6 had G. lamblia detected by ELISA or duodenal aspiration: 2 only by ELISA, 1 only by duodenal aspirate examination, and 3 by both examinations. The ELISA is useful for the detection of G. lamblia in fecal specimens but compared to stool microscopy does not significantly increase the detection of cases.
Subject(s)
Antigens, Protozoan/isolation & purification , Giardia/immunology , Giardiasis/diagnosis , Animals , Duodenum/immunology , Duodenum/parasitology , Enzyme-Linked Immunosorbent Assay , Evaluation Studies as Topic , Feces/parasitology , Giardia/isolation & purification , Giardiasis/immunology , Giardiasis/parasitology , Humans , Infant , Infant, Newborn , Peru , Sensitivity and SpecificityABSTRACT
An enzyme-linked immunosorbent assay was used to examine randomly selected sera from 389 children and adults in Lima, Peru, and 84 children in Maracaibo and Caracas, Venezuela, for IgM or IgG antibody to Cryptosporidium. In Peru and Venezuela, 19.8% and 15.5% of the study populations, respectively, were positive for both specific IgG and IgM antibodies, a result consistent with active or recent infection and representing a larger percentage than normally reported from stool examinations of individuals seeking medical attention. Sixty-four percent of subjects from each country had detectable levels of specific IgG, indicating infection sometime in life. Detection of specific IgG increased in the two- to three-year-old age-group, a result suggesting that this is a common age for infection. Persistence of IgG and, less often, IgM antibody response over 12 mo occurred in some subjects, although the significance of this finding is uncertain. Our findings suggest that Cryptosporidium infections are endemic in the communities surveyed and that most residents have been infected.
Subject(s)
Antibodies, Protozoan/analysis , Coccidia/immunology , Cryptosporidiosis/epidemiology , Cryptosporidium/immunology , Adolescent , Adult , Animals , Child , Child, Preschool , Enzyme-Linked Immunosorbent Assay , Humans , Immunoglobulin G/analysis , Immunoglobulin M/analysis , Infant , Infant, Newborn , Peru , VenezuelaABSTRACT
Three hundred thirty-nine migrant worker women and children were screened by single stool examination for intestinal parasites. Infection occurred in 34.2%. Giardia lamblia and Trichuris trichiura were the most common pathogens; Entamoeba coli and Endolimax nana were the most common commensals. Infants under 1 year of age were free of infection. Children between 2 and 5 years old and women between 25 and 35 years old had the highest prevalence. Significantly more Haitians were infected than Mexican-Americans or American blacks. Of ten symptoms, only abdominal pain and gas correlated significantly with infection. This migrant population has a greater prevalence of intestinal parasites than the general American public. Screening by stool examination may be beneficial to diminish the reservoir of infection.