Longitudinal Evaluation of Enteric Protozoa in Haitian Children by Stool Exam and Multiplex Serologic Assay

Abstract

Abstract. Haitian children were monitored longitudinally in a filariasis study. Included were stool samples examined for Giardia intestinalis and Entamoeba histolytica cysts, and serum specimens analyzed for immunoglobulin G (IgG) responses to eight recombinant antigens from G. intestinalis (variant-specific surface protein [VSP1-VSP5]), E. histolytica (lectin adhesion molecule [LecA]), and Cryptosporidium parvum (17-and 27-kDa) using a multiplex bead assay. The IgG responses to VSP antigens peaked at 2 years of age and then diminished and were significantly lower (P 0.002) in children 4.5 years than in children 4.5 years. The IgG responses to Cryptosporidium tended to increase with age. The IgG responses to LecA and VSP antigens and the prevalence of stools positive for cysts were significantly higher (P 0.037 and P 0.035, respectively) in the rainy season than in the dry season. The multiplex bead assay provides a powerful tool for analyzing serologic responses to multiple pathogens.

Molecular diagnosis of infectious diarrhea: focus on enteric protozoa

“…Intra-and interspecies oral-fecal transmission facilitates endemicity of enteric protozoa in low-income communities of South East Asia [6,7], the Pacific Islands [8,9], Africa [7], Mexico, the Caribbean Islands [10,11] and Central and South America [12,13] -collectively termed the developing worldwhere limited access to adequate nutrition, safe drinking water, effective diagnostic tools and antimicrobial therapies facilitates persistent environmental exposure to infectious agents. In these regions, application of conventional and molecular diagnostics for protozoa are yielding critical insights into the etiology of infectious diarrhea, which is second only to respiratory diseases as a cause of mortality among children less than 5 globally [14].…”

Measuring Haitian children's exposure to chikungunya, dengue and malaria

“…Of these articles, nine described laboratory techniques based on the reverse-transcription polymerase chain reaction, two used assays based on the same reaction to identify chikungunya virus in the field 14 , 15 and one described an antibody-neutralization technique 16 . As multiplex bead assays allows the simultaneous collection of data on antibody responses to multiple antigens, 17 – 23 we investigated the use of such an assay to assess the IgG responses to antigens from chikungunya and dengue virus and Plasmodium falciparum in Haitian children. Our post-hoc testing of blood samples was primarily done to generate epidemiological data about the introduction of chikungunya virus in Haiti and was not aimed at diagnosis or case management.…”

Serological Responses to Filarial Antigens in Malian Children Attending Elementary Schools

“…11,13 The MBA is at least as sensitive as ELISA. [16][17][18] Funding for neglected tropical disease surveillance is limited.…”

“…Bound antigen-specific IgG was detected on the coupled beads as previously described. 13 Between steps, the magnetic beads were washed three times with 0.05% Tween 20 PBS, using a Bio-Plex Pro II Wash Station (Bio-Rad, Hercules, CA). Data were acquired using a Bio-Plex 100 reader with Bio-Plex Manager 6.1 software (Bio-Rad).…”