title: Molecular Epidemiology ofGiardia, BlastocystisandCryptosporidiumamong Indigenous Children from the Colombian Amazon Basin.
abstract: The incidence and prevalence of intestinal parasites in children is most likely due to lack of natural or acquired resistance and differences in behavior and habits closely related to environmental and socioeconomic determinants. The most important protozoa that parasitize humans areGiardia, Entamoeba, Blastocystis, andCryptosporidium. These parasites present wide intraspecific genetic diversity and subsequently classified into assemblages and subtypes. The Amazon basin is the largest in the world and is the fifth freshwater reserve on the planet. Contradictorily, people living in these areas (Indigenous populations) have poor quality of life, which favors the infection of diseases of fecal-oral transmission. The aim of this work was to unravel the molecular epidemiology ofGiardia, BlastocystisandCryptosporidiumacross four communities (Puerto Nariño, San Juan del Soco, Villa Andrea and Nuevo Paraíso). We obtained 284 fecal samples from children under 15 years old that were analyzed by direct microscopy (261 samples) and Real Time PCR (qPCR) (284 samples). The positive samples for these protozoa were further characterized by several molecular markers to depict assemblages and subtypes. We observed a frequency ofGiardiainfection by microscopy of 23.7% (62 samples) and by qPCR of 64.8% (184 samples); forBlastocystisby microscopy of 35.2% (92 samples) and by qPCR of 88.7% (252 samples) and forCryptosporidiumonly 1.9% (5 samples) were positive by microscopy and qPCR 1.8% (5 samples). Regarding theGiardiaassemblages, using the glutamate dehydrogenase (gdh)marker we observed AI, BIII and BIV assemblages and when using triose phosphate isomerase (tpi) we observed assemblages AI, AII, BIII and BIV. In contrast,BlastocystisSTs detected were 1, 2, 3, 4, and 6. Lastly, the speciesC. viatorum, C. hominis(with the subtypes IdA19 and IaA12R8) andC. parvum(with the subtype IIcA5G3c) were identified. We observed a high profile of zoonotic transmission regarding theGiardiaassemblages andBlastocystisSTs/alleles. Also, we highlight the elevated frequency of infection by these two protozoans suggesting an active transmission in the area. Our findings reinforces the need to deploy better epidemiological surveillance systems for enteric pathogens in the area.
authors.affiliation: Facultad de Medicina, Departamento de Salud Pública, Universidad Nacional de ColombiaBogotá, Colombia; Grupo de Investigaciones Microbiológicas-UR, Programa de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del RosarioBogotá, Colombia.
authors.forename: Angie
authors.initials: A
authors.lastname: Sánchez
authors.affiliation: Grupo de Investigaciones Microbiológicas-UR, Programa de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario Bogotá, Colombia.
authors.forename: Marina
authors.initials: M
authors.lastname: Munoz
authors.affiliation: Facultad de Medicina, Departamento de Salud Pública, Universidad Nacional de Colombia Bogotá, Colombia.
authors.forename: Natalia
authors.initials: N
authors.lastname: Gómez
authors.affiliation: Facultad de Medicina, Departamento de Salud Pública, Universidad Nacional de Colombia Bogotá, Colombia.
authors.forename: Juan
authors.initials: J
authors.lastname: Tabares
authors.affiliation: Facultad de Medicina, Departamento de Salud Pública, Universidad Nacional de Colombia Bogotá, Colombia.
authors.forename: Laura
authors.initials: L
authors.lastname: Segura
authors.affiliation: Facultad de Medicina, Departamento de Salud Pública, Universidad Nacional de Colombia Bogotá, Colombia.
authors.forename: Ángela
authors.initials: Á
authors.lastname: Salazar
authors.affiliation: Facultad de Medicina, Departamento de Salud Pública, Universidad Nacional de Colombia Bogotá, Colombia.
authors.forename: Cristian
authors.initials: C
authors.lastname: Restrepo
authors.affiliation: Facultad de Medicina, Departamento de Salud Pública, Universidad Nacional de Colombia Bogotá, Colombia.
authors.forename: Miguel
authors.initials: M
authors.lastname: Ruíz
authors.affiliation: Facultad de Medicina, Departamento de Salud Pública, Universidad Nacional de Colombia Bogotá, Colombia.
authors.forename: Patricia
authors.initials: P
authors.lastname: Reyes
authors.affiliation: Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention Atlanta, GA, USA.
authors.forename: Yuchen
authors.initials: Y
authors.lastname: Qian
authors.affiliation: Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention Atlanta, GA, USA.
authors.forename: Lihua
authors.initials: L
authors.lastname: Xiao
authors.affiliation: Facultad de Medicina, Departamento de Salud Pública, Universidad Nacional de Colombia Bogotá, Colombia.
authors.forename: Myriam C
authors.initials: MC
authors.lastname: López
authors.affiliation: Grupo de Investigaciones Microbiológicas-UR, Programa de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario Bogotá, Colombia.
authors.forename: Juan D
authors.initials: JD
authors.lastname: Ramírez
keywords: Blastocystis; Cryptosporidium; Giardia; assemblages; molecular epidemiology; subtypes