Parasite contamination of soil in households of a Mexican rural community endemic for neurocysticercosis

Abstract

High neurocysticercosis (NC) prevalence was recently determined by a computed tomography (CT) scan study in the community of Tepetzitzintla, State of Puebla, Mexico. The aim of the present work was to evaluate the magnitude of fecal and parasite contamination by Taenia spp. in the soil of households of this community during the four seasons of the year. The toilet, backyard, kitchen, washboard, water containers and corrals of 14 to 26 households were sampled during each season. High Taenia spp. egg intensity was found in 24.2% of the sampled areas. The highest percentage was detected in Spring and the lowest in Summer. Significantly higher levels of Taenia spp. eggs were present in kitchen soil samples. A significant correlation was found between the presence of Taenia spp. eggs in household soil during the Summer, and NC diagnoses of the inhabitants by CT scan. Coproparasitological examinations and anti-cysticercal antibodies were determined in a cohort of inhabitants of the sampled households. Antibody levels and coproparasitological results were not associated with NC. Overall, these results illustrate the high degree of fecal contamination of potential risk to human health in rural communities and could be of use for control programmes.

Neurocysticercosis: risk and primary prevention strategies update

“…eggs in Puebla, Mexico. Soil samples (n ¼ 391) taken over four seasons from 26 houses (outhouse, backyard, kitchen, washboard area, and corral locations) showed that kitchen soils were the most heavily contaminated, that contamination persisted throughout the year, and that a statistically significant correlation between NCC and summer household soil contamination existed (Huerta et al 2008). Though an earlier study by failed to show significant Taenia spp.…”

“…household latrine), allowing pigs access to human feces (either intentionally or not), poor hygiene, lack of potable water supply, and the presence of Taenia spp. eggs in kitchen soil were associated with porcine cysticercosis, human cysticercosis (including NCC) or taeniasis Sarti-G et al 1992;Cao et al 1997;Sa´nchez et al 1998;Silva-Vergara et al 1998;Rodriquez-Canul et al 1999;Carrique-Mas et al 2001;Pouedet et al 2002;Ngowi et al 2004;Boa et al 2006;Morales et al 2006;Prasad et al 2007;Huerta et al 2008;. In two studies, one conducted in El Salvador and one in Vietnam, the use of human biosolids in agricultural applications was associated with parasite infection and, therefore, has potential significance to the incidental ingestion of T. solium eggs where present (Humphries et al 1997;Corrales et al 2006).…”

“…Recently, Huerta et al (2008) reported on the magnitude of household soil contamination with Taenia spp. eggs in Puebla, Mexico.…”

Genetic polymorphism in Taenia solium metacestodes from different Brazilian geographic areas

“…Moreover, the relevance of cysticercosis as a public health problem is highlighted by local transmission (Sorvillo et al 2011). Human cysticercosis is acquired accidentally by the ingestion of T. solium eggs and its transmission is related to a lack of sanitation, bad personal hygiene and the inadequate disposal of human faeces (Vianna et al 1986, Huerta et al 2008, Flisser & Correa 2010.…”

Clustering of Necropsy-Confirmed Porcine Cysticercosis Surrounding Taenia solium Tapeworm Carriers in Peru

“…Alternate exposure routes that have been proposed include the contamination of pig feed with T. solium eggs 25 and the persistence of low concentrations of T. solium eggs in the environment. Evidence for environmental persistence of T. solium eggs is the most developed, as eggs have been found in the soil of some endemic communities, 26 and eggs of related cestode species have been found to remain viable in moist environments for between 6 months and 4 years. [27][28][29][30] There is also evidence that T. solium eggs can be dispersed by arthropod vectors.…”