Update on the Mapping of Prevalence and Intensity of Infection for Soil-Transmitted Helminth Infections in Latin America and the Caribbean: A Call for Action

Abstract

It is estimated that in Latin America and the Caribbean (LAC) at least 13.9 million preschool age and 35.4 million school age children are at risk of infections by soil-transmitted helminths (STH): Ascaris lumbricoides, Trichuris trichiura and hookworms (Necator americanus and Ancylostoma duodenale). Although infections caused by this group of parasites are associated with chronic deleterious effects on nutrition and growth, iron and vitamin A status and cognitive development in children, few countries in the LAC Region have implemented nationwide surveys on prevalence and intensity of infection. The aim of this study was to identify gaps on the mapping of prevalence and intensity of STH infections based on data published between 2000 and 2010 in LAC, and to call for including mapping as part of action plans against these infections. A total of 335 published data points for STH prevalence were found for 18 countries (11.9% data points for preschool age children, 56.7% for school age children and 31.3% for children from 1 to 14 years of age). We found that 62.7% of data points showed prevalence levels above 20%. Data on the intensity of infection were found for seven countries. The analysis also highlights that there is still an important lack of data on prevalence and intensity of infection to determine the burden of disease based on epidemiological surveys, particularly among preschool age children. This situation is a challenge for LAC given that adequate planning of interventions such as deworming requires information on prevalence to determine the frequency of needed anthelmintic drug administration and to conduct monitoring and evaluation of progress in drug coverage.

Effects of poor hygiene on cytokine phenotypes in children in the tropics

“…We observed previously that PBLs from children with chronic geohelminth infections [2, 4], and among those higher in the birth order [4] and living in poor conditions [3] produced higher levels of SEB-induced IL-10. Geohelminths remain a common environmental exposure in Latin American countries with the majority of studies showing prevalence greater than 20 % [6]. In the present study, we show that PBLs from children with geohelminth infections and higher in the birth order produce ‘regulated’ phenotypes of cytokine profiles both homeostatically (resulting in generalized cytokine hyporesponsiveness) and upon a maximal immune stimulation (a modified Th2 response considered to represent a tolerized Th2 response).…”

A Scoping Review and Prevalence Analysis of Soil-Transmitted Helminth Infections in Honduras

“…Moreover, we reveal prevalence differentials at sub-national administrative levels, which can prove useful for establishing a historical trail of these infections, and most importantly help design better interventions for their prevention and control [60].…”

Current Status of Human Hookworm Infections, Ascariasis, Trichuriasis, Schistosomiasis Mekongi and Other Trematodiases in Lao People's Democratic Republic

“…[1][2][3] Ascaris lumbricoides is estimated to infect 1.221 billion people globally, T. trichiura 795 million, and hookworms, 740 million globally. 1 The blood fluke, Schistosoma mekongi, occurs in communities along the Mekong River in Cambodia and Lao PDR, 4 causing intestinal and hepatosplenic disease.…”