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The neglected tropical disease trichuriasis is caused by the whipworm Trichuris trichiura, a soil-transmitted helminth that has infected humans for millennia. Today, T. trichiura infects as many as 500 million people, predominantly in communities with poor sanitary infrastructure enabling sustained faecal-oral transmission. Using whole-genome sequencing of geographically distributed worms collected from human and other primate hosts, together with ancient samples preserved in archaeologically-defined latrines and deposits dated up to one thousand years old, we present the first population genomics study of T. trichiura. We describe the continent-scale genetic structure between whipworms infecting humans and baboons relative to those infecting other primates. Admixture and population demographic analyses support a stepwise distribution of genetic variation that is highest in Uganda, consistent with an African origin and subsequent translocation with human migration. Finally, genome-wide analyses between human samples and between human and non-human primate samples reveal local regions of genetic differentiation between geographically distinct populations. These data provide insight into zoonotic reservoirs of human-infective T. trichiura and will support future efforts toward the implementation of genomic epidemiology of this globally important helminth.

The neglected tropical disease trichuriasis is caused by the whipwormTrichuris trichiura, a soil-transmitted helminth that has infected humans for millennia. Today,T. trichiurainfects as many as 500 million people, predominantly in communities with poor sanitary infrastructure enabling sustained faecal-oral transmission. Using whole-genome sequencing of geographically distributed worms collected from human and other primate hosts, together with ancient samples preserved in archaeologically-defined latrines and deposits dated up to one thousand years old, we present the first population genomics study ofT. trichiura. We describe the continent-scale genetic structure between whipworms infecting humans and baboons relative to those infecting other primates. Admixture and population demographic analyses support a stepwise distribution of genetic variation that is highest in Uganda, consistent with an African origin and subsequent translocation with human migration. Finally, genome-wide analyses between human samples and between human and non-human primate samples reveal local regions of genetic differentiation between geographically distinct populations. These data provide insight into zoonotic reservoirs of human-infectiveT. trichiuraand will support future efforts toward the implementation of genomic epidemiology of this globally important helminth.

La MEIZ inició coyunturalmente a partir de un financiamiento que un grupo de profesoras de la UNAH y una colega honduro-canadiense, gestionaron ante el Gobierno de Canadá. Estas valientes mujeres tuvieron un sueño, que parecía quijotesco en aquel momento en que la Reforma universitaria era apenas una promesa difusa, y la convulsión socio-política del país daba lugar a todo menos a la creatividad. A pesar de los obstáculos internos y externos, el Postgrado fue creado y aprobado, pero con una mística de trabajo nueva, inspirada en la Universidad de Brock, y el resto de las Universidades canadienses. Era necesario adoptar paradigmas en los que ninguno de nosotros habíamos sido formados. Requería una transformación de la mente de los coordinadores, los profesores y los asesores, para luego intentar permear en la de los estudiantes.

Background Many small studies have been done in Honduras estimating soil-transmitted helminthiasis (STH) prevalence but a country-wide study was last done in 2005. The country has the highest burden of malaria among all Central American countries. The present study was done to estimate country-wide STH prevalence and intensity, malaria prevalence and nutritional status in school going children. Methods and Findings A cross-sectional study was conducted following PAHO/WHO guidelines to select a sample of school going children of 3rd to 5th grades, representative of ecological regions in the country. A survey questionnaire was filled; anthropometric measurements, stool sample for STH and blood sample for malaria were taken. Kato-Katz method was used for STH prevalence and intensity and rapid diagnostic tests, microscopy, and polymerase chain reaction (PCR) were used for malaria parasite detection. A total of 2554 students were studied of which 43.5% had one or more STH. Trichuriasis was the most prevalent (34%) followed by ascariasis (22.3%) and hookworm (0.9%). Ecological regions II (59.7%) and VI (55.6%) in the north had the highest STH prevalence rates while IV had the lowest (10.6%). Prevalence of one or more high intensity STH was low (1.6%). Plasmodium vivax was detected by PCR in only 5 students (0.2%), all of which belonged to the same municipality; no P. falciparum infection was detected. The majority of children (83%) had normal body mass index for their respective age but a significant proportion were overweight (10.42%) and obese (4.35%). Conclusions Biannual deworming campaigns would be necessary in ecological regions II and VI, where STH prevalence is >50%. High prevalence of obesity in school going children is a worrying trend and portends of future increase in obesity related diseases. Malaria prevalence, both symptomatic and asymptomatic, was low and provides evidence for Honduras to embark on elimination of the disease., Author Summary Soil-transmitted helminthiasis (STH) are one of the most important neglected infectious diseases (NID). These not only have the potential to affect the growth and development of children, but can have irreversible consequences that carry into adulthood. However its prevalence has not been estimated since many years in Honduras. Although Honduras is the country with the highest burden of malaria in Central America, efforts to reduce the number of cases due to Plasmodium falciparum have lead the country towards an initiative for elimination. Using common platforms to do mapping of NID allows countries to reduce costs, build local capacities and strengthen monitoring and evaluation systems to track progress towards control and elimination goals. Honduras, one of the poorest countries in Central America, took advantage of an initiative to establish the prevalence of STH in school age children to assess the prevalence of malaria as a step in compiling evidence to support a future process of elimination of the disease. This innovative manner to put together epidemiological information for several NID might be replicated in other countries in the Americas to produce baseline and follow-up data to support decision making for processes to reach the goals established for these diseases.