Population genomics of ancient and modern Trichuris trichiura.

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.

Prevalence and intensity of soil-transmitted helminthiasis, prevalence of malaria and nutritional status of school going children in honduras.

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.

Acción del antiveneno botrópico polivalente sobre las actividades proteolíticas presentes en los venenos de serpientes peruanas / Action of polivalent bothropic antivenom on proteolytic activities from peruvian snake venoms

Los venenos de las serpientes peruanas causantes de la mayoría de accidentes ofídicos, contienen enzimas proteolíticas que pueden degradar proteínas tisulares y plasmáticas, así como causar hipotensión y coagulación sanguínea. Objetivos. Evaluar la capacidadinhibitoria del antiveneno botrópico polivalente al estado líquido producido por el Instituto Nacional de Salud del Perú (INS) sobre las actividades caseinolítica, coagulante y amidolítica de los venenos de Bothrops atrox, Bothrops brazili, Bothrops pictus y Bothrops barnetti. Materiales y métodos. Se usaron en cada caso sustratos como caseína, fibrinógeno bovino y el cromógeno benzoil-arginil-p-nitroanilida(BApNA) respectivamente, y se midieron los cambios en los valores de la actividad enzimática a ½, 1 y 2 dosis del antiveneno tanto al estado natural como calentado a 37 °C durante cinco días. Resultados. La actividad caseinolítica es la más resistente a la inhibición especialmente por el suero no calentado en tanto que, la actividad amidolítica fue severamente inhibida principalmente en los venenosde B. pictus y B. atrox. Así mismo la actividad coagulante fue totalmente inhibida en el veneno de B. pictus, mostrándose a su vez unaelevada inhibición sobre los venenos de B. brazili y B. atrox. Para las actividades coagulante y amidolítica, los sueros calentados fueron menos efectivos que aquellos al estado natural. Conclusiones. El suero antibotrópico polivalente producido por el INS es efectivo parainhibir las actividades proteolíticas de los venenos de las serpientes peruanas ensayadas.

Peruvian snake venoms responsible for most of ophidism accidents, contain proteolytic enzymes that can degrade tissue and plasmatic proteins, as well as cause hypotension and blood coagulation. Objectives. The inhibiting capacity of liquid polyvalent bothropic antivenom produced by Instituto Nacional de Salud (INS), has been evaluated on caseinolytic, coagulant and amidolytic activities on Bothrops atrox,Bothrops brazili, Bothrops pictus and Bothrops barnetti venoms. Material and methods. Using in each case casein, bovine fibrinogen and the chromogenic substrate BApNA respectively, measuring changes in values of enzymatic activity at ½, 1 and 2 doses of either natural and heating (incubated at 37 °C during five days) antivenom. Results. Caseinolytic activity is more resistant to inhibition especially by thenatural antivenom, amidolytic activity was severely inhibited mainly in B. pictus and B. atrox venoms. Also coagulant activity was totallyinhibited in B. pictus venom, being high on B. brazili and B. atrox venoms. For coagulant and amidolytic activities, heated antivenom was less effective than natural one. Conclusions. The bothropic antivenom produced by INS is effective to inhibit the proteolytic activity from Peruvian snake venoms tested.

Características bioquímicas y evaluación preclínica de un antiveneno botrópico liofilizado contra el veneno de la serpiente Bothrops atrox / Biochemicals characteristics and pre-clinical testing of lyophilized bothropic antivenom against bothrops atrox snake venom

Se han estudiado las características bioquímicas y la capacidad neutralizante del antiveneno botrópico liofilizado producido por el Instituto Nacional de Salud (Lima, Perú), se encontró que posee 51,4 mg/mL de proteínas, las preparaciones liofilizadas se reconstituyen en un periodo de 10 min alcanzando valores de Abs600nm y pH de 0,091 y 7,0, respectivamente. Para el caso de las actividades tóxicas delveneno en estudio se obtuvieron valores de toxicidad DL50: 3,33 μg/g ratón, dosis hemorrágica mínima: 4,10 mas o menos 0,64 μg, dosis miotóxica mínima 30,2 mas o menos 2,5 μg, dosis coagulante mínima: 4,50 mas o menos 0,6 μg y dosis defibrinante mínima: 8 μg, y valores de dosis efectiva del antiveneno evaluado de 140,48 (120,09-164,33), 230,67 mas o menos11,78, 316,56 mas o menos 40,31, 105,5 mas o menos 4,2 y 500 μL antiveneno/mg veneno, respectivamente, lo cual indica que posee capacidad para neutralizar tales parámetros. Por estas razones se concluye que el producto biológico investigado cumple con los requerimientos de la Organización Mundial de la Salud (OMS) para ser considerado un antiveneno neutralizante de las principales actividades biológicas antes señaladas.

Biochemical features and neutralizing capacity of lyophilized bothropic antivenom elaborated by the Peruvian National Health Institute (Lima, Peru). It was found that the antivenom protein contents is 51.4 mg/mL. Lyophilized preparations can be reconstituted in 10 minutes, reaching Abs600nm and pH values reported as 0.091 and 7.0, respectively. Regarding toxicity of the venom for mice, LD50 was 3.33 μg,minimal hemorrhagic dose was 4.10 more or less 0.64 μg, minimal myotoxic dose was 30.2 more or less 2.5 μg, minimal coagulant dose was 4.50 more or less 0.6 μg, and the minimal defibrinating dose was 8 μg; and the effective dose values of the antivenom for the aforementioned parameters were140.48 (120.09-164.33), 230.67 more or less 11.78, 316.56 more or less 40.31, 105.5 more or less 4.2, and 500 μL antivenom/mg venom, respectively, indicating that this preparation has the ability to neutralize each of the parameters tested. For these reasons we conclude that the investigated product complies with the World Health Organization (WHO) requirements to be considered an effective antivenom capable of neutralizing themain biological activities previously mentioned.