Strongyloides stercoralis affects 30-100 million people worldwide. The burden is underestimated because of the paucity of studies, limited geographical areas surveyed, and poor quality of diagnostic tests. This study aimed at determining the epidemiology of strongyloidiasis using sensitive microscopy testing in rural populations living at different altitudes in Cusco, Peru. Data were collected from subjects aged > 3 years living in Quellouno (elevation 2,600 ft) and Limatambo (elevation 8,379 ft) districts. Subjects provided one fresh stool sample and answer a standardized questionnaire. Fresh stool was tested on site using the Baermann's test and agar plate culture. Formalin-preserved stool was tested by rapid sedimentation. Eighty percent (585/715) of eligible subjects consented to participate; after excluding subjects with missing data, 65% (462/715) were included. Fifty-five percentage were female; the median age was 33 years (interquartile range 13-52), and 72% had government health insurance. Half had intestinal parasites, and Strongyloides was the most common (24.5%) followed by Giardia (15.5%), Blastocystis (14.9%), and hookworm (11.5%). The agar plate culture detected more cases of Strongyloides than Baermann's or sedimentation tests. Strongyloides infection was more common at low altitude (26.4%) than at high altitude (18.6%), but the difference was not statistically significant (P = 0.08). Older age, walking barefoot, bathing in rivers/streams, and using municipal sewage were associated with strongyloidiasis. Strongyloides was the most prevalent parasite in the areas studied and was associated with demographic, socioeconomic, and sanitary factors.

Triclabendazole (TCBZ) resistance is an emerging problem in fascioliasis that is not well understood. Studies including small numbers of parasites fail to capture the complexity of susceptibility variations between and within Fasciolahepatica populations. As the first step to studying the complex resistant phenotype–genotype associations, we characterized a large sample of adult F. hepatica with diverging TCBZ susceptibility. We collected parasites from naturally infected livestock slaughtered in the Cusco and Cajamarca regions of Peru. These parasites were exposed to TCBZ sulfoxide (TCBZ.SO) in vitro to determine their susceptibility. We used a motility score to determine the parasite’s viability. We titrated drug concentrations and times to detect 20% non-viable (susceptible conditions) or 80% non-viable (resistant conditions) parasites. We exposed 3348 fully motile parasites to susceptible (n = 1565) or resistant (n = 1783) conditions. Three hundred and forty-one (21.8%) were classified as susceptible and 462 (25.9%) were classified as resistant. More resistant parasites were found in Cusco than in Cajamarca (p < 0.001). Resistant parasites varied by slaughterhouse (p < 0.001), month of the year (p = 0.008), fluke length (p = 0.016), and year of collection (p < 0.001). The in vitro susceptibility to TCBZ.SO in wildtype F. hepatica was associated with geography, season, and morphometry.

La pandemia del síndrome respiratorio agudo conocido como COVID-19 y causada por el virus SARS-CoV-2, ha obligado a diversos laboratorios alrededor del mundo a rediseñar y reforzar sus programas de bioseguridad con la finalidad de facilitar el diagnóstico de la enfermedad y colaborar con datos epidemiológicos para la toma de decisiones asociadas a mitigación y control. Una combinación de buenas prácticas de laboratorio y procedimientos claramente definidos, apoyados en la adecuación de la infraestructura, son necesarios para proteger al personal de laboratorio y asegurar la reproducibilidad de los resultados generados. En esta revisión se muestran los lineamientos de bioseguridad fundamentales a implementar en los laboratorios de diagnóstico de la COVID-19, basados en RT-qPCR. El establecimiento del nivel de seguridad biológica a adoptar, así como de los procedimientos operativos estándar, dependerán de la evaluación de riesgo derivada de las actividades intrínsecas del laboratorio. Hasta la fecha, la OMS ha recomendado un nivel 2 de seguridad biológica NBS-2 (BSL-2), con medidas intensificadas de nivel 3 NBS-3 (BSL-3), para actividades de diagnóstico, con prácticas y equipos de protección personal que minimicen la generación de aerosoles y reduzcan la probabilidad de infecciones adquiridas en laboratorio. De igual forma, se ha hecho énfasis en un flujo de trabajo que tome en cuenta el transporte de la muestra bajo reglamentos internacionales y procedimientos para la inactivación del virus, compatibles con la prueba diagnóstica o con los protocolos para la descontaminación de superficies. A pesar del reto que conlleva la adecuación de programas de mitigación ante un patógeno relativamente desconocido como el SARS-CoV-2, es importante destacar que la cultura de bioseguridad permite reducir los riesgos del personal y del medio ambiente y asegurar la calidad de los resultados generados, que permitan contribuir significativamente a lograr el control de la enfermedad.