Surveillance of SARS-CoV-2, rotavirus, norovirus genogroup II, and human adenovirus in wastewater as an epidemiological tool to anticipate outbreaks of COVID-19 and acute gastroenteritis in a city without a wastewater treatment plant in the Peruvian Highlands.

The coronavirus disease 2019 (COVID-19) pandemic has demonstrated that Wastewater Based Epidemiology is a fast and economical alternative for monitoring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the community level in high-income countries. In the present study, wastewater from a city in the Peruvian Highlands, which lacks a wastewater treatment plant, was monitored for one year to assess the relationship between the concentration of SARS-CoV-2 and the reported cases of COVID-19 in the community. Additionally, we compared the relationship between rotavirus (RV), norovirus genogroup II (NoV GGII), and human adenovirus (HAdV) with the number of reported cases of acute gastroenteritis. Before commencing the analysis of the samples, the viral recovery efficacy of three processing methods was determined in spiked wastewater with SARS-CoV-2. This evaluation demonstrated the highest recovery rate with direct analysis (72.2 %), as compared to ultrafiltration (50.8 %) and skimmed milk flocculation (5.6 %). Wastewater monitoring revealed that 72 % (36/50) of the samples tested positive for SARS-CoV-2, with direct analysis yielding the highest detection frequency and quantification of SARS-CoV-2. Furthermore, a strong correlation was observed between the concentration of SARS-CoV-2 in wastewater and the reported cases of COVID-19, mainly when we shift the concentration of SARS-CoV-2 by two weeks, which allows us to anticipate the onset of the fourth and fifth waves of the pandemic in Peru up to two weeks in advance. All samples processed using the skimmed milk flocculation method tested positive and showed high concentrations of RV, NoV GGII, and HAdV. In fact, the highest RV concentrations were detected up to four weeks before outbreaks of acute gastroenteritis reported in children under four years of age. In conclusion, the results of this study suggest that periodic wastewater monitoring is an excellent epidemiological tool for surveillance and can anticipate outbreaks of infectious diseases, such as COVID-19, in low- and middle-income countries.

Hymenolepis microstoma (Cestoda: Hymenolepididae) en ratones caseros ( Mus musculus ) de Lima, Perú / Hymenolepis microstoma (Cestoda: Hymenolepididae) in house mice (Mus musculus) from Lima, Peru

Un total de 12 cestodos adultos se colectaron de los conductos biliares de ratones domésticos (Mus musculus) provenientes de Lima, Perú. Diversas características del escólex y proglotis maduros del cestodo fueron observadas para la identificación morfológica. Así mismo, se realizó un diagnóstico molecular mediante un PCR y secuenciación parcial del gen mitocondrial citocromo c oxidasa subunidad 1 (cox1). Todos los cestodos fueron identificados como Hymenolepis microstoma por morfología y métodos moleculares. El aislado de H. microstoma de Perú mostró una similitud de secuencia significativa (> 99%) con los aislados de H. microstoma previamente reportados. Nuestro informe confirma la presencia del parásito en ratones de Lima.

A total of 12 adult cestodes were collected from the bile ducts of domestic mice (Mus musculus) from Lima, Peru. Various features of the scolex and mature proglottids of the tapeworms were observed for morphological identification. A molecular diagnosis was performed by PCR-based partial sequencing of mitochondrial gene of cytochrome c oxidase subunit 1 (cox1). All cestodes were identified as Hymenolepis microstoma by morphology and molecular methods. The H. microstoma isolate from Peru showed significant sequence similarity with previously reported isolates of H. microstoma (>99%). Our report confirms the presence of the parasite in mice from Lima.