ABSTRACT
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a novel coronavirus that causes coronavirus disease 19 (COVID-19), which has infected millions of people worldwide in only a few months. A minority, but significant number, of infected individuals require hospitalization and intensive care. From the start of this new virus pandemic, it was apparent that obese and/or diabetic individuals had a bad prognosis for COVID-19 progression, strongly suggesting an association between liver disease and severe COVID-19. Because chronic liver disease (CLD) is associated with immune dysregulation and inflammation, it is unsurprising that patients with CLD may carry a greater risk of adverse outcomes following SARS-CoV-2 infection. Initial COVID-19 data have also indicated that healthy infected individuals display abnormal liver function tests, suggesting a possible direct implication of SARS-CoV-2 in liver damage. Here we show that COVID-19 affects the liver metabolism and increases the morbidity and mortality of individuals with underlying CLD.
ABSTRACT
Rattus norvegicus, the brown or Norway rat, is the most abundant mammal after humans in urban areas, where they live in close proximity to people. Among rodent-borne diseases, the reservoir role of Norway rats of zoonotic parasites in cities has practically been ignored. Considering the parasitic diseases in the One Health approach, we intended to identify and quantify the zoonotic intestinal protozoans (ZIP) in an urban population of R. norvegicus in the city of Barcelona, Spain. We studied the presence of ZIP in 100 rats trapped in parks (n = 15) as well as in the city's sewage system (n = 85) in the winter of 2016/17. The protozoans were molecularly identified by means of a multiplex PCR (AllplexTM Gastrointestinal Panel-Parasite Assay). We also investigated the presence of co-infections among the species found. Four ZIP were identified, presenting significant prevalences in sewers, specifically Blastocystis (83.5%), Giardia duodenalis (37.7%), Cryptosporidium spp. (34.1%), and Dientamoeba fragilis (14.1%). Several co-infections among the detected ZIP were also detected. The reservoir role of ZIP that Norway rats play in cities as well as the role rats may play as sentinels of zoonotic parasites affecting humans in urban areas are strongly backed up by our findings. The increasing worldwide urbanization, climate change, and the COVID-19 pandemic are factors that are producing an increase in human-rat interactions. Our results should be considered a warning to the authorities to intensify rat control and surveillance in public health interventions.