Use of faecal parasite concentrator “mini Parasep SF” for detecting microsporidia in urban areas.

Abstract

Microsporidia are recognised as an emerging opportunistic group of pathogens. Recent studies highlight the possible zoonotic potential of various microsporidia species but transmission routes in humans and animals are still difficult to evaluate. There is increasing evidence indicating that urban animals may play a significant role in the spread of microsporidia but little is known about their presence in the urban environment. The aim of this study was twofold: a) to determine the presence of human-associated microsporidia in animal faecal samples in urban parks in Leicester (UK); b) to investigate the potential use of the faecal parasite concentrator mini Parasep SF (Apacor, UK) in environmental studies and the efficacy of two new formalin-free fixatives (with and without Triton X-100). 40 faecal samples were collected from Watermead Country Park (LE7 8PF) and Bradgate Park (LE6 0HE) in June 2016. A duplicate of each sample was collected to test the different fixatives. A veterinarian identified the following animal species through visual analysis of each sample: 8 avian (2 waterfowl, 2 pigeon/songbird, 4 avian species unidentified), 10 dog, 3 fox, 8 deer, 11 species unidentified due to diarrhoea. Smears were stained using a Weber’s modified trichrome stain following previous methodologies. The microscopic analysis of each smear provided the following results: 27.5% of the samples collected were found to be either positive or compatible with microsporidia structures. Positive samples for microsporidia included dog (7.5%), fox (2.5%), deer (5%), avian (waterfowl species, 2.5%) and unidentified species (10%). The same results were found in each duplicate so the different fixative solution did not affect the detection of microsporidia. These faecal concentrators may be an appropriate way to collect hazardous samples avoiding the environmental and health risks related with formalin (traditionally used in faecal concentrators). Although our results should be considered as preliminary, this study would highlight that urban animals in Leicester may be carriers of microsporidia presenting a risk for human health that should be tackled to prevent future infections.