Occurrence, risk factors and genotypes ofEnterocytozoon bieneusiin dogs and cats in Guangzhou, southern China: high genotype diversity and zoonotic concern

Abstract

Background Enterocytozoon bieneusi, a common opportunistic fungal pathogen, has a wide range of hosts. Limited epidemiological data onE. bieneusiintestinal infections in companion animals (dogs and cats) in China exists. In this study, fecal samples (651 from dogs and 389 from cats) in Guangzhou city, Guangdong Province, China, were collected, and the ribosomal internal transcribed (ITS) spacer region from the DNA extracted from them was Polymerase Chain Reaction (PCR)-amplified and sequenced. Results Based on the sequencing data,E. bieneusiwas identified in the fecal samples collected from 149 (22.9%) and 79 (20.3%) dogs and cats. Of the factors investigated, poor living conditions appeared to be the major risk factor for contracting the pathogen. ElevenE. bieneusigenotypes, six known (PtEb IX, GD1, D, CD9, EbpC, I) and five novel (designated here as GD2- GD6), were found in dogs. Eight genotypes, six known (PtEb IX, GD1, D, CD9, EbpC, Type IV) and two novel (GD2 and GC1), were identified in cats. Genotype PtEb IX was most common in both dogs and cats, followed by genotype GD1. Conclusions Although PtEb IX was the most commonE. bieneusigenotype in dogs, this is the first report of this genotype dominating in cats. The same genotype distribution of the pathogen between the two different companion animals species in the same geographic area indicates that inter-species transmission is probable. The widespread existence of zoonoticE. bieneusigenotypes (D, EbpC, Type IV) in companion animals indicates that they are potential sources of environmental contamination and infections in humans.