Introduction

Infectious conjunctivitis is commonly observed in cats in shelters and is often associated with upper respiratory disease. Feline herpesvirus 1 and Chlamydia felis are proposed to be the major primary pathogens in this syndrome. Mycoplasma spp. are commonly isolated from the upper respiratory tract of healthy cats; however, several studies have found an increased prevalence of Mycoplasma spp. in cats with URTD, but a study has not been performed to evaluate this in Brazil.

Objectives

To use a PCR assay to determine the prevalence of Mycoplasma spp. DNA in samples collected from the conjunctival fornix from stray cats with and without conjunctivitis and URTD symptoms in São Paulo, Brazil. Genome sequencing was used to identify the Mycoplasma species.

Results

A total of 215 cats were assayed; of these, 153 (71%) were clinically ill and 62 (29%) did not show clinical signs for URTD. A quantitative 4-point scale from 1 to 4 (least to most severe) was used to score URTD; conjunctivitis was observed in 55 cats. The overall prevalence rate for Mycoplasma spp. was 29.8% (64). DNA of M. felis, M. gateae, and M. canadense were amplified from either normal or diseased cats (Table 1). DNA of M. cynos was amplified from one normal cat. Cats with conjunctivitis were more likely to be positive for M. felis than normal cats (p=0.0064; Fisher's exact test).

Table 1. Species of Mycoplasma and clinical findings

Conclusions and Relevance

Mycoplasma spp. are common amongst cats housed in shelters in Brazil, and M. felis appears to be associated with conjunctivitis.