Outbreak of Streptococcus equi subsp. zooepidemicus infections in cats

Abstract

Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) is a commensal of the mucous membranes and skin of animals, notably equine, and is associated with various infections in animals and humans. Here, we describe an outbreak of respiratory disease in a cattery, which, to the best of our knowledge, is the first report of S. zooepidemicus infection in cats. Clinical disease was characterized firstly by abundant purulent nasal discharges and cough, progressing to sinusitis, dyspnea, symptoms of pneumonia and death. Pathological examination revealed different degrees of inflammation of the lower respiratory tract. S. zooepidemicus was the main bacteria isolated. Sequencing of the V2 fragment of the 16S gene revealed that the isolates were distributed in two previously described genogroups.

Fig. 1

Phylogenetic tree of 22 feline S. zooepidemicus isolates and reference strains. The optimal tree was inferred by using the neighbor-joining method. The percentage of successful bootstrap replicates (n = 1000) is indicated at nodes. Evolutionary distances were computed with the Kimura 2-parameter method. Branch lengths’ are proportional to the number of nucleotide changes. Scale bar shows number of base substitution per site. Ct corresponds to feline isolates, Hs corresponds to equine ones. Ct 13/07 is a S. canis isolate. Genbank accession numbers of reference strains: S. zooepidemicus Bd 147/04 (ef406029), S. equi subsp. equi (ef 406086), S. zooepidemicus ATCC43079 (ef406034), S. zooepidemicus Bd 2/04 (ef406027), S. zooepidemicus Bd 16498/05 (ef406030), S. zooepidemicus Bd 23752/03 (ef406026), S. zooepidemicus Bd 15630/02 (ef406013), S. zooepidemicus Bd 1976/03 (ef406020), S. zooepidemicus Bd 1902/03 (ef406019), S. zooepidemicus Bd 707/03 (ef406017), S. equi subsp. ruminatorum CCUG 47520 (ef406035), S. zooepidemicus Bd 81/04 (ef406028), and out group S. dysgalactiae (ab002492), S. canis ATCC 43498 DSM 201715 (ab002483).