Molecular epidemiology of Streptococcus zooepidemicus isolated from the respiratory tracts of Thoroughbred racehorses in training.
The objective of this study was to characterise the molecular epidemiology of Streptococcus zooepidemicus isolated from the respiratory tracts of 198 Thoroughbred racehorses based at three Newmarket training yards over a 10 month period. Typing utilised two separate PCR procedures targeting the M-like protein hypervariable and the 16S-23S RNA gene intergenic spacer regions of the bacterium. S. zooepidemicus, isolated from 23% (224/983) of study samples, comprised 24 different types of varying prevalence. The four most common types, A1HV4, A1HV2, C1HVu and D1HV1, accounted for 45% of all the typed isolates. Overall, the findings were similar to those reported in a study of Welsh Mountain ponies and confirm that in equids, S. zooepidemicus is not a homogeneous, clonal population but instead represents a wide diversity of strain types. This diversity also highlights potential difficulties in using vaccines to control S. zooepidemicus infections in horses as it is likely that the induction of a heterologous, cross-protective immunity will be required.
Barquero
Nuria
N
Equine Epidemiology and Disease Surveillance, Centre for Preventive Medicine, Animal Health Trust, Newmarket, Suffolk CB8 7UU, UK.
Chanter
Neil
N
Laxton
Ross
R
Wood
James L N
JL
Newton
J Richard
JR
D000818:Animals; D015373:Bacterial Typing Techniques; D004269:DNA, Bacterial / Q000032:analysis; D006734:Horse Diseases / Q000453:epidemiology* / Q000382:microbiology*; D006736:Horses; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012141:Respiratory Tract Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D012621:Seasons; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D018502:Streptococcus equi / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D006113:United Kingdom / Q000453:epidemiology
D004269:DNA, Bacterial