Longitudinal study on methicillin-resistant Staphylococcus pseudintermedius in households

Area of Science:

• Veterinary Microbiology
• Zoonotic Disease Research
• One Health Studies

Background:

• Methicillin-resistant Staphylococcus pseudintermedius (MRSP) is an emerging canine pathogen with limited longitudinal data on its dynamics.
• Previous studies focused on prevalence, leaving gaps in understanding MRSP transmission within households and environments.

Purpose of the Study:

• To investigate the longitudinal dynamics of MRSP colonization in dogs.
• To assess MRSP transmission between index dogs, contact animals, humans, and the environment over six months.

Main Methods:

• A longitudinal study involving 16 dogs with recent MRSP infections.
• Monthly sampling of dogs, contact animals, owners, and household environments for six months.
• Bacteriological culture and genotyping of MRSP isolates.

Main Results:

• Index dogs remained colonized with MRSP for extended periods, up to six months in some cases.
• MRSP was detected in contact animals and environments, often concurrently with positive index dogs.
• MRSP survived in environments for prolonged durations, even without positive animal or human cases.
• Genotyping confirmed isolate similarity within households, with exceptions indicating potential multiple introductions or distinct strains.

Conclusions:

• MRSP can establish prolonged colonization in dogs, necessitating continued vigilance by veterinarians.
• Significant risk of MRSP transmission to close contact animals exists.
• Humans appear to be minor reservoirs, with rare and transient MRSP positivity observed.