Colonization of Dogs and Their Owners with and in Households, Veterinary Practices, and Healthcare Facilities.

There are uncertainties with respect to the transmission of methicillin-susceptible and methicillin-resistant (MSSA and MRSA) and between dogs and humans. In this study, we investigated concomitant nasal colonization of dogs and humans in three cohorts. Cohort I, households owning dogs: In 42 of 84 households, 66 humans (36.9%) and 10 dogs (8.9%) carried . MRSA, attributed to sequence type (ST) 22 and ST130, were detected in two (1.1%) of the humans but in none of the dogs. Typing by means of -typing and whole-genome sequencing (WGS) indicated eight transmissions of between humans and dogs in 8 of 42 (19.0%) households with human carriers, whereas in 11 of 38 (29.0%) households with ≥two persons and colonization of humans, 15 human-to-human transmissions were observed ( = 0.43). was isolated from 42 dogs (37.5%), but from only one human (0.6%). In this case, WGS-based typing indicated strong relatedness of this isolate with a canine isolate from the same household. Cohort II, dogs and their owners visiting a veterinary practice: Among 17 humans and 17 dogs attending a veterinary practice, MSSA was detected in three humans and two dogs, and in only six dogs. Cohort III, dogs used for animal-assisted interventions in human healthcare facilities and their owners: MSSA was obtained in 1 of 59 dogs (1.7%) and in 17 of 60 (28.3%) of the dog owners, while was isolated from seven (12%) dogs and one (1.7%) human owner. We conclude that the risk of exchanging /MRSA between humans and dogs is higher than that for .