It’s probably not actually a “new” bacterium but rather recognition of a species that we’ve been mixing up with something else, but regardless, a paper in the International Journal of Systematic and Evolutionary Microbiology (yes, that’s an actual journal) describes a new Staphylococcus species, Staphylococcus cornubiensis (Murray et al. 2018).
Here’s what we know:
- The bacterium was isolated from a 64-year-old man with a soft tissue infection. Only a single bacterial colony was present on the wound culture. To me, that raises questions about whether it was clinically relevant or just a contaminant or part of the normal skin microbiota.
- It’s a coagulase-positive staph. Staph can be coagulase-positive or coagulase-negative. Coagulase testing is a method that’s used to group staph, and the staph that cause the most disease (e.g. S. aureus, S. pseudintermedius) are coagulase-positive.
- Genetically, it’s a member of the Staph. intermedius group (SIG). This includes S. pseudintermedius (the species that’s the main cause of staphylococcal disease in dogs), S. intermedius (mainly found in pigeons) and S. delphini (found mainly in dolphins and mink). It’s very closely related to these species but is different enough that it might be a different species.
- It was also found during a study that went back and looked at historical SIG isolates from people.
- It’s very closely related to a Staph isolated isolated from a dog in Norway in 2008.
- Cornubiensis comes from the Latin name for Cornwall, the UK city where the infected person resided.
The close similarity to an isolate from a dog (and S. pseudintermedius) has led to a suggestion that it might have originated from a dog. Nothing is known about the patient’s dog ownership or dog contact, so it’s speculative. It’s not an unreasonable idea, but a lot more investigation needs to be done to support some of the headlines that have already sprouted as a result of this finding.
Most likely, this is a new Staph species that’s rare and of limited consequence to people or animals, and is simply one of the thousands of different bacteria that live in or on us, and our animals, all the time. I wouldn’t be surprised if it has a canine origin, but I doubt that this report means there are any new risks or new things to worry about.