The credit (or blame) for the alliteration goes to colleague and frequent blog material supplier Dr. Stephen Page. It relates to an article in the prestigious medical journal Lancet (Kagihara et al. 2014) entitled “A fatal pasteurella empyema.”

The article describes the case of a 60-year-old man from Honolulu who was admitted to hospital in cardiac arrest. He had various health problems and had had a cough and body aches over the past four weeks, then suddenly deteriorated. He was resuscitated and fluid was found in his chest cavity. When they collected a sample of the fluid, it was full of bacteria that were subsequently identified as Pasteurella multocida. Unfortunately, he died shortly after admission.

Pasteurella multocida is a bacterium that can be found in many animal species but is classically associated with cats. It can be found in most (if not all) healthy cats, as well as in large percentages of other species such as dogs and rabbits. It’s an uncommon cause of infection in people, and is most often linked to cat bites or contact of cats with wounds or other breaks in body barriers. However, it can also be carried by people, and cats are certainly not the only source.

Here, the patient cared for several feral cats and they often slept in his bed (which to me, would make them more pets than feral cats, but that’s beside the point). The authors don’t specifically blame the cats, but it’s inferred. However, there was no investigation (for logical reasons, since it wouldn’t change anything).

Was the cat the source?

Probably, but not certainly.

Further, why the infection developed is a bigger, more interesting and more relevant question, since just being in the vicinity with a cat doesn’t mean you’re going to get an infection.

I often get asked about testing cats for Pasteurella multocida. My somewhat flippant (but still accurate) response is “Here’s the test: Does it look like a cat? If so, it’s carrying Pasteurella.” Cheap and highly accurate.

Seriously, though, it’s true. Most cats carry the bacterium so there’s no indication to test for it. If people are worried about Pasteurella infections (which is really uncalled for, since there are many greater risks in life), they should focus on good hygiene practices, bite avoidance and bite/scratch first aid, not determining whether their cat is carrying the bacterium.