Compared to husk in cattle it was just a few lines from my university notes....aelurostrongylus abstrusus...cat lungworm. "...but you won't see it very often, it's not very common and doesn't often cause clinical symptoms" or so I was told. Apparently though it's on the march. I was listening to Dr. Susan Little from the Bytown Cat Hospital in Ottawa, Canada at the London Vet Show talk about emerging infectious disease in cats. It's the most common feline pulmonary parasite and it's on the up, possibly due to changes in climate and the populations of the vectors it needs to spread from one host to another, or due to populations of their prey who may act as paratenic 'accidental' hosts. It's not just North America where it's been documented in many areas but closer to home....Italy, Portugal. In endemic areas apparently the prevalence of infection may be as high as 20-50% and it does cause symptoms, typically cough and anorexia due to bronchiolitis and interstitial pneumonia.

The thing about most emerging diseases is that they are not new; they've been around a long time, perhaps forever but for one reason or another they are on the up. Dr. Little talked about other emerging feline diseases, and you can find them in the London Vet Show proceedings, but mostly her talk was about aelurostrongylus, invasive aspergillus and streptococcus canis. Aspergillus of course causes disease across the species and I associate it in my head with guttural pouch mycosis in horses, but it doesn't transfer from animal to humans, animals are infected by spores from cat food, pet litter or the environment.

The bit of the talk that captured my attention most though was about streptococcus canis, the most commonly reported streptococcal pathogen in cats (beta-haemolytic, Lancefield Group G) for which she drew on her experience with large numbers of cats kept in shelters. For the most part Dr. Little said that we don't have to worry that much about streptococcus canis spreading to humans (unlike streptococcus equi subspecies zooepidemicus) although she did say that in cases of necrotizing fasciitis in cats due to S. canis it's as well to wear latex gloves/protective clothing to protect infection of skin breaks or cuts. What struck me though was when she talked about a case she had dealt with where as she described it in her talk "...I got this wrong". This was a case where initially she was unsure of what she was dealing with although it looked nasty, so she treated with quinolones, which are broad-spectrum. When the case didn't respond and the cultures came back she found that she was dealing with streptococcus canis - quinolones are not recommended for streptococcus canis infections because they are not particularly sensitive even if the in vitro results look good. For s. canis you need to be using good old fashioned beta lactam antibiotics.

Earlier this year I was watching a talk by a vet on the spread of antibacterial resistance in clinics in Southern Europe. This particular talk at BSAVA Congress showed that there is a bigger problem in Southern Europe than we have in the UK, but there was also a note of optimism in that there is evidence that changing prescribing habits does tend to reverse the trend and reduce the numbers of problem organisms resistant to antibiotics. Dr. Little clearly knows her stuff and stressed the importance of diagnosis to identify what you are dealing with which is basically the same message as that I heard at BSAVA.

Whenever I see a veterinary practitioner stand up in front of other vets and say, "...I got this wrong" I'm touched by it. I've seen it many times before from veterinary surgeons, particularly in the UK, often at clinical discussion groups over a beer. Most vets, even vets like Dr. Little who is clearly committed to what she is doing and keen to push standards, are very down-to-earth hands on people. Especially when I hear it from someone achieving something in their field I'm always moved by the humility of that "...I got this wrong." And whenever it happens I think that the profession of veterinary medicine takes one extra small step forward.