That might be your opinion and experience, JG, it's not mine.
>when they're treating animals who have contracted an avoidable zoonosis
You do realise that it is very difficult to diagnose lepto as opposed to many other diseases?
See:
https://vcahospitals.com/know-your-pet/leptospirosis-in-dogs-the-disease-and-how-to-test-for-it"Does the DNA-PCR test always work?
The DNA-PCR is an excellent test, but it has limitations. Most importantly, the DNA-PCR test must be done before the dog is given antibiotics. Leptospira are easily killed by antibiotics, and even small doses can make it difficult to detect infection using DNA-PCR. The test is most useful in the early stages of moderate to severe disease, when large numbers of bacteria are present. Dogs that have been sick for a long time or have only mild signs of illness may be difficult to diagnose by DNA-PCR due to the small numbers of bacteria present.
In some cases, dogs that are truly infected may give a negative result on the DNA-PCR test (false negative). This is especially common when antibiotics are given before the test is done. It is important to remember that a negative result does not rule out infection. If leptospirosis is suspected and the DNA-PCR test is negative, further testing must be done to confirm infection. This usually means doing the microscopic agglutination test (MAT).
In very rare cases, the DNA-PCR may be positive even when true infection is not present (false positive). It usually occurs in dogs that have been in contact with another type of Leptospira, one that does not cause disease. These dogs are not ill and usually have unremarkable routine test results. For this reason, routine testing should always be completed before testing for leptospirosis by DNA-PCR.
What is the MAT test for leptospirosis?
The MAT or microscopic agglutination test detects the presence of antibodies against Leptospira in a dog's blood. If the level of antibodies (called a titer) is high enough or can be shown to be rising over time, then infection is confirmed.
Does the MAT always work?
The MAT is an excellent test, but it also has limitations. It is a slower test than the DNA-PCR test and it may take several days to get results back from the laboratory. Sometimes a follow-up test (called a convalescent sample) is needed to confirm infection, which delays the diagnosis even further. Also, test results can be inconclusive if the patient has been previously vaccinated for leptospirosis, or if antibiotics were given early in the course of disease before the immune system had time to start producing antibodies."
Any vet who is finding a lot of DIAGNOSED lepto cases is a rare vet indeed. I even asked my own vet, who hadn't had a CONFIRMED case in 5 years. Lepto symptoms can present as a wide variety of different alternative diagnoses and the tests available are flawed and problematic. So it's simply a mistruth to state that vets can just look at their own practices and how many cases they get...
Of course,
vets who are already biassed in favour of giving lepto vaccinations can decide that things are lepto when they are probably not...