The biggest problem that communities face with community cat programs is that no one takes responsibly for the medical needs of the cats. It is one thing to feed a neighborhood cat, but quite another to take on the responsibility to sterilize and vaccinate those cats. Many cat owners don’t do that for their own cats, let alone cats running loose in the neighborhood.
Although feeding these neighborhood cats is a humane act; that food creates at artificially high carry capacity for the neighborhood and triggers breeding. Within a few years the neighborhood population of cats explode, resulting in complaints to animal control. Generally, animal control doesn’t care about cat problems until complaints arise and then they set about to reduce the population to zero: resetting the population for the cycle to begin again.
A few communities have active Trap, Neuter and Release (TNR) programs to attempt to bring about community wide population stability. Those programs are only as successful as the staff and funding to constantly trap fertile cats. Feral cat colonies exist within communities to attempt to maintain a population stability in small pockets; however, cat owners see those colonies as a dumping ground for their own pets when they decide to abandon them.
You might imagine that finding homes for these “wild cats” might be the biggest issue for animals shelters; but, the disease that they bring into the shelters is the biggest problem. These unvaccinated cats become stressed by trapping and relocation to the shelter that trigger the expression of disease.
It is not uncommon to read about disease outbreaks of Feline Panleukopenia in local animal shelters. These outbreaks are usually the result of animal control personnel loading the shelter with feral cats. The disease is quite contagious and will spread quickly, when people come into the shelter wanting to touch every animal. In 2016/17, my shelter would get one outbreak under control, only to have animal control bring in more infected cats; we lived from one outbreak to another. Having animal control and the animal shelter under one department helps the two organization into moving in the right direction.
Most people, including TNR folks, are only worried about rabies, so the other contagious diseases are not addressed in the community. People who allow their cats to go outside should vaccinate their cats as directed by their veterinarian.
Many animal shelters vaccinate animals on intake, but the onset of protection is too slow to prevent an outbreak within the shelter. Control of shelter disease must start in the community. A good strategy for people wanting to surrender their pets is to request that the animal is fully vaccinated 30 days prior to surrender.