Disease transmission from stray cat

We are currently attempting to catch a cat who showed up a few days ago.  We believe he is either a stray or feral cat or someone's neglected cat.  He appears to be intact and VERY hungry.  I have not been able to fully assess his condition but he appears healthy and I don't know how thin he is due to his thick, long hair(he's a seal point with deep blue eyes).  He's very shy but I've been able to get him to come within grabbing distance from me by leading him over with a trail of treats.  Tomorrow we're borrowing a live trap and hopefully it will work and this guy can be neutered, vaccinated, and adopted out.  Yesterday we managed to get him to come into our backyard(where we failed to catch him).  I'm concerned about our own cats coming in contact with anything he/other neighborhood cats have come into contact with.  How much of a concern is this?  Can FeLV really be spread so easily?  Some of our cats are allowed to have supervised backyard access while two walk on a harness.  I don't vaccinate anymore(they've all received vaccinations previously) due to some medical concerns.  Should we be more cautious?  It's clear that cats have entered our yard and urinated(also around our house) which is one reason we're eager to get this new guy neutered and re-homed.  

In my experience, FeLV is not that highly contagious as long as they are not fighting.  It is easily transmissible in a bite wound however.  The respiratory viruses are much more contagious so you might want to make sure your cats are immunized against those every three years or so if they are going outside at all.

I agree with Red Top.  Its wise to not  take foolish risks, but with normal caution, you shouldnt get any big extra risks on your residents.

Take a quarantine period & a vet check up with him, like with everybody else new rescued, but you dont need to get scared.

Of course, if this with medicals concerns [you mention] means a lower immunity in your residents, you must be extra careful with extra strict quarantine, but its not much of his doing.

Anyways, as they DO go out, they meet some extra bacterias and viruses anyway.   With a healthy cat, it reinforces his immune system.  With a cat with depressed immune system, it may be dangerous.   Distemper for example, gives very easily contagion, as this virus manages to be [and survive] outside body some time.

Tx for caring!

Good luck!

We just brought him to our local no-kill shelter; he's in excellent hands.