Okay, I'm by no means an expert but we have four cats.
Two have Feline Herpes and two do not.
From what I understand from the things my Vet had told me, Feline Herpes is contagious, but he said that most cats are exposed to the virus at some point in their lives probably as kittens and they develop an imminity to it....he feels that's the case with Annabelle and Elliott ( those are the two that don't have it ) since even though they've both been exposed to an outbreak neither has ever gotten sick.
Apparently one of the shots they get as kittens is for herpes, but if they already have the virus it won't get rid of it.
Once they have the virus they have it for life, although they may never have an outbreak they are carries of the virus.
As for lifespan, my Vet said they can live just as long as a cat without the virus as long as you stay on top of things...in other words IF they have an outbreak as long as you treat it...their lifespan will not be shorten by the virus.
We got Gracie and Lizzie when they were 6 weeks old and they had all of their shots.
I had no clue that they carried the virus until they were 4 years old.
Lizzie started to cough like she was trying to get up a hairball, frankly I thought she did have a hairball, but two days later she started to sneeze, her nose and eyes were running and her left eye was red...just like pink eye in a Human.
So off to the Vet and that's when I found out she had the virus.
The Vet told me at that time Gracie might have the virus also, but there was an equal chance that she didn't..he said she might have developed an immunity.
Gracie was fine until Christmas Eve of 2005, she was fine when we went to bed and when we woke up she had all the symptoms that Lizzie had had two years earlier.
So she also has the virus.
Gracie has never had another outbreak.
Lizzie was also fine until this November.
We brought Elliott into our home and two weeks later Lizzie had an outbreak.
The virus can lay dorment for long periods of time, but an outbreak can occur during times of stress, like moving, death of another animal in the family, or in Lizzie's case bringing another animal into the house.
The funny thing is, when we brought Annabelle in there was no outbreak.
It would seem the Elliott stressed her out more than Annabelle did.
I know I probably didn't really offer much help, just wanted to give you my first hand experiance with the virus and let you know that yes it is contagious, that some cats develop an immunity to the virus but that some don't and apparently there is no way to know if they are immune or not.