I've been looking on line for answers. So take these things with a grain of salt, esp. since I'm not a vet. But then I'm not sure most vets see enough FeLV to really be that knowledgeable about it.
What I've been able to understand from what I was able to find: ELISA tests for for FeLV free (unattached to other cells) in the bloodstream. This shows initial infection. The IFA tests for the virus attached to white blood cells (white cells are made in the bone marrow, which is where they pick up the virus) This shows secondary infection, & is when the cat starts sheddiing the virus & is contagious to other cats. I would treat ANY cat testing positive on Either test as contagious. The article below explains the life stages of the virus.According to this an IFA should ONLY be used after a positive Elisa. An IFA run without an Elisa may miss the initial stage of infection because it is only looking for FeLV in the white blood cells. http://www.lbah.com/feline/felv.html I really wish I was still in school & had the time to research & write about this subject! Beth Don't Litter, Fix Your Critter! www.Furkids.org ________________________________ From: Maureen Olvey <molvey...@hotmail.com> To: felvtalk@felineleukemia.org Sent: Wednesday, August 3, 2011 1:15 PM Subject: Re: [Felvtalk] Viral Shedding OMG - way to complicated for me!!! “I am not interested to know whether vivisection produces results that are profitable to the human race or doesn’t….the pain which it inflicts upon unconsenting animals is the basis of my enmity toward it, and it is to me sufficient justification of the enmity without looking further.” – Mark Twain > Date: Wed, 3 Aug 2011 10:09:17 -0700 > From: create_me_...@yahoo.com > To: felvtalk@felineleukemia.org > Subject: Re: [Felvtalk] Viral Shedding > > This link explains what "sheeding" a virus means. > > http://en.wikipedia.org/wiki/Viral_shedding > > Don't Litter, Fix Your Critter! www.Furkids.org > > > > ________________________________ > From: Natalie <at...@optonline.net> > To: felvtalk@felineleukemia.org > Sent: Wednesday, August 3, 2011 10:38 AM > Subject: Re: [Felvtalk] doubts on two FeLV positive kitties > > I think that their immune systems are getting rid of the virus by "eating it > up", "absorbing" it, NOT expelling it to infect others. I bet they don't > know....I will ask my vet next time I see him.... > > -----Original Message----- > From: felvtalk-boun...@felineleukemia.org > [mailto:felvtalk-boun...@felineleukemia.org] On Behalf Of Maureen Olvey > Sent: Wednesday, August 03, 2011 10:32 AM > To: felvtalk@felineleukemia.org > Subject: Re: [Felvtalk] doubts on two FeLV positive kitties > > > That's what we're wondering - whether the virus is shed into their saliva > while their immune system is still fighting the virus. If the ELISA is > positive but the IFA is still negative are the cats able to infect another > cat. My book said that when the IFA is positive the cats are able to infect > other cats. It didn't say that about when the ELISA is positive but the IFA > is negative. It didn't say anything at all about that situation so we're > wondering at what point in the progression of the disease is the cat able to > infect another cat. Since the ELISA test can use saliva or blood to detect > the virus then that means the virus is in the saliva at that point right, > and I would think it would be able to infect another cat. But that may not > be correct. Maybe the virus can't be spread until it's progressed all the > way through the body and has gone into the white blood cells. Maybe once > the virus goes into the bone marrow and white blood cells it changes or > mutates into a way that makes it contagious. I don't know, it's weird. I > guess if the experts don't know then I'll never figure it out either. > > > "I am not interested to know whether vivisection produces results that are > profitable to the human race or doesn't..the pain which it inflicts upon > unconsenting animals is the basis of my enmity toward it, and it is to me > sufficient justification of the enmity without looking further." - Mark > Twain > > > Date: Wed, 3 Aug 2011 10:10:37 -0400 > > From: at...@optonline.net > > To: felvtalk@felineleukemia.org > > Subject: Re: [Felvtalk] doubts on two FeLV positive kitties > > > > So, does that mean that as positive kittens'/cats' virus is being fought > by > > their immune systems, they are contagious? I have heard vets use the term > > "shedding" in this context since the 90s, NOT meaning that they are > > infectious during that time. > > What a little word can mean..... > > > > -----Original Message----- > > From: felvtalk-boun...@felineleukemia.org > > [mailto:felvtalk-boun...@felineleukemia.org] On Behalf Of Beth > > Sent: Wednesday, August 03, 2011 9:50 AM > > To: felvtalk@felineleukemia.org > > Subject: Re: [Felvtalk] doubts on two FeLV positive kitties > > > > Shedding a virus means they are contagious. > > > > Beth > > > > Don't Litter, Fix Your Critter! www.Furkids.org > > > > > > > > ________________________________ > > From: Natalie <at...@optonline.net> > > To: felvtalk@felineleukemia.org > > Sent: Wednesday, August 3, 2011 9:19 AM > > Subject: Re: [Felvtalk] doubts on two FeLV positive kitties > > > > Are we talking about two kinds of shedding of the virus? > > When I say shedding the virus, I mean that as the immune system develops, > > the body gets rid of the virus. > > Could it also mean that as the virus infects while shedding? > > > _______________________________________________ > Felvtalk mailing list > Felvtalk@felineleukemia.org > http://felineleukemia.org/mailman/listinfo/felvtalk_felineleukemia.org > > > > _______________________________________________ > Felvtalk mailing list > Felvtalk@felineleukemia.org > http://felineleukemia.org/mailman/listinfo/felvtalk_felineleukemia.org > _______________________________________________ > Felvtalk mailing list > Felvtalk@felineleukemia.org > http://felineleukemia.org/mailman/listinfo/felvtalk_felineleukemia.org _______________________________________________ Felvtalk mailing list Felvtalk@felineleukemia.org http://felineleukemia.org/mailman/listinfo/felvtalk_felineleukemia.org _______________________________________________ Felvtalk mailing list Felvtalk@felineleukemia.org http://felineleukemia.org/mailman/listinfo/felvtalk_felineleukemia.org
