Hiya Max
Sorry to hear your news but all is not lost as cherry says. I am still negative but even if it does change I would choose to continue with tysabri. Having lost folk close to me I say chuck the best drugs u can at ms! We are all guinea pigs of some sort aren’t we and all the research/evidence may help someone else if not ourselves.
Ellie
Truesay Ellie.
Sorry to hear of your losses - were these fellow MSers?
Still wrestling between Ty and Tec - Just don’t know… 
Hi Max, can’t answer the question about tec and how they monitor you, sorry. I’m hoping by the time I have to come off ty that they have found a solution to the JC Virus problem. Good luck. Cherry
Hi Cherry - No probs.
So is Ty not considered to be a “lifetime” treatment?
I suppose obviously new drugs come on the market etc…
All the best 
Max
hiya max
yes they were friends of mine who had ms-i never use the term fellows msers
one took her own life leaving hubby and 2 kids behind, other who had a really painful life ms wise.
i have met many folk with ms and am so glad they have shared their stories with me. i feel in a better position to make my own decisions because of their honesty. i aint going to tell u my story-u have enough going on in yer heid for now!
ellie
I think at the first sign of PML they get you off Tysabri (natalizumab) so generally I guess there is the expectation to discontinue Tysabri at some time. I’m not on Tysabri but am on Tecfidera. With Tecfidera they monitor white blood cell count not JCV antibodies. (Very low white blood cell count causes weakness to infections other than by JCV.)
I’ve read on the Barts research blog that Fingolimod was the preferred drug to switch to from Tysabri so I thought it would be the option in your case too. I know that the general rule is that one has to have failed on interferon beta (now Copaxone too?) before Fingolimod is offered but since you are being offerred Tysabri? But I’m not a neuro or health professional of any sort.
The Barts blog also has a lot of information on Tysabri (natalizumab) and PML/JCV.
E.g.
http://multiple-sclerosis-research.blogspot.com/2015/01/clinicspeak-natalizumab-pml-update-q4.html
http://multiple-sclerosis-research.blogspot.com/2015/07/clinicspeak-derisking-natalizumab.html
If you go to their website you can search it.
Their is also a related site http://www.clinicspeak.com/
in particular: - Understand your risk of PML with Tysabri
Best wishes.
Jonathan