infection with resistant virus and treatment

[zeb]

Hi,

I was wondering this: I know people can get infected by resistant strains. My questions are these:

01. Can this be an infection which cannot be succesfully treated with meds?
02. If so, how big is the chance of getting infected with such a strain?

Zeb

[thunter34]

Wow, zeb....to get a strain that was resistant to any and all forms of treatment?  Thus far, I am unaware of such an infection.  Even the recent reports of "super-infection" that have been in the news in recent years have been found to respond to some treatments (even though they had resistance to some of the most commen "first line" treatments). 

Who knows what the chances are of coming into contact with such a strain?  I don't even know how one would go about accurately getting such a statistical number.  This has a very 'Am I Infected?' feel to it! 

Guess we'll have to wait for input from the mods or "the resident eggheads" (as Matty calls them).

[newt]

Hello

In reverse order:

2. Broadly speaking, in the US/UK, 10% of people will start off with a resistant strain of HIV, +/-5% or so depending on where exactly you are. 

About half of these individuals will have resistance to some the nuke class of drugs (AZT, 3TC, Viread etc). About one fifth will have resistance to NNRTIs (Sustiva, Viramune).  About one fifth will have resistance to one/some PIs (Kaletra etc).  About one tenth will have resistance to two or more kinds of drug.

1. Resistance tends to complicate treatment, but not always . Depends on the mutation in question.

 For example, having the mutation M184V which causes 3TC resistance doesn't mean you can't use that drug effectively because this mutation also makes HIV extra susceptible to treatment by other drugs.  Having resistance to NNRTIs usually wipes that class of drugs, but you can still use PIs.

The very rare event of resistance to all three current classes of drugs traditionally used for first-line therapy does make things considerably more complex.  But there are new (and about to be licensed) drugs which an individual is unlikely to have resistance to, and which do well against resistant HIV, like Prezista, and these can be used for first-line treatment if needed.

The goal when treating resistant HIV is now to score an undetectable viral load.  So the docs (at least) are optimistic this problem can for the most part be overcome.

So, short answer....

better not to have resistance - not always problematic, but can be - uncommon - multi-drug resistance very uncommon - resistant HIV can be treated in nearly all cases and the treatment target is optimistic (ie achieving an undetectable viral load) <<< this last point assumes access to the full range/newest set of anti-HIV drugs.

If you are on meds, not taking them on time contributes to resistance developing <<< this  is how most people get resistance.

- matt