TRUVADA: Why are we ALL not taking this???!!!!

[trish]

THIS IS ABSOLUTE BULLSHIT!!!!!!!!!!!!!!

No, it’s mathematics using your numbers. Please see post and answer post 290 http://www.hungangels.com/vboard/sho...&postcount=290

Truvada is 1. More effective than condoms

This may be true. My argument grants that it is 99% effective (the number you posted).

2. Condoms are not needed in concurrence with Truvada in order to be effective.

If you’re happy with only a 74% chance of not getting infected within the next three decades, then yes...you won’t need to use condoms with truvada.


If for any extended period of time you expect to be engaging in behaviors where the effectiveness of truvada in preventing HIV infection is the advertised 99%/yr and you do not plan to supplement that protection then you will be putting your life and your health at serious risk: The probability that you won’t get infected by year N is (0.99) to the Nth power; i.e. (0.99)^N. The probability of getting infected with HIV by year N is (1-(0.99)^N).

On the other hand, assume the effectiveness of condoms is only 90%/yr. If you use condoms with truvada, then the probability getting infected the first year is the equal to the probability that both independent methods of prevention fail, namely (1-.99)(1-.9). So the effectiveness of the combo (condoms and truvada) is (1 - (1-.99)(1-.90)) 100% = 99.9%. The probability of getting infected by year N is therefore (1-(0.999)^N).

Using truvada alone, the probability that you will get infected sometime over the next 30 years is (1-(0.99)^30) = 0.2603.
Using truvada with condoms the probability that you will get infected sometime over the next 30 years is (1 - (0.999)^30) = 0.0296.

Below is a chart that compares the expected number of HIV infections between a group of 100 people who use truvada alone and a group of 100 who use condoms with truvada.

It may be the case that in the future truvada will be proven to be more than 99% effective over one year's use. In that case I'll revise the model. Perhaps I'm interpreting the reported effectiveness incorrectly (we already saw in this thread the difficulty in obtaining precise definitions of the published numbers). If nothing else, I think this comparison illustrates how well even a less effective supplementary preventative measure can amplify the effectiveness of your primary choice of prevention. WHATEVER ELSE YOU USE, USE A CONDOM, PLEASE.

[Westheangelino]

No, it’s mathematics using your numbers. Please see post and answer post 290 http://www.hungangels.com/vboard/sho...&postcount=290

This may be true. My argument grants that it is 99% effective (the number you posted).

If you’re happy with only a 74% chance of not getting infected within the next three decades, then yes...you won’t need to use condoms with truvada.


If for any extended period of time you expect to be engaging in behaviors where the effectiveness of truvada in preventing HIV infection is the advertised 99%/yr and you do not plan to supplement that protection then you will be putting your life and your health at serious risk: The probability that you won’t get infected by year N is (0.99) to the Nth power; i.e. (0.99)^N. The probability of getting infected with HIV by year N is (1-(0.99)^N).

On the other hand, assume the effectiveness of condoms is only 90%/yr. If you use condoms with truvada, then the probability getting infected the first year is the equal to the probability that both independent methods of prevention fail, namely (1-.99)(1-.9). So the effectiveness of the combo (condoms and truvada) is (1 - (1-.99)(1-.90)) 100% = 99.9%. The probability of getting infected by year N is therefore (1-(0.999)^N).

Using truvada alone, the probability that you will get infected sometime over the next 30 years is (1-(0.99)^30) = 0.2603.
Using truvada with condoms the probability that you will get infected sometime over the next 30 years is (1 - (0.999)^30) = 0.0296.

Below is a chart that compares the expected number of HIV infections between a group of 100 people who use truvada alone and a group of 100 who use condoms with truvada.

It may be the case that in the future truvada will be proven to be more than 99% effective over one year's use. In that case I'll revise the model. Perhaps I'm interpreting the reported effectiveness incorrectly (we already saw in this thread the difficulty in obtaining precise definitions of the published numbers). If nothing else, I think this comparison illustrates how well even a less effective supplementary preventative measure can amplify the effectiveness of your primary choice of prevention. WHATEVER ELSE YOU USE, USE A CONDOM, PLEASE.

While I appreciate the time you used to draw a graph, it is still doesn't change the fact that you don't understand how medications work or how their efficacy is gauged.

The initial study was over 18 months. When blood levels showed that Truvada was being taken at least five times a week NOT ONE PERSON BECAME POSITIVE. Guess who did? THE PEOPLE WHO DIDNT TAKE THE PILL!!!!

[Tapatio]

Wes, of all the people who regularly post here Trish is probably least likely to not understand something.

[trish]

...you don't understand how medications work or how their efficacy is gauged.

Perhaps I don't understand. Still I think the analysis I gave illustrates how well even a less effective supplementary preventative measure can amplify the effectiveness of your primary choice of prevention. Surely you don't believe that two people who expose themselves for different lengths of time take equal risks provided they're on truvada, do you? You're the one who said the effectiveness of truvada was 99%. Starting with your number and the assumption that you're only going to use travada with no other preventative measures, teach me how YOU calculate the probability of getting infected by year N.

[lifeisfiction]

Your body will build a resistance to any medication taken over a certain duration Furthermore the problem I find with Truvada is the initial statistical number of 99% effectives was a estimation of test participants taking the medication semi-properly over the designated period of time. Trish is right with the decrease of effectiveness. Comdons bare no substantial weakness over a period of time, because it is not a chemical agent, but a physical barrier.

Furthermore, the study was improperly concluded. The medication was not monitored under the ideal situation at should have been. The sample size of those who properly took the medication was almost non-existent. Instead they assume it would be more effective if a person had a large dose. The problem is the drug has traditional been given with other medication. It was never given solely as a treatment for HIV. So here you have a drug that researchers have not determine the effectiveness of the drug by itself. Simply put in a medical study you want to see the medication act under the ideal situation.

So you can believe its 99% effective, but in reality it will far less effective. It was poor study hence I would recommend proceeding with caution. For what I have glean from the many forums about people taking Truvada, they are treating it as an alternative for condoms. That in of itself maybe troublesome since the Truvada is not as effective. Truvada and condoms will provide excellent protection.

I am waiting to see those who are using Truvada exercise caution and care in choosing sexual situations that presents low risk. I think that in of itself will be a big determining factor for the perception and care of those who use Truvada. My fear is people really think this alone is all you need.

[Westheangelino]

^ And what of the studies with serodiscordant couples? Not one on Truvada came up positive.

Truvada IS a replacement for condoms and will stop the HIV epidemic IF ONLY MORE PEOPLE KNEW ABOUT IT.

Also, you say the sample size was nearly nonexistent? How many does it take to be existent?

[RobynBlakeTS]

Truvada IS a replacement for condoms and will stop the HIV epidemic IF ONLY MORE PEOPLE KNEW ABOUT IT.

No its not, with that thinking you'll replace an HIV epidemic with a herpes, warts, gonorrhoea, hepatitis epidemic.

Truvada does sound and could be a wonder drug but only in conjunction with condoms, not as a replacement to condoms.

[Westheangelino]

^ Condoms are not effective against herpes, warts, or hepatitis. Just so you know

[RobynBlakeTS]

^ Condoms are not effective against herpes, warts, or hepatitis. Just so you know

In your opinion they are not.

In mine they are, they wont 100% help but they do improve your odds so that is a good thing. Not using a condom only increases your odds of catching something so be sensible and use one in conjunction with truvada then your pretty much protected from HIV and from other STI's. Using truvada just on its own and wow you got a degree of protection from HIV but no assistance for protection from other STI's

[Westheangelino]

http://www.sfgate.com/health/article...es-3650285.php


It's not my opinion. None of these statements are opinions.