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Rapid HIV Testing in Udon Thani?


hkca

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Do yourself a favor and keep a supply of oralquick saliva hiv kits for self testing. Going to an hospital can get you out into a database. Hiv can lie dormant up to 10 years from your last encounter with the girl in question. Best to self test every 6 months. That way if you do develop hiv you'll catch it early and start treatment. Hiv is not a death penalty like in years passed. People, on medication, can live long lives.

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Do yourself a favor and keep a supply of oralquick saliva hiv kits for self testing. Going to an hospital can get you out into a database. Hiv can lie dormant up to 10 years from your last encounter with the girl in question. Best to self test every 6 months. That way if you do develop hiv you'll catch it early and start treatment. Hiv is not a death penalty like in years passed. People, on medication, can live long lives.

Per the OP the possible exposure is well in the past and not something he currently or habitually engages in so hardly need to test 6 monthly (and anyone who does, should seriously consider some lifestyle changes). A single test will do fine for the situation he describes.

Most importantly -- having an HIV test in Thailand does not put you into any special database and rumors like that, which could deter people from getting tested or treated, should not be spread.

Re the saliva based home test kits need to be aware that the rate of false negative results is almost 10 times greater than a lab blood test.

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An unhelpful post has been removed along with several spouting dangerously inaccurate information.

Posters are reminded of Health Forum rule #4:

2. Quackery and Misinformation: Posters should pay particular attention to forum rule # 1) "You will not use thaivisa.com to post any material which is knowingly or can be reasonably construed as false"....

This will be strictly applied with respect to presentation as fact any statements which are clearly contrary to medical science.

http://www.thaivisa.com/forum/topic/224498-health-forum-rules/

There is absolutely no doubt within the medical community that HIV causes AIDs (if untreated). Debates about this vanished decades ago in the face of overwhelming, rigorous scientific evidence, though some of these long out of date discussions still get dredged up on conspiracy theory websites. The science behind antiretroviral therapy for HIV is also rigorous and irrefutable. The drugs certainly have their side effects, but they have saved and are saving literally millions of lives.

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I have been told by several Doctors after having an HIV test that nothing can be confirmed 100% until a further test has been taken six months after the first. Not exactly sure what the first test results is really "saying" ?

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I have been told by several Doctors after having an HIV test that nothing can be confirmed 100% until a further test has been taken six months after the first. Not exactly sure what the first test results is really "saying" ?

This applies only if (1) the antibody test is what is referred to (there are other, more expensive tests that directly measure presence of even small amounts of the virus) and (2) the risk exposure was recent.

The reason is because it takes time for antibodies to be produced. 90-95% of people will have detectable antibodies one month after becoming infected. 98- 99% will after 3 months, and by 6 months essentially all (99.99...%) will.

So what an initial antibody test is 'saying" depends on when it was done in relation to the most recent date on which you could have become infected. If it is after one month, a negative result means it is 90-95% sure you are negative. If after 3 months, 99% sure and by 6 months you can be sure noninfected (assuming of course that you have not had any possible new exposures during this interval). Exact percentages vary with the brand of rapid blood test used but will all of them it is highly accurate but not 100% at 3 months and essentially 100% at 6 months. Saliva-based home tests are less accurate.

It is not that one has to be tested twice, it is rather a matter of time after exposure. Typically people get a test shortly after risky behavior so they will be advised if negative to repeat the test in another 3-6 months.

In the case of the OP, whose possible exposure was years ago, no need for more than a single test. If he was infected years back he will have ample antibodies by now.

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Maybe he is not only 5 years older but also 5 years wiser now. Perhaps he's done some reading up on it, enough to realize that relying on a test the girl had (or said she had) may not have been sufficient.

Not the first person to think back on prior exploits and realize they were a bit foolhardy. So let's cut him some slack.

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The above is completely incorrect. You confuse application for mass screening with individual testing and even there, your math is completely off. (Screening 1,000 people among whom 1% are HIV positive will yield on average 11 positive results, 9 of them genuinely with HIV and 2 false positives. So hardly "75% wrong". And the 2 false positives will of course be identified through routine confirmatory testing.) (The HIV prevalence among people who come in for testing is, of course, higher than that of the general population, since people come in to be tested for a reason.

A 99.6% sensitivity means that if an individual tested is HIV positive (and has formed antibodies, i.e. not in early stages of infection), there is only a 0.4% chance of a false negative result.

Sensitivity tells you nothing about false positives. That comes from the specificity rate. Varies according to the test kit in use, but usually between 99.1 - 99.9%, meaning that among people who test positive, it will be a false positive in under 1 percent of cases.

Even those small error margins do not apply to the final individual result though because there are fails safes. Blood samples testing positive on the rapid test are always then re-tested using Elisa/Western Blot. Whatever it may show in dogs, the Western Blot is >98% specific for HIV in humans, The chance of a false positive on both the rapid test and the Elisa or Western Blot is infintesimal....something like 1 in 10,000. This is BTW the reason results are given hours later or the next day - to allow time for confirmation testing first if the rapid test is positive. The rapid test itself gives results in just minutes.

Some clinics, especially those run by the Thai Red Cross, also do batch NAT testing in all blood samples used for rapid testing. This tests for the actual virus (as opposed to antibodies) and is extremely effective in picking up false negatives. For anyone concerned about a possible recent infection it pays to have the rapid test done in a facility which does this.

Thank you for pointing out that I should have used 'Specificity' not 'Sensitivity' .

However, you completely misunderstand the interpretation of a screening test as do most health professionals

https://www.stat.berkeley.edu/~aldous/157/Papers/health_stats.pdf

What if you were found to have a positive HIV antibody test? What is your chance of being truly HIV infected ?

If the Specificity of the test is 99.6%

Firstly you cannot begin to answer this question without knowing the prevalency of the disease or condition

HIV prevalency is determined is by the tests kits themselves. A completely circular methodology.

With a prevalency of 1% and a Specificity of 99.6% the test would be wrong 23 % of the time

However with a prevalency of (0.1%) 1/1000 persons are HIV infected.and specificity of 99.6% the test will be wrong 75% of the time

Moreover if you are arguably somewhat removed from the risk groups that dominate the statistics to say 1/2000 then the test would be wrong 89% of the time,in other words, almost all of the time.

99.6% is the probability that if you have the disease then you test positive, not the probability that if you test positive then you have the disease.

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I got my own tests from a friend that sells test kits for all manner of things (mostly illegal drug test kits). I freaked out when someone told me "remember that girl who..." and then "she died a couple of months ago from liver failure" (liver problem stories are often the front here for any manner of other things that might otherwise embarrass the family). I did my first test immediately, which is only a finger prick much like a diabetic test, on a test strip, and takes less than a minute. 3 months later I did it again to check it was the same negative result, as I was told that it can take time for symptoms to be measurable. I still keep some tests in the refrigerator, although they may be past their sell by date by now.

Anyhow, with all the googling I did, it seems if you're black and female, you can get HIV just by looking at it from a nearby street, and Caucasians, especially male in straight sex with no skin lesions are in the least likely category, with Asians being somewhere in between. It is a real threat, but an unlikely one.

Liver failure is not listed by the CDC as an AIDS defining disease. However, it is a growing cause of death by persons taking the combination of highly toxic drugs for the "suppression" of HIV .

And if HIV "prefers' to infect Homosexuals Males , African Americans Hemophiliacs and a large proportion of Sub Saharan Africa it is the first infectious disease that

" thinks" and chooses whom to infect

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The above is completely incorrect. You confuse application for mass screening with individual testing and even there, your math is completely off. (Screening 1,000 people among whom 1% are HIV positive will yield on average 11 positive results, 9 of them genuinely with HIV and 2 false positives. So hardly "75% wrong". And the 2 false positives will of course be identified through routine confirmatory testing.) (The HIV prevalence among people who come in for testing is, of course, higher than that of the general population, since people come in to be tested for a reason.

A 99.6% sensitivity means that if an individual tested is HIV positive (and has formed antibodies, i.e. not in early stages of infection), there is only a 0.4% chance of a false negative result.

Sensitivity tells you nothing about false positives. That comes from the specificity rate. Varies according to the test kit in use, but usually between 99.1 - 99.9%, meaning that among people who test positive, it will be a false positive in under 1 percent of cases.

Even those small error margins do not apply to the final individual result though because there are fails safes. Blood samples testing positive on the rapid test are always then re-tested using Elisa/Western Blot. Whatever it may show in dogs, the Western Blot is >98% specific for HIV in humans, The chance of a false positive on both the rapid test and the Elisa or Western Blot is infintesimal....something like 1 in 10,000. This is BTW the reason results are given hours later or the next day - to allow time for confirmation testing first if the rapid test is positive. The rapid test itself gives results in just minutes.

Some clinics, especially those run by the Thai Red Cross, also do batch NAT testing in all blood samples used for rapid testing. This tests for the actual virus (as opposed to antibodies) and is extremely effective in picking up false negatives. For anyone concerned about a possible recent infection it pays to have the rapid test done in a facility which does this.

Thank you for pointing out that I should have used 'Specificity' not 'Sensitivity' .

However, you completely misunderstand the interpretation of a screening test as do most health professionals

https://www.stat.berkeley.edu/~aldous/157/Papers/health_stats.pdf

What if you were found to have a positive HIV antibody test? What is your chance of being truly HIV infected ?

If the Specificity of the test is 99.6%

Firstly you cannot begin to answer this question without knowing the “prevalency” of the disease or condition

HIV “prevalency” is determined is by the tests kits themselves. A completely circular methodology.

With a prevalency of 1% and a Specificity of 99.6% the test would be wrong 23 % of the time

However with a prevalency of (0.1%) 1/1000 persons are HIV infected.and specificity of 99.6% the test will be wrong 75% of the time

Moreover if you are arguably somewhat removed from the risk groups that dominate the statistics to say 1/2000 then the test would be wrong 89% of the time,in other words, almost all of the time.

99.6% is the probability that if you have the disease then you test positive, not the probability that if you test positive then you have the disease.

again you are confusing issues around mass screening with the accuracy of the test for an individual patient.

Specificity and sensitivity rates are applicable to each individual tested independeng of what the prevalence of the disease is in the population.

Where prevalence comes into the equation is in deciding the cost-benefit of mass screening. And indeed mass screening is not recommended for general populations with low prevalence. Not because it will lead to prople receoving wrong results, since the false positivrs will be eliminated on confirmatory testing but because the final yield of true cases detected will be so low relative to the cost.

This has nothing to do with how to interpret an individual result.

BTW you'd be hard pressed to find a place with 0.1 prevalence. Modt low prevslence countries at least 3 times that. Still would not undertake mass testing of the general population in them though.

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As this thread has been hijacked by conspiracy theorist AIDS deniers determined to dpread the sory of misingormstion that led to some 300,000 ' 400,000 unnecessary deaths in Africa, and the information sought by the OP has been fully provided, the thread is now closed.

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