Several comments from forum users preceded my reply. I don't vouch for them, but in general it seems they are more or less on track. Please see many other threads on this forum for questions like yours for more detail, since your questions have been addressed many times. You can search for "Time to postive HIV test" and "HIV symptoms".
1) Antibodies appear and can be detected in most cases within 4-6 weeks of infection; it is rare for it to take longer, even though CDC and other authorities continue to stick to the historic advice to wait 3 months to be absolutely sure.
2) Serocconversion occurs within 4-6 weeks and ARS typically has onset a 7-14 days after exposure. In other words, most people seroconvert with a time course similar to that of ARS. Therefore, the answer is yes: 2 weeks after onset of ARS, almost everybody will have a positive antibody test--that is, they will have seroconverted.
Good luck-- HHH, MD
From what I have heard from an MD friend of mine, most if not all people will seroconvert and will have detectible antibodies by 25-27 days. That is why tests at 6 weeks are around 99% conclusive. Tests at 4-5 weeks are also pretty conclusive as well, but most reccomend 6 weeks. Now I got that bit of info from an MD friend of mine. The doc in here knows better so he will be able to clarify your question a little better than i can.
I'm curious, what's the exception or that remaining 1 percent? And why do some experts still insist on 3 months as conclusive and not before then?
I'll wait for the Doctor (or others more knowledgeable than I) to give you a more definitive answer, but I believe the remaining 1% or so are those with suppressed immune systems, such as individuals on chemotherapy. In addition, there are always exceptions to the rule, which is why the recommendation is to wait for 3 months to make sure that you are not the outlier. I had a very low risk exposure event 4 months ago, tested negative at 8 and 1/2 weeks, and my doctor wants to retest at 6 months to make sure that I'm definitely outside the window period. But that is due to the very unlikely possibility that I was infected in the first place. If I had a high risk exposure event, he would have likely recommended more frequent testing. Every case is unique, which is why you need to get tested as recommended by your doctor.
Joeworried pretty much summed it up. To add, nothing in science is 100%. Probabilities get as high as 99.999999999999+ or as low as .000000000000000000001- you get the point.
Joe, from what i have read and from what HHH has stated time and time again, 6 months is the old guideline for testing. 6 months is usually what GP's tell patients, but those guidelines are behind the times as HHH has stated before. 3 months is still the guidline for most states, 6 weeks for some.
At any rate, you can trust the words of Dr. Handsfield over most MDs if not all regarding STDs.
Please don't take this the wrong way as I believe your expertise is unparralled. But I have been reading the threads of "time to positive HIV test" and notice that sometimes you say that an ELISA/Oraquick test at 4 weeks will detect 80% of people yet in some other threads you mention at 4 weeks it is 90% or even 95% at 4 weeks. I guess the message you are trying to send is that 4 weeks it is very accurate but for some of the worried well the difference bteween 80% and 95% at 4 weeks can make a little difference in anxiety level.
So would you agreed that the time to positive is more like this
4 weeks - 80%
5 weeks - 90%
6 weeks - 99%
3 months - 100%
People need to stop beating themselves over the probability and odds issue with testing reliability. The doctor states 6 weeks is ~99% reliable. He never stated "definitive" odds for 2,3,4, week probabilities; I believe those probabilities are more or less estimated than anything. You cant beat HHH over these odds either. 6 weeks is the guidline that HHH and most others go by, or 3 months. Rely on the 6 week or 3 month test, but 3,4,5 week tests can offer reassurance to help ease anxiety levels.
A good illustration of the buildup of hiv antibodies with time (which indicates the effectivenss of the hiv antibody test) is given in an article by the state of New Jersey mentioned by JohnnyV last weekend. This article can be found at:
The graph on page 2 of this article illustrates the rapid buildup of hiv antibodies after 30 days.
So, you'd think they'd say 6 weeks is conclusive, with the caveat that if you're undergoing chemo or have had an organ transplant, or anything else that would categorize you as immunosuppressed, you should test out to 3 months.
From the New York State Health website
"With the HIV antibody tests used in New York State, virtually all people who are infected will test positive within one month of being infected. Most people will test positive even sooner.
The period between the time of infection and the time that a HIV antibody test can detect the infection is called the window period. During the window period, an infected person does have HIV and can pass HIV to other people, even if his or her HIV antibody test is negative.
So, if you HIV antibody test is negative, you can be sure that you do not have HIV only if you have not engaged in any HIV risk behaviors (such as having unprotected sex or sharing needles) during the past three months.
A PCR (Polymerase Chain Reaction) test looks for HIV directly instead of detecting antibodies. This test can find HIV infection as soon as the person is infected. It is usually used to find HIV infection in newborns. A different type of PCR test, called a viral load test, is used to measure the amount of HIV in the blood of someone who is already known to be infected. Doctors may suggest and HIV PCR test if they think a person has been infected with HIV in the past few days or weeks."
The State of Massacusetts uses the 6 week testing window. You can confirm this if you like by doing some google searches.
It is very difficult for individual states and organizations to contradict "official" CDC policy. Until the CDC changes its stance (which is not likely to occur in the near future), other organizations will simply defer to that policy. You also need to remember that doctors and health care agencies operate on a CYA approach. It is much better for them to remain conservative to ensure that everyone that is hiv positive is caught. New York State policy (which is mentioned above) calls for a test at 4 weeks and a follow-on test at 3 months. The intent is to catch (essentially) all hiv positive individuals quickly (at 4 weeks), while making sure than none have been missed (at 3 months).
How often and when you test is an individual decision. From what I have read on this forum and elsewhere, any negative hiv test after 6 weeks is definitive if you did not engage in a high risk activity. But that is simply my opinion.
I should have added that I had a low risk exposure event, and tested negative at 8 and 1/2 weeks. I'm comfortable with this result, and may or may not have another test depending on my future anxiety levels.
Good for you!! I wish you the best!!
BTW, my Google searches have been futile. I'm really curious to read what the State of Mass. has to say. Can you direct me to a specific site?
Try the following website.
If you read down the left column on the second page, where it says:
"It can take up to 6 weeks for your body to produce enough antibodies to be detected by the test. So a test today will tell you what your HIV status was 6 weeks ago."
The site is from the Massachusetts Department of Public Health, HIV/AIDS Bureau and is date June 2003.
This whole thread is so helpful - it makes me look at facts.
My facts: low risk exposure - symptoms at 9 weeks - test negative for everything at 11 weeks = negative. Thanks guys.
Now I just need to make sure that I don't put myself through this again.
Thanx again, Joe! That was very helpful!