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What Is The Correct Window Period For HIV Antibody Test?

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Posted on Tue, 23 Aug 2016
Question: What causes some people antibody to not show up after 3 months of a hiv antibody test? And how rare is it that a test will be false neg after 3 months?
doctor
Answered by Dr. Bruno Mascarenhas (44 minutes later)
If there is no antibody after 3 months, It means that the individual is not affected

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar
doctor
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Follow up: Dr. Bruno Mascarenhas (1 hour later)
Ive heard cases online where ppl show up false negative after 3 months and id like to know what causes that and why doctors want to test another 3 months later?
doctor
Answered by Dr. Bruno Mascarenhas (2 hours later)
Brief Answer:
If the Immune System is Very Poor, there will be Viremia and not Antibodies

Detailed Answer:
Hi,

Welcome to HealthCareMagic.com I am Dr.J XXXXXXX Anto Bruno Mascarenhas. I have gone through your query with diligence and would like you to know that I am here to help you.

You can test for presence of HIV Infection by two ways
1. Measuring the Virus
2. Measuring the Antibodies
If both are negative at 3 months, then the patient is not infected

-oOo-

Let me explain this a bit more

TESTS FOR VIRUS

RNA tests — show a positive result based on the presence of the virus. These tests are more expensive than anitbody tests, so are not offered in as many places. 9-14 days after infection, there will be enough viral material for a positive result.

PCR tests (Polymerase chain reaction tests) — also test for the actual virus. This type of test is often used for testing the viral load of HIV-positive people, as well as testing babies born to HIV-positive mothers. 2-3 weeks after infection, there will be enough viral material for a positive result

-oOo-

TESTS FOR ANTIBODIES

Antibody tests ("Rapid" tests) — give a positive result based on antibodies to HIV, not the virus itself. It takes your body up to 3 months to produce these antibodies at levels that can be detected by this test.

12 weeks (3 months) after infection, most of people will have enough antibodies to test positive.

-oOo-
As per Spivak, XXXXXXX M; Sydnor, XXXXXXX RM; Blankson, XXXXXXX N; Gallant, XXXXXXX E (AIDS. 2010;24(10):1407-1414) Over one million people are estimated to be living with HIV-1 in the United States, and more than 16 million people are tested for HIV-1 annually. According to United Nations Programme on HIV/AIDS epidemiologic data, in 2008, there were 33.4 million people living with HIV/AIDS worldwide and 2.7 million incident infections. Since HIV-1 was first recognized, however, there have been only 25 published case reports of patients with confirmed HIV-1 infection who do not have detectable HIV-1 antibodies.

This means
There is less than a million chance of the person being infected with HIV Virus and yet not developing Antibodies

-oOo-

Even the very negligible group of people who do not have antibodies will have virus present at 3 months.

So
At the end of three months, if both Tests for Virus as well as Tests for Antibodies are negative, we can be sure that the person is not infected.

-oOo-

So
If you want to be sure

Please do both Tests after three months
1. Tests for Virus
2. Tests for Antibiodies

If both are negative, you can be sure that the person has not been infected

Hope you found the answer helpful.

If you need any clarification / have doubts / have additional questions / have follow up questions, then please do not hesitate in asking again. I will be happy to answer your questions.

Best Wishes for Speedy Recovery
Let me know if I can assist you further.
Take care.

-oOo-

PS 1 : After all your doubts have been cleared, kindly (a) Close this Question (b) Rate my Replies and (c) Give your Feedback.

PS 2 : In the future, for continuity of care, I encourage you to contact me directly in HealthCareMagic at http://bit.ly/askdrbruno
Above answer was peer-reviewed by : Dr. Nagamani Ng
doctor
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Follow up: Dr. Bruno Mascarenhas (40 hours later)
How accurate are test after 6 months? Can there still be false negative and if so what are the causes? Would it be health realated issues?
doctor
Answered by Dr. Bruno Mascarenhas (9 minutes later)
Brief Answer:
If Both Tests are negative after 6 months of expos, patient is not infected

Detailed Answer:
Dear Sir

If BOTH
(1) Test for Virus
and
(2) Test for Antibodies
are negative after 6 months of exposure
Then the person is not affected

Even in those who are infected and in whom Antibody tests are negative, the Virus will still be found

So
If you want to be sure

Please do both Tests after three months and also at six months
1. Tests for Virus
2. Tests for Antibiodies

If both are negative, you can be sure that the person has not been infected

Hope you found the answer helpful.

If you need any clarification / have doubts / have additional questions / have follow up questions, then please do not hesitate in asking again. I will be happy to answer your questions.

Best Wishes for Speedy Recovery
Let me know if I can assist you further.
Take care.

-oOo-

PS 1 : After all your doubts have been cleared, kindly (a) Close this Question (b) Rate my Replies and (c) Give your Feedback.

PS 2 : In the future, for continuity of care, I encourage you to contact me directly in HealthCareMagic at http://bit.ly/askdrbruno
Above answer was peer-reviewed by : Dr. Arnab Banerjee
doctor
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Follow up: Dr. Bruno Mascarenhas (4 minutes later)
So there is no way at 6 months both test will come out false negative?
doctor
Answered by Dr. Bruno Mascarenhas (9 minutes later)
Brief Answer:
Clarified !

Detailed Answer:
//So there is no way at 6 months both test will come out false negative?//

If a patient had been infected, One of the tests will be positive 6 months after exposure

If both tests (Test for Virus and Test for Antibodies) are negative 6 months after exposure, then the person is not infected

Best Wishes for Speedy Recovery
Let me know if I can assist you further.
Take care.

-oOo-

PS 1 : After all your doubts have been cleared, kindly (a) Close this Question (b) Rate my Replies and (c) Give your Feedback.

PS 2 : In the future, for continuity of care, I encourage you to contact me directly in HealthCareMagic at http://bit.ly/askdrbruno
Above answer was peer-reviewed by : Dr. Arnab Banerjee
doctor
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Follow up: Dr. Bruno Mascarenhas (12 minutes later)
So you are saying at 6 months there should be a undoubtly high enough viral load to show up on the test?
doctor
Answered by Dr. Bruno Mascarenhas (10 minutes later)
Brief Answer:
One of the two will be there

Detailed Answer:
//So you are saying at 6 months there should be a undoubtly high enough viral load to show up on the test?//

At the end of 6 months after exposure,
There will be either Viral Load
or
Antibodies

One of the two will be present

If both are absent, then patient was not infected 6 months ago

Let me know if I can assist you further.
Take care.

-oOo-

PS 1 : After all your doubts have been cleared, kindly (a) Close this Question (b) Rate my Replies and (c) Give your Feedback.

PS 2 : In the future, for continuity of care, I encourage you to contact me directly in HealthCareMagic at http://bit.ly/askdrbruno
Above answer was peer-reviewed by : Dr. Arnab Banerjee
doctor
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Follow up: Dr. Bruno Mascarenhas (16 minutes later)
So you are positive that either one of the test will show up at 6 months if i am hiv positive?
doctor
Answered by Dr. Bruno Mascarenhas (19 minutes later)
Brief Answer:
Had you been infected 6 months ago, One of the two would be positive

Detailed Answer:
//So you are positive that either one of the test will show up at 6 months if i am hiv positive?//

YES
Had you been infected 6 months ago, One of the two would be positive

If both tests (Test for Virus and Test for Antibodies) are negative 6 months after exposure, then the person is not infected

Let me know if I can assist you further.
Take care.

-oOo-

PS 1 : After all your doubts have been cleared, kindly (a) Close this Question (b) Rate my Replies and (c) Give your Feedback.

PS 2 : In the future, for continuity of care, I encourage you to contact me directly in HealthCareMagic at http://bit.ly/askdrbruno
Above answer was peer-reviewed by : Dr. Arnab Banerjee
doctor
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Follow up: Dr. Bruno Mascarenhas (10 minutes later)
So there has never been any case in medical history that both test would come out false negative at the 6 month mark?
doctor
Answered by Dr. Bruno Mascarenhas (7 minutes later)
Brief Answer:
Both will not be false negative 6 months after exposure

Detailed Answer:
//
So there has never been any case in medical history that both test would come out false negative at the 6 month mark?
//

Both tests (Test for Virus and Test for Antibodies) will not be false negative 6 months after exposure

Let me know if I can assist you further.
Take care.

-oOo-

PS 1 : After all your doubts have been cleared, kindly (a) Close this Question (b) Rate my Replies and (c) Give your Feedback.

PS 2 : In the future, for continuity of care, I encourage you to contact me directly in HealthCareMagic at http://bit.ly/askdrbruno
Above answer was peer-reviewed by : Dr. Arnab Banerjee
doctor
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Follow up: Dr. Bruno Mascarenhas (8 minutes later)
So taking both at 6 months would be 100% accurate results?
doctor
Answered by Dr. Bruno Mascarenhas (4 minutes later)
Brief Answer:
Taking both tests six months after last exposure

Detailed Answer:
//So taking both at 6 months would be 100% accurate results?//

Taking both tests (Test for Virus and Test for Antibodies) six months after last exposure would give 100 percent accurate results

Let me know if I can assist you further.
Take care.

-oOo-

PS 1 : After all your doubts have been cleared, kindly (a) Close this Question (b) Rate my Replies and (c) Give your Feedback.

PS 2 : In the future, for continuity of care, I encourage you to contact me directly in HealthCareMagic at http://bit.ly/askdrbruno
Above answer was peer-reviewed by : Dr. Arnab Banerjee
doctor
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Follow up: Dr. Bruno Mascarenhas (4 minutes later)
One more question... Why would one test come out negative if another comes out positive. Im just curious and like to know the most i can. By the wayYou been awesome so far.
doctor
Answered by Dr. Bruno Mascarenhas (15 minutes later)
Brief Answer:
If the B Cells are defective, then antibodies will not be manufactured

Detailed Answer:
//One more question... Why would one test come out negative if another comes out positive. Im just curious and like to know the most i can. By the wayYou been awesome so far. //

Antibodies are manufactured by the bodies immune system (B Cells) against the Virus

If the B Cells are defective, then antibodies will not be manufactured
So
The tests which are used to detect antibodies will give false negative

But
In that case, there will be large amounts of viruses in Blood
So
Tests which will detect Viruses will be positive

Let me know if I can assist you further.
Take care.

-oOo-

PS 1 : After all your doubts have been cleared, kindly (a) Close this Question (b) Rate my Replies and (c) Give your Feedback.

PS 2 : In the future, for continuity of care, I encourage you to contact me directly in HealthCareMagic at http://bit.ly/askdrbruno
Note: For further follow up on related General & Family Physician Click here.

Above answer was peer-reviewed by : Dr. Raju A.T
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Answered by
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Dr. Bruno Mascarenhas

Neurologist, Surgical

Practicing since :2000

Answered : 813 Questions

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What Is The Correct Window Period For HIV Antibody Test?

If there is no antibody after 3 months, It means that the individual is not affected