Is HIV P24 Antigen Test Done 3-4 Weeks Post Exposure Conclusive?

Posted on Fri, 4 Aug 2017

Question: Hello sir;
I had a kidney stone pain around 5 weeks ago so i got a pain killer injection the concern i have is that i am confused whether the staff at clinic used a used a new syringe or not as the clinic was not a very big clinic and i went there in just a case of emergency as a result i had hiv1/2 p24 combo cmia test at dr lal path lab at 3 weeks,4 weeks and 5 weekswitth all coming back non reactive with a value of 0.08,0.07 and 0.06 respectively i want to ask whether the test i had is conclusive??whether i need any further test??

Answered by Dr. Sankaranantham Murugan (6 hours later)

Brief Answer:
You are free from HIV 1 infection beyond any doubt

Detailed Answer:
Hi,
Welcome to HCM.
Thanks for posting your query.
It is very much unlikely in any clinic to use an used syringe for some other person.
So, not have such odd suspicion.
Regarding the combo fourth generation tests reliability, there are two parts there in these tests.
P24 Antigen detecting part is conclusive by 3-4 weeks after the exposure. But it can rule out only HIV 1 infection which is the most common infection throughout the world except certain parts of XXXXXXX to the extent of 99% and above.
HIV 1 and 2 antibody detection part becomes conclusive by 12 weeks (window period) after the risk activity.
So you free from HIV 1 infection. If you want to be sure that you are free from HIV 2 also, then repeat the test once again by 12 weeks.
Dr S.Murugan

Above answer was peer-reviewed by : Dr. Prasad

Follow up: Dr. Sankaranantham Murugan (1 hour later)

Thanks alot sir for your encouraging reply,i know my worry is some what baseless but then too sir i am imaging the worst situation ,sir may i know in percentage how common is hiv 2 in XXXXXXX ,and one more thing i have little bit sore throat but only on one side i e left but bo problem in swollowing is that some thing related to my worry
Regards sir

Answered by Dr. Sankaranantham Murugan (3 hours later)

Brief Answer:
The chances of HIV 2 infection is a remote possibility.

Detailed Answer:
Hi,
Welcome back.

I can understand your concern.
If the used syringes are being used, then no one is safe. But it is not happening.

A sore throat (along with difficulty in swallowing) is a very common problem and can occur to any one at any point of time in a country like ours.

The incidence of HIV 2 infection is less than 0.5% in our country.

Not to worry. Transmission of HIV 2 is less common as it is less virulent. Transmission through used syringes is not common with HIV 2 infection.

Dr. S.Murugan.

Above answer was peer-reviewed by : Dr. Arnab Banerjee

Follow up: Dr. Sankaranantham Murugan (1 hour later)

Again thanks alot sir;
One last question from my side are intravenous or intramascular injectionmore dangerous in percentage when compared as the injection was injected through my hip and some people on internet say that the window period is six months is that true??and it is sure from ur side that i am free from hiv 1 infection??

Answered by Dr. Sankaranantham Murugan (6 hours later)

Brief Answer:
You are free from HIV 1 infection beyond any doubt

Detailed Answer:
Hi,
Welcome back.
Transmission through needles (intramuscular or intravenous) not makes much difference,
though intravenous has direct access for the entry of virus. Window period for HIV is within 12 weeks only for normal persons. People who are on immunosuppressive drugs like steroids will be likely to have delay in window period up to 6 months.
You are hundred percent free from HIV 1 infection.
Dr S Murugan

Above answer was peer-reviewed by : Dr. Kampana

Follow up: Dr. Sankaranantham Murugan (11 hours later)

Thanks alot sir ;
I have used some medicines for acne vulgaris i dont exactly remember the name but one was antibiotic and most of them were topically applying lotion about a year ago do you think that medicines may have steroids other than antibiotic i mean to say do dermatologist use steroids generally??
Regards and respect for your support

Answered by Dr. Sankaranantham Murugan (6 hours later)

Brief Answer:
You are free from HIV 1 infection beyond any doubt

Detailed Answer:
Hi,
Welcome back.

Basically I am a Dermato-venereologist and I knew well about the drugs used for Acne Vulgaris. Steroids are not indicated for Acne Vulgaris. Your drugs in no way influence the results of the outcome of HIV tests. So it is sure that you are free from HIV 1 infection.
Dr S.Murugan

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Sankaranantham Murugan (7 days later)

Hello dir once again,due to extreme anxiety i got tested again at 44 days through cmia duo test and by god's grace it again came back non reactive with index value 0.08 ,sir i want to ask you that what is the window period for hiv 2 and in one of your post i have heard that you saying that after four weeks cmia test is conclusive and you assuring that the person is hiv free ,one more thing due to my recent kidney stone operation i have devloped uti infection because of which i am feeling very weak and was having a mild fever of 99.4 -100 two days back ,can it be some thing related to ars symptom or its just because of uti infection???

Answered by Dr. Sankaranantham Murugan (4 hours later)

Brief Answer:
You are free from HIV 1 infection beyond any doubt.

Detailed Answer:
Hi,
Welcome back.

Your non-reactive HIV CMIA DUO test 44 days after exposure has not make much difference as the window period for HIV has not been completed.

Window period for HIV 2 infection also is same as that of HIV 1 infection.

You are free from HIV 1 infection.

Dr S Murugan

Above answer was peer-reviewed by : Dr. Arnab Banerjee

Follow up: Dr. Sankaranantham Murugan (17 hours later)

Thank you sir ;so sir as you said that i am free from hiv 1 beyond any doubt the weakness and other ill like feeling would be because of uti i am suffering from??and what is the chances in percentage of mine getting hiv 2 infection???

Answered by Dr. Sankaranantham Murugan (4 hours later)

Brief Answer:
You are free from HIV 1 infection. Chance of HIV 2 is remote.

Detailed Answer:
Hi,
Welcome back.
You are HIV 1 free and possibility of HIV 2 infection is almost 'nil ', in your case. Your symptoms are not related to HIV.
Dr S Murugan

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Sankaranantham Murugan (26 hours later)

Thanks alot sir!!!!,,ill get checked at 12 weeks mark just for peace of my mind and which test should i opt for cmia or simple antibody test at 3 months mark??thanks and regards!!

Answered by Dr. Sankaranantham Murugan (6 hours later)

Brief Answer:
All the HIV tests available in the market are highly reliable.

Detailed Answer:
Hi,
Welcome back.
Simple antibody detection tests (rapid) for HIV are reliable up to 97-98% whereas the CMIA duo 4th generation test is reliable up to 99% or more. Simple rapid test is most often enough to rule out both HIV 1 & 2.
I am sure that you will see the nonreactive test report in the 12 weeks mark test also.
Dr S.Murugan

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Sankaranantham Murugan (2 days later)

Thankyou so much sir for your reply,one more question how common is hiv 2 transmission with used syringe(if in worst situation he used ) i am from north india(uttarpradesh) how common is this disease in this region .and according to your experience of so many years have you ever seen any case turning positive after seven weeks negative cmia test??

Thanks and regards

Answered by Dr. Sankaranantham Murugan (3 hours later)

Brief Answer:
Transmission of HIV 2 infection through contaminated syringe is unlikely

Detailed Answer:
Hi,
Welcome back.
HIV 2 infection is less than 0.5 % prevalence in XXXXXXX I never came across a single case of HIV 2 infection transmitted through contaminated syringe.
98% of my cases are referred from other doctors with various manifestations (that is 7-10 years after exposure). I am yet to encounter a case HIV non-reactive by seven weeks after the risky contact became seropositive afterwards.
CMIA 4th generation HIV test is available only for the past two years in our country.
So our experience in this regards is not much.
Dr S Murugan

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Sankaranantham Murugan (4 minutes later)

Thanks alot again sir,so i could relax and strongly hope for non reactive result at 12 weeks mark??

Answered by Dr. Sankaranantham Murugan (16 minutes later)

Brief Answer:
You are almost free from HIV infection.

Detailed Answer:
Hi,
Welcome back.
You can relax even now. HIV 2 Transmission through contaminated syringe is quite unlikely.
Dr S Murugan

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Sankaranantham Murugan (8 hours later)

Thanks alot!! Sir with your blessings and confidence i am totally allaying fears of hiv
Thanks and regards

Answered by Dr. Sankaranantham Murugan (15 hours later)

Brief Answer:
You are most welcome.

Detailed Answer:
Hi,
You are welcome.
Relax.
Dr S.Murugan

Note: For further follow up on related General & Family Physician Click here.

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar