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Can Flu And Allergy Shots Cause False Positive On A HIV Test?
Question: Hi,
I've been thinking of getting a standard STD testing but the thought of a false positive HIV test scares me. I've read that flu shots (which I get every year) and allergy shots (which I get every month) could cause a false positive. Are there any tests that this definitely could not possibly cause a false positive for? I once read that even with the PCR test you shouldn't get it near a flu shot (and by extension, I wonder about allergy shots), though I don't know if that's correct. I have very limited sexual history and limited risk. I'm doing this more so that a partner and I could show each other our results. I don't have any symptoms or think I'm actually positive. I've had unprotected sex only once in my life (about 15 years ago), protected sex only a handful of times (maybe 8 or 9), and given a few women oral sex a few times. My worst fear would be that all the tests will come back falsely positive for HIV and we'd never know it and think I was actually positive. (I'm a bit of a hypochondriac too.)
I meant to also ask, have you had patients on allergy shots who test negative for HIV? I don't know if they'd even share this information with you though. I've been getting the shots once a month for several decades.
I've been thinking of getting a standard STD testing but the thought of a false positive HIV test scares me. I've read that flu shots (which I get every year) and allergy shots (which I get every month) could cause a false positive. Are there any tests that this definitely could not possibly cause a false positive for? I once read that even with the PCR test you shouldn't get it near a flu shot (and by extension, I wonder about allergy shots), though I don't know if that's correct. I have very limited sexual history and limited risk. I'm doing this more so that a partner and I could show each other our results. I don't have any symptoms or think I'm actually positive. I've had unprotected sex only once in my life (about 15 years ago), protected sex only a handful of times (maybe 8 or 9), and given a few women oral sex a few times. My worst fear would be that all the tests will come back falsely positive for HIV and we'd never know it and think I was actually positive. (I'm a bit of a hypochondriac too.)
I meant to also ask, have you had patients on allergy shots who test negative for HIV? I don't know if they'd even share this information with you though. I've been getting the shots once a month for several decades.
Brief Answer:
Get done p24 antigen and Elisa test for antibodies.
Detailed Answer:
Thanks for your question on Health Care Magic.
I can understand your fear.
You are right about false positive results.
But with newer precise techniques, HIV testing in good laboratory is very accurate and chances of false positive results are very less.
So if you want to get it checked than get done
1. P24 assay
2. Antibody testing with Elisa.
If both are negative than no need to worry for HIV.
I have many patients with allergy shots and negative for HIV.
So no need to worry for this.
If you are negative than above mentioned tests will show negative results only.
Hope I have solved your query.
I will be happy to help you further.
Wish you good health. Thanks.
Get done p24 antigen and Elisa test for antibodies.
Detailed Answer:
Thanks for your question on Health Care Magic.
I can understand your fear.
You are right about false positive results.
But with newer precise techniques, HIV testing in good laboratory is very accurate and chances of false positive results are very less.
So if you want to get it checked than get done
1. P24 assay
2. Antibody testing with Elisa.
If both are negative than no need to worry for HIV.
I have many patients with allergy shots and negative for HIV.
So no need to worry for this.
If you are negative than above mentioned tests will show negative results only.
Hope I have solved your query.
I will be happy to help you further.
Wish you good health. Thanks.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Thanks for the quick reply. Is P24 the same thing as Western Blot? If Elisa is positive, does the same blood sample automatically get the Western Blot or P24 test? Or would I have to request it?
Brief Answer:
No both tests are different.
Detailed Answer:
Thanks for your follow up question on HCM.
I can understand your concern.
Both tests, p24 and western blot tests are different.
P 24 is antigen on HIV virus. It is detected by DNA PCR technique.
Western blot and Elisa tests detect antibodies.
Western blot is more specific than Elisa.
So first get done Elisa and if it is positive than you can go for Western blot (more confrimative) test from the same sample.
And if this comes positive than you ate confirmed HIV positive.
If your both are negative than you are confirmed negative.
Hope I have solved your query.
If you are not having further queries, then please close the conversation and rate my answer.
You can ask me directly on bit.ly/askdrkaushalbhavsar.
Wish you good health. Thanks.
No both tests are different.
Detailed Answer:
Thanks for your follow up question on HCM.
I can understand your concern.
Both tests, p24 and western blot tests are different.
P 24 is antigen on HIV virus. It is detected by DNA PCR technique.
Western blot and Elisa tests detect antibodies.
Western blot is more specific than Elisa.
So first get done Elisa and if it is positive than you can go for Western blot (more confrimative) test from the same sample.
And if this comes positive than you ate confirmed HIV positive.
If your both are negative than you are confirmed negative.
Hope I have solved your query.
If you are not having further queries, then please close the conversation and rate my answer.
You can ask me directly on bit.ly/askdrkaushalbhavsar.
Wish you good health. Thanks.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
OK - sorry to keep bothering you. Do you know if it's standard for a lab to do a Western blot on the same blood sample if Elisa is positive? Or do they first alarm the patient with the positive Elisa and then another blood sample is drawn?
Brief Answer:
No, you have to order western blot test separately.
Detailed Answer:
Thanks for your follow up question on HCM.
I can understand your concern.
No, laboratory will not do western blot test by its own.
You have to order western blot test separately.
Mostly laboratory tells patient about positive Elisa test.
Please let me know
1. Do you have fever or weight loss?
2". Do you have diarrhoea?
3. Do you have enlarged lymphnode in neck? "
Please reply me answers of above asked questions, so that I can guide you better.
I will be happy to help you further.
Wish you good health. Thanks.
No, you have to order western blot test separately.
Detailed Answer:
Thanks for your follow up question on HCM.
I can understand your concern.
No, laboratory will not do western blot test by its own.
You have to order western blot test separately.
Mostly laboratory tells patient about positive Elisa test.
Please let me know
1. Do you have fever or weight loss?
2". Do you have diarrhoea?
3. Do you have enlarged lymphnode in neck? "
Please reply me answers of above asked questions, so that I can guide you better.
I will be happy to help you further.
Wish you good health. Thanks.
Note: For further information on diet changes to reduce allergy symptoms or to boost your immunity, Ask here.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
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