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Dr Basu
Dr Basu, Experienced Specialist
Category: Medical
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Experience:  MD
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What are the chances of getting false negatives on both a pcr

Resolved Question:

What are the chances of getting false negatives on both a pcr rna test done at 18 days post possible exposure, (insertive partner vaginal for about 20 seconds after condom broke) and a rapid finger prick test at 7.5 weeks? Feeling unwell and sweating after minimal activity.......
Submitted: 3 years ago.
Category: Medical
Expert:  Dr Basu replied 3 years ago.
Dr Basu :

Hi there, This is Dr Basu, Experienced Specialist. I am here to address your concerns and provide great service.

Dr Basu :

Let's first start with the risk of HIV from 20 sec vaginal sex.

Dr Basu :

The risk is about one in 1000 cases or 0.01%

Dr Basu :

That is very low risk.

Dr Basu :

The accuracy of PCR RNA test at about 18 days is above 99%.

Dr Basu :

So, less than 1% chance the test will be falsely negative.

Dr Basu :

The finger prick test at 7.5 weeks is also very accurate again about 98%

Dr Basu :

So, both the negative tests coupled with such a low risk of infection to begin with, essentially rules out HIV infection.

Dr Basu :

The sweating and unwellness are likely from anxiety and may be a harmless virus ( cold or flu type) from the environment.

Dr Basu :

Best wishes,

Customer: Thank you dr
Dr Basu :

Very welcome

Dr Basu :

It was my pleasure to help you today.
I am Dr Basu experienced in Infectious Diseases.
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