[Question #6283] HIV Risk Dentist

15 months ago

Hello doctors,

I'm reaching out because I am having anxiety in whether or not I should retest after a possible exposure. I went to the dentist a while back and was met with a new dental assistant that didn't come off as a knowledgeable person. I was given lidocaine through injection and was worried that the dental assistant may have poked himself and gave the needle with the barrel to the dentist or may have picked up a reuse needle. After this event I tested 5 weeks and 2 days later. I was wondering what the probability that I would have gotten it from there and if I need to retest? The dentist office has amazing reviews but I guess I am rather afraid that he did something to the needle.

This morning my wife woke up and passed out immediately with a persistent stomach pain on the lower left area of her stomach and I am worried that it might be because of not testing at 6 weeks. I took her to the ER and they did blood tests CBC and also urine test but did not find anything as the cause of the pain.

Thanks in advance.

Edward W. Hook M.D.

15 months ago

Welcome to our Forum and thanks for your question. I'll do my best to help and to reassure you that your dental procedures did not put you at risk for HIV and is unrelated to your wife's fainting episode (I hope she is feeling better).

The activities which occur in dental offices are highly regulated and have multiple barriers to reduce the risk for transmission of infections, including HIV. Irrespective of what you thought of the dental assistant who helped the dentist, the chance that he/she had HIV OR stuck themselves with the needle used to draw your lidocaine into the syringe is close to zero. Further, your 5 day/2dy test results for HIV are highly reliable and virtually rule out any realistic possibility that you acquired HIV. I really see no reason whatsoever to worry about this event

I hope that this comment is helpful. Please don't worry. I hope that your wife is feeling better. EWH

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15 months ago

Hello Dr Hook,

Thank you for responding to my question. I wanted to get a somewhat accurate mathematical probability to help my mind at ease.

In my city of 1 million adults there are about 7000 that have HIV. The chance that the dental assistant had it or that any blood on an existing needle had HIV on it would be 7000/ 1 million. Assuming 10 percent chance of infection by needle injection and a 2 percent chance of the HIV duo test missing the infection I came up with around 99.99% chance I do not have it. Seems like great odds lol. But wanted to make sure I was doing the math right on it. Sorry for the over analyzing of the question, my job deals with analyzing problems. Haha

Edward W. Hook M.D.

15 months ago

I'm sorry you continue to worry. I think your numerical estimates are overly conservative. If you were stuck with a contaminated needle, the most widely accepted estimate is that the average risk for infection is about 1%, not 10%. Further, at five weeks the performance of a combination HIV antigen/antibody (duo) test is far better than the 2% error rate you suggest. Your risk for having become infected in the scenario you describes is a small fraction of 0.01%.

EWH

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14 months ago

One final question Doctor Hook, from all of your medical experience as well as Dr Handsfield, have either of you seen a result turn up positive after a 5 week negative duo test? If so what would you calculate as the percentage of it being a false negative? Thanks again and I hope you have a wonderful Thanksgiving.

Edward W. Hook M.D.

14 months ago

No, neither of us has ever seen or heard of persons with negative 4th generation tests at 4 weeks then go on to become positive, colleagues at the CDC say informally that they have seen this but again I am not aware of published reports. It must be extraordinarily rare- a very small fraction of 1%. I would not worry of I were you.

This ends this thread. As per Forum guidelines the thread will now be closed. EWH

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