[Question #6448] Hpv

13 months ago
Got some hpv questions 
1 how effective is a condom against hpv for a one night stand

2 how long does it take for a infection to take hold. If I acquired it during one night stand and had sex 5 days later , can I infect partner 

3 what is the rate of  hpv infection per unprotected  episode , ex  50%

4 do you know why hpv 68 in not covered in vaccine 

Thanks 
Edward W. Hook M.D.
Edward W. Hook M.D.
13 months ago

Welcome to the Forum.  I happened to be on the Forum soon after your questions arrived so you are getting replies a bit more quickly than is typical.  Follow-up replies may take longer.   I'll be glad to address your questions.  In addition, I will encourage you to look at some of the numerous other posts on the Forum which address HPV - it is a frequent topic and looking at them will add to the information I provide. 

HPV is without a doubt, the most common STI. Over 80% of sexually active persons have HIV, no matter how few sex partners they have, Thus while most single exposures do not result in infection, most people already have it.  Further, the infection is innocuous for most persons, resolving on its own over time and resulting  no adverse outcomes.  For those who are at risk for adverse outcomes, following routine sexual health recommendations almost always allows early, precancerous lesions to be detected and easily treated.  The current HPV vaccine protects against 9 different HPV types, 2 (types 6 and 11) cause typical genital warts and 7 of which are called "pre-cancerous", a misleading term since only a small proportion of these infectious will progress to cancer if undetected and untreated.  With this as background, I'll try to address your questions;

1 how effective is a condom against hpv for a one night stand
Condoms remain among the most effective, non-vaccine ways of preventing STIs including HPV.  As I mentioned above, most single exposure do not lead to infection.  When used correctly and consistently condoms further reduce the risk for HPV about 60%. 

2 how long does it take for a infection to take hold. If I acquired it during one night stand and had sex 5 days later , can I infect partner 
There are no data to inform my response to this question.  Typically it takes 2-4 months for HPV infection to become detectable after acquisition.  I would guess that the risk for transmission, in the unlikely event that a partner does not already have HPV, is low

3 what is the rate of  hpv infection per unprotected  episode , ex  50%
As mentioned above, there are no data to answer this question.

4 do you know why hpv 68 in not covered in vaccine 
The types of HPV chosen for the vaccine were based on how common they are.  The 7 most common HPV types associated with pre-cancerous lesions are included in the vaccine.  HPV 68 is less common than the types included in the vaccine.

I hope that this information is helpful.  EWH
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13 months ago
I guess I’m just trying to do the math , if say most exposures dont lead to infection say 40 percent and a condom reduces it by 60 percent then there is a 16 percent chance ?
  
Can you be also that HPV 68 doesn’t show up in a lot of cervical cancer

Also I have read that overtime they reduce it by 60% but a one time deal could be up to 90 is that true

Edward W. Hook M.D.
Edward W. Hook M.D.
13 months ago

I wish I could be more precise with numbers but there just aren't studies to give you good numerical answer.  If anything, your estimate of a 60% chance is on the high side.

HPV 68 appears to be more weakly associated with genital tract cancer than other, more common types such as HPV 16 and 18.  there are not a lot of data on HPV 68

I am not sure what you mean by "Also I have read that overtime they reduce it by 60% but a one time deal could be up to 90 is that true".  Far less than 10% of HPV infections progress to precancerous lesions and well over 90% of such infections resolve without therapy on their own. EWH


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13 months ago
I meant to say a one time episode a condom is hpv  90 % effective but over time it’s reduced to 60 percent 

In your opinion what’s my odds of catching hpv from this condom protected sex 

 
Edward W. Hook M.D.
Edward W. Hook M.D.
13 months ago

This will be the final response to your questions.  As per Forum guidelines, following this response the thread will be closed without further responses.

You are correct that the 60% figure represents the reduction of risk related to multiple exposures.  There are no data to inform how much protection might be provided on a single occasion.  Sorry.

Although you have provided no specifics on your exposure, in closing I would like to remind you that your concerns are speculative and when you consider: 1. That if your partner had HPV 68 you do not know you acquired the  infection and 2.  And even if you did acquire HPV, there is a more than 95% chance that the infection will resolve over time.  Thus from our perspective, this is just not something to spend a lot of time worrying about. 

Take care. EWH

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