[Question #7592] HPV vaccine and transmission

3 months ago

My ex-girlfriend who I was with for a year and broke up with in July 2020 showed strains of HR HPV in her pap smear in august. I am sure I have it too. I was her last sexual partner until then. If I start a new relationship with someone who has only been in a monogamous relationship or even a virgin or let us assume with someone who does not have HPV or at least the same type as I probably do, how safe will she be after receiving the vaccine? Just to Err on the safe side that I might take a while or maybe even end up not clearing the virus despite being 25 y/o how likely is the vaccine to protect a new partner who does not already have any strains of HPV. Is it effective 100% of the time or how small is the chance of a new partner still getting infected despite receiving the vaccine? Since the vaccine’s effectiveness lasts somewhere around 10-14 years does that mean that if I marry that person, she will need to get it every ten years or so in case I were to reactivate? If I get the vaccine too, can it help preventing reactivation of the same strain if I end up deactivating it?

 are condoms not necessary after the new partner has been vaccinated, if they are recommended, for how long since there is not a way of testing men?

 if I were to go back with my ex-girlfriend who also shares the same strain what is the likelihood of passing the infection back and forth, or delaying clearance due to altering viral loads from the unprotected sex? According to this study reinfection within a couple is possible.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2600292/

This study demonstrates that HPV is efficiently transmitted between sexual partners and that multiple transmission events can occur within a couple. The rates of genital transmission from women to men were substantially higher than from men to women. Greater rates of female-to-male transmission should imply higher HPV prevalence in men. Studies in men to date, including our own cohort, have reported male genital HPV prevalences at least as high as in women, with most reporting prevalences of at least 20% and up to 73% (9,19). The penis shaft was the primary source of transmission to the cervix; the cervix and urine were the primary sources of infection to male genitals.

in a monogamous relationship where “the horse is long out the barn already” what precautions can be taken to prevent reinfection or delaying deactivation/clearance. I have read that using condoms can prevent increasing each other’s viral loads, if this is the case, would it be a good idea to use them until her pap smears comes back clear and she has been vaccinated to protect from being reinfected by the same strain in case I did not clear it and she did. I know I’ve already asked this but, how safe is it to have condom-less sex after receiving the vaccine to prevent transmission assuming one person has and active strain and the other one doesn’t due to clearance or never having been exposed? How soon after the second injection is it safe to start unprotected sex?  what are the odds of transmission to the uninfected partner after receiving the vaccine assuming they will be in a monogamous 10,20,30-year long relationship?

You can probably see that I’m the type to worry, but I really don’t want to put someone who does not have a positive pap smear at risk of being infected with HR HPV nor would I like to continue reinfecting a partner who already has it, as according to this study I shared, may happen. I know I’m giving you two different scenarios regarding relationships, but I see both as a possibility, especially the first scenario with a new partner who we are assuming is not infected, they’re either virgin or just haven’t been exposed. I know statistically speaking most people are likely to have been exposed but just for the sake of this scenario let us assume that this new potential partner has never been.

 

Thank you in advance. 

H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
3 months ago
Welcome to the forum. Thanks for your well thought out and sophisticated question. (If you're not a medical professional, I'd bet you could play one on TV!) I'm happy to help.

My first thought is that you seem to have misinterpreted the scientific paper you cite. It is a well done study by respected investigators. However, it does not address or draw conclusions about couples transmitting the same HPV strain back and forth. If that happens at all, it is rare. Rather, the study found that many sexually active couples are infected with more than one (sometimes several) HPV strains at any point in time. Ongoing sex in monogamous couples transmits some or all those strains, accounting for new infections in partners. But after a few months of infection, people are immune, or at least highly resistant, too new infections with the HPV type they already have, and therefore couples do not "ping pong" their mutual HPV infections back and forth. Further, I'm unaware of data that consistent condom use would reduce what already seems to be a small chance of transmission.

Second, I would encourage you not to worry about potentially having HPV or infecting partners. Most people in the dating scene are likely to have sex with a few partners before (until perhaps one day forging an ongoing mutually committed relationship), and you already understand (your comment about 20-73% prevalence of HPV), that it can be assumed that most potential partners already have had HPV, probably more than once, and many or most are currently infected. Having sex with one more infected partner (you) will not significantly increase the risk that they become infected or have a future health problem from HPV. And of course if they've been vaccinated, their risk of infection from you is zero or close to it.

I'm not aware of data that HPV vaccine efficacy wanes after 10-14 years. It is true that anti-HPV antibody levels decline with time, but that doesn't necessarily mean they are susceptible to new infection, and to my knowledge no public health agencies recommend HPV vaccine boostering. I'm not saying this isn't beneficial -- but it simply isn't known yet, at least not with sufficient consistency to have resulted in recommendations for re-vaccination. Any new partner you may have can be assumed to be fully protected if she has been vaccinated (for the 9 HPV types covered by the vaccine).

You can safely assume your own infection will not be continuously active -- although you are correct that delayed reactivation is fairly common. Part of your question includes "...can it [the vaccine] help in preventing reactivation...?" The answer is possibly yes, but this remains unclear. Initial research suggested no such benefit, but more recent studies suggest that there may be some benefit of vaccination against preexisting infection. However, if so, the effect probably is modest at best; and it is entirely unknown whether any such benefit is further enhanced by repeat (booster) vaccination.

Unfortunately, nothing is known that helps prevent HPV reinfection, speed clearance, or delay reactivation. It's logical to assume that major immunosuppression (advance HIV, chemotherapy, immune suppressing drugs) might do so, but there actually are little data on this. Progression of HPV to cervical or anal cancer is elevated in HIV infected persons, but most experts think this is more related to their overall higher risk of HPV in the first place than it is to immune deficiency. The one well established risk factor is tobacco smoking:  smokers clearly have higher rates of cervical cancer and apparently speed of progression of dysplasia to overt cancer. Of course the common sense stuff applies:  balanced diet, weight control, exercise, good sleep habits may have benefit in keeping immune systems healthy and strong, but no data have shown any obvious effect on HPV clearance, reactivation, or disease progression.

I think those comments cover most of the issues you raise, but let me know if I missed something or if any of this is unclear.

HHH, MD
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3 months ago

Dr. Handsfield. Thank you for the information you have provided. I understand you will need to close this thread soon; I tend to keep raising questions unendingly so I’ll just ask all I can while it’s allowed. Besides these are short consultations and not ongoing discussions so I understand. These are my current questions.

what is the likelihood of passing the infection back and forth, or delaying clearance due to altering viral loads from the unprotected sex? I read a comment somewhere that viral loads are increased when couples who share the same strain have unprotected sex which can end up delaying clearance, I assume the same would be true with protected(condom) sex since there’s still skin to skin contact. So if this is true ideally abstinence would prevent delayed clearance?

By the way I think you already addressed this in this comment

“Unfortunately, nothing is known that helps prevent HPV reinfection, speed clearance, or delay reactivation.

but I’m still curious about this idea of increasing each other’s viral load and delaying clearance, the person who mentioned it was told this by her Dr., reportedly, so she’s using condoms as prevention for increasing her and her partners viral loads so clearance is not delayed, what’s your knowledge or opinion on this subject of increasing viral loads through unprotected sex between couples with mutual strains? If this is true I’m assuming that it’s better to abstain all together to prevent increasing each other’s viral load since there’s still skin to skin contact even with condoms.

I found a study that, if I understood it right, seems to support this subject.

Of the HPV-positive couples, 57.8% of the men had the same HPV type as their partners; this rate was significantly higher than that expected by chance (P < .001). Moreover, these HPV-concordant men had higher penile scrape viral loads than did the non-HPV-concordant men. 

Conclusions: In sexually active couples, HPV type concordance was more prevalent than expected by chance and was associated with increased viral loads. These data provide biological support for HPV transmission between sex partners.

https://pubmed.ncbi.nlm.nih.gov/16080082/#:~:text=Conclusions%3A%20In%20sexually%20active%20couples,HPV%20transmission%20between%20sex%20partners.

 

 Ongoing sex in monogamous couples transmits some or all those strains, accounting for new infections in partners. But after a few months of infection, people are immune, or at least highly resistant, too new infections with the HPV type they already have, and therefore couples do not "ping pong" their mutual HPV infections back and forth. Further, I'm unaware of data that consistent condom use would reduce what already seems to be a small chance of transmission.

 

I’d like to share these findings and ask for your knowledge on this also..

 

·         If a person is infected with an HPV strain that clears, some but not all persons will have a lower chance of reinfection with the same strain. Data suggest that females are more likely than males to develop immunity after clearance of natural infection.”

https://www.immunize.org/askexperts/experts_hpv.asp#:~:text=are%20continuously%20infected.-,If%20a%20person%20is%20infected%20with%20an%20HPV%20strain%20that,after%20clearance%20of%20natural%20infection.

“In theory, if you and your partner have been infected with one type of HPV, you should now be immune to that type. This means you should not get it again. However, studies have shown that natural immunity to HPV is poor and you can be reinfected with the same HPV type.”

If my partner or I have HPV, will we keep passing it between each other?

“We are still learning about how HPV reinfection works between couples. Current evidence suggests that natural immunity to HPV , and going on to develop an immune response that would protect against reinfection, is poor, so there is a possibility that reinfection between couples could happen.”

https://www.jostrust.org.uk/information/hpv/faqs#:~:text=In%20theory%2C%20if%20you%20and,with%20the%20same%20HPV%20type.

Slyvia L. Ranjeva, a PhD student in the department of ecology and evolution at the University of Chicago and the Pritzker School of Medicine, and colleagues said the findings, published in the Proceedings of the National Academy of Science, suggest that infection with HPV16 does not induce protective immunity in men the way other viruses often do. The results also highlight the importance of vaccination before sexual contact to prevent initial infections.

“suggest that infection with HPV16 does not induce protective immunity in men the way other viruses often do”

My questions is, if this last quote is correct and the infection does not induce protective immunity in men as other virus do, it’s still possible to get re-infected with the same strain, so being in a monogamous relationship it may be that men can continue reacquiring the infection until his sexual partner clears it because reinfection is still possible, if it’s possible from reactivation of the virus, why wouldn’t it be possible to re-acquire the same active strain from a sexual partner, ?

https://www.healio.com/news/infectious-disease/20171215/men-with-hpv16-at-20fold-increased-risk-for-reinfection-after-1-year

The results also show that men who are infected once with HPV16, the type responsible for most HPV-related cancers, are at 20 times higher risk of reinfection after one year, and 14 times higher after two years. The researchers saw the same effect in both men who are sexually active and celibate, suggesting that they are not reacquiring the virus from another sexual partner.

 

 

The risk of HPV reinfection between a monogamic couple is still a

matter of debate [9-11]”

 

https://www.researchgate.net/publication/221743233_Incidence_of_human_papillomavirus_infection_in_male_sexual_partners_of_women_diagnosed_with_CIN_II-III

 

The risk of HPV reinfection between a monogamous couple is still a matter of debate.”

file:///C:/Users/User1/Downloads/S0213005X16000847.pdf

 

https://www.uchicagomedicine.org/forefront/biological-sciences-articles/men-with-hpv-are-20-times-more-likely-to-be-reinfected-after-one-year

it seems that women are more likely than men to develop immunity, to me it sounds like a man would have to wait for the women to be cleared first to then begin clearing it himself (in a sexually active monogamous relationship) since his chances of reinfection are higher but apparently, they decrease with time. What I am getting out of these articles (which I don’t know how valid they are) is that some people go on to develop natural immunity or at least be highly resistant and some don’t, it doesn’t say most however, but it looks like women are more likely to do so.  Is there any data on the likeliness of developing immunity or high resistance to the same strain you already have? And if there is, is there data on what the chances are based on gender (male or female)?

Some researchers state that the risk of reinfection between monogamous couples is “still a matter of debate”, this doesn’t sound like they’re convinced that most people are immune, or at least highly resistant, to new infections with the HPV type they already have.

I can’t help wondering these things. thank you for your answers.

H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
3 months ago
I'm sorry, but this is going way beyond the scope of this forum. Follow-up comments are allowed to permit clarifications of the initial question and responses to it. The moderators do not have an hour to devote to reading and replying to such extensive questions. My general response is that you are seriously over-interpreting theoretical or research information that doesn't necessarily have day to day application.---