[Question #7138] HPV detection - older women

9 months ago
Hi,

Do HPV research DNA tests (HC2, PCR, etc) have the potential of detecting "dormant" HPV? In this case, my definition of dormant assumes non transmissible. I'm asking because I used to have HR- HPV that cleared and have noticed NIH redetection/reactivation articles out there, specifically for older women.  Is it possible that these HC2 and/or DNA PCR detection are picking up on DNA that is inactive? Again, I'm specifically asking about DNA tests (ignoring RNA PCRs for now). I'm just hoping this is a possibility in an effort to make myself feel better. Perhaps not all of these (if not most) redetections are not actually non transmissible dna material

I'm not a pro and this isn't my area so wanted to ask you all. Thank you.
9 months ago
In other words,
is it possible that when studies note "hpv detection" in older women that perhaps some of this is due to latent/dormant HPV that does not necessarily mean transmissible. Would the cutoff value for these tests make it to where this is not the case and all positives would imply active infection?
9 months ago
I'm asking this question in cases of normal cytology hpv positive in research studies of older women
Edward W. Hook M.D.
Edward W. Hook M.D.
9 months ago

Welcome to the Forum, thanks for your question(s).  I'll try to help.  Your question is a tough one as it deals with a topic of ongoing research.  The short answer is that following clearance of HPV DNA tests from a person who had infection previously detected, as is typically the case, the risk for subsequent forward transmission if very low.  Typically when commercially available DNA detection tests show that HPV has cleared, careful study over time, sometimes using ultrasensitive tests for HPV DNA show periodic, intermittent "shedding" of viral DNA. The significance of this low-level, intermittent shedding is the topic of ongoing research.   Most experts counsel women that clearing of detectable HPV means that those persons are unlikely to transmit their infections to others and they are at very low risk for progression to pre-malignant cytological changes.  This I suppose there is some slight risk for transmission to sexual partners and little or no risk for progression to cancer, particularly if the person continues to get periodic sexual health check ups including HPV testing. and I would not worry about transmission to new, uninfected partners. 

I should add that I note that in your first question you mention hybrid capture tests.  these tests are clearly less sensitive for detecting evidence of current or past infection when compared to other amplified DNA or RNA detection tests. 

The best prevention of transmission to uninfected partners remains vaccination.

I hope this information is helpful.  EWH

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9 months ago
Thank you for the response. I'm familiar with HPV "shedding".  I have a bit of a background in virology, and I personally think it's odd for HPV to "shed" decades after clearance. I can see this being a potential for the first 3-5 years or so after clearance, possibly even within 10 years post clearance, but not longer.  After all, this virus is very different from HSV where the shedding is conceivable and makes sense given the mechanics of that virus.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2698799/
In this article HC2 was used to assess HPV prevalence in women age 57-85 years old. Here are my questions:

1 - Is it fair to assume all of these positive results in women with normal cytology in this study are then transmissible and active? Alternatively, is it possible that some are due to dormant infections that are bringing up a positive result due to inactive DNA detection? Is HC2 sensitive enough to allow for that? A lot of these women with positive results had no new sexual  partners for over a decade plus.

2. Not to get too into the weeds here, but there is also the matter of integrated HPV (not capable of viral progeny or transmission) that can have active protein transcription - can this result in a positive HC2 test as it pertains to this study? (a simple answer for this would be best, I don't want to get too deep into this topic as it gets very complex and I am not qualified to speak to it much)

3. What does a positive test even mean (again, as it pertains to this study). Is it possible that some of these "detections" via HC2 are dormant detection due to genetic material being detected via the test.

Reminder - - - According to the manufacturer, HC2 can detect as little as 5,000 copies per ml ---
I also think the above article uses a  Digene Microplate Luminometer 2000 (for specimens with Relative Light Unit/Cutoff Values ≥ 1.0 - positive). Not sure if that is any more or less sensitive than HC2

Sorry - I know this is a lot. But this topic is very personal to me and I only know so much about the HC2 test. To keep things simple, all I am truly trying to ask is, is it possible that some of these positive results are indeed not transmissible and could be a result of dormant HPV.

Thank you very much for helping me.
Edward W. Hook M.D.
Edward W. Hook M.D.
9 months ago
The data on capital HPV shedding overtime are still emerging. On the other hand, we absolutely know that for other chronic viral infections such as herpes, shedding can occur decades after the initial infection although the frequency of that process the clients overtime.  Studies of HPV are ongoing.

In response to your follow-up questions:
1.  Unfortunately at the moment my access is limited and I am not able to reach the article you have cite at the moment.  Your question however implies that it is possible that DNA detected in shedding studies is not infectious. Infectivity increases as the amount of virus present increases for sure. You are also correct that, on occasion , most often following therapy, fragments of viral DNA may be detected by PCR type tests.  It seems unlikely however that nucleic acids detected years after clearance of infection do not represent replicative virus.  The sensitivity of the hybrid capture essay is well known to be lower than other nucleic acid amplification tests.

2.  Sorry, I cannot comment on that.  

3.  Unlikely.

I’m sorry I have not been able to provide more detailed answers. I will try to access the paper and you have mentioned at a later date. That said, You seem quite focused on the HC assay, a test which is not as sensitive as newer, more sensitive nucleic acid amplification tests.  I also am also not sure why you are so concerned about transmissibility when the consequences of transmission are so minimal.  More later.  EWH
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9 months ago
I appreciate your answers. Seems like what I'm asking is unknown. I do feel, however, that if it was indeed a high possibility, then the data would be there simply because if something (post clearance transmission) occurs in large noticeable numbers, we would be prompted to investigate. Regardless, I will take your advice for now, hoping new research doesn't hit us like a brick later down the line.

You ask why I was so focused on the HC assay? Because that is what my linked article used to detect hpv in older women. Thus, it seems that, based on your answers, these does indeed represent viral replication - noted.

Here is the original article I linked to you :
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2698799/  uses HC2 and Digene Microplate Luminometer 2000 (DML 2000) to detect HPV

It might be interesting to contrast the above article  to this one
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4753489/

"The persistence of virus in these samples cannot be attributed to a latent infection as usually defined6. Implicit in the definition of viral latency is the capacity to synthesise new viral progeny. HPV genome integration marks the end of the virus life cycle and the loss of this capacity, consistent with the absence of HPV16 E4 expression, a viral biomarker of productive infection, in these samples... we believe we have provided the first robust estimate of the prevalence of silent HPV16 DNA in morphologically normal cervices of older women...Our findings help illuminate a number of previously puzzling aspects of the exposure-disease relationship in older women24,25,26. The observation that HPV positive older women are less likely to have a contemporaneous abnormal smear than HPV positive younger women could reflect the emergence in later life of integrated but transcriptionally silent high-risk HPV types."
This article uses Luminex PCR

I am trying to see if it is possible virus detected via HC2 nd DML in article 1 could indeed be integrated (transcriptionally silent HPV) as found in article 2, or if the fact that detection was obtained via HC2 instead of something more sensitive (PCR) rules this out entirely. - assume this to be the question of the reply, please.

Again, this is a lot. I will more than happily purchase a second question for this. I think it would be good to quickly glance at both documents. Given my brief stint with virology as well as personal experience with HPV, this is interesting for me and I need help interpreting the above.

Thank you again.
9 months ago
"It seems unlikely however that nucleic acids detected years after clearance of infection do not represent replicative virus" - why not? If HPV can be latent (as a virus) then why cant Nucleic acids  be detected years later? These could be latent episomal or integrated virus nucleic acids ... why does DNA detection immediately imply replication or active virus?

If one is simply amplifying DNA, how could the assay distinguish between active or inactive infection? If HPV can lay latent, then the same can be said for detecting the virus years and years later? Now, if this was Reverse Transcription PCR (RT PCR) we would be detecting mRNA (actively transcribed genes), which could point to an active infection... even then, it could be integrated HPV virus which is not transmissible.

I think, perhaps, these later detections in older women could simply be inactive (non-transmissible) virus? Is HCII capable of this? Am I incorrect in my above logic ^ (again, this is no longer my field and some of what I'm saying could be misunderstood on my part)
Edward W. Hook M.D.
Edward W. Hook M.D.
9 months ago

I have reviewed the second article you provided a link to but am unable to successfully open the link to the first reference you provided.  The second article uses research techniques which are not commerically available to explore the issue of HPV latency but acknowledges that interpretation of the results are challenging and that HPV nucleic acids found in cervial tissue in their study may or may not be replicable.  All nucleic acid detection tests detct only a small fragment of the targeted DNA (or RNA) and thus may detect replicable (viable) organisms of non-viable nucleic acid fragments.  When nucleic acid fragments are present the body typically processes and elimantes them over time.  Thus for virus that has cleared, the closer to the time of clearance (or treatment in other cases), the more likely it is that the nucleic acids represent non-viable, residual nucleic acid fragments that have not yet been eliminated.  It would seem that the more distant in time that nucleic acid fragments are detected, irrespective of which detection test is used, the more likely it is that the presence represents replicable virus.  As I said in my original response however, "The significance of this low-level, intermittent shedding is the topic of ongoing research.   Most experts counsel women that clearing of detectable HPV means that those persons are unlikely to transmit their infections to others and they are at very low risk for progression to pre-malignant cytological changes."  This remains the case.

In the interval since m ylast reply I have also discussed your questions with other experts.  They agree that your questions touch on a subject on ongoing research, and debate.  I am not a HPV molecular biologist and your questions go in that direction.  My sense is that while you raise academically interesting and as yet unressolved questions, the answers you seek are beyond the mission of this Forum which is to provide clinical information to our clients as well as questions beyond my level of expertise.  I have little more to offer to you. 

As you know, we provide up to three responses to each client.  This is my 3rd response.  Thus this thread will be closed shortly without further replies.  I will add in closing that I worry that, as at least implied above, you are overly concerned over the possiblity of recurrence of your previously cleared HPV infection.  I suspect that if this the case, these concerns are misdirected and a distraction and would urge you to instead follow guidelines for regular follow-up, a practice which would serve you well and is ov proven benefit to women with past HPV infections.  Take care.  EWH

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9 months ago
Understood. Thank you. I may purchase a second question for a quick clarification on that last point. I am good for now. Thanks!