Hypothesis for HSV Prophylaxis?

[wiltshire]

Dear all,

 

I have been doing a lot of reading around the subject of HSV treatment, pathology and search for vaccines or prophylaxis. I am not an immunologist by a long way, nor a microbiologist. I do work in the paramedical professions and have a better than average lay understanding of the subject.

 

I understand from another forum that manufacturers valacyclovir, famciclovir etc do not know the answer as nobody has researched it.

 

So the hypothesis is this (based on the papers I have read. I'm sure I could source them at request)....

 

"If 'ciclovir treatment is started as soon as possible after HSV exposure (up to 5 days after) it has been shown to greatly improve prognosis of the infection. It has also been shown that 'cyclovir suppressive treatment takes 5 days to take full effect, which also suppresses viral shedding. It is hypothesised that, prophylactic 'cyclovir treatment of an hsv-seronegative person will help protect against hsv infection from their seropositive partner, further improved if both partners take the medication".

 

Immunologically speaking, what would the immune response be to a virus (dead or alive) that has already been exposed to 'cyclovir during the initial "challenge" in a seronegative person. I'd like to think that (best scenario) it would prevent that infection and thence all future challenges having 'learned' the correct response to HSV....essentially, immunity.

 

Is there any logic here, or am I missing the boat completely. As I say, I am by no means an expert.

 

Many Thanks

[Psycho]

Normally due to HSV being a retrovirus the drugs target the RNA dependant DNA polymerase as this protein is used by the virus but isn't present naturally in the body so inhibiting it won't harm the body, but will stop the virus being able to replicate.

 

If taken constantly yes it would prevent infection by the virus, unless of course it mutated, but everyone would have to take it all the time or at least enough to create herd immunity, the problem isn't severe enough for that approach to become common practise.

[wiltshire]

That is a very encouraging answer. I have also found that there is such a protocol of 'cyclovir treatment for seronegative transplant patients in case they come into contact with HSV.

 

I know that manywith HSV wish to protect their partners from being infected. Yet this course of prophylactic treatment is never discussed or considered. Can it really be a blind spot? Cyclovirs are well tolerated by most, even for long term use, but are always looked at as treatment for the seropositive patient e.g. as a supressive therapy against shedding and or symptoms. It is never considered for a seronegative partner.

 

Are there others that concur with Psycho?

[Psycho]

Well the whole reason it isn't is because unlike a vaccine the drug would have to be re-administered regularly for example acyclovir is supposed to be administered 5 times a day, where as I am sure it could be increased too a week but maybe not so.

 

Not to mention it not being full effective so the drug would have to be throughout the body in quite high levels due to the virus being contracted via skin contact.

 

It could work but it would be a lot of hassle for not much gain,not too mention that I would doubt the long term, high concentration of the drug most likely hasn't been tested.

[wiltshire]

Thanks again psycho,

 

In this case what are considered high doses?

 

I also found this link here which suggests long term use is acceptable, if I read it correctly.

 

Valacyclovir and Famcyclovir are also alternatives derived from acyclovir with better, I think it's called "bioavailability" in that it gets into the system more easily and stays longer. Long-term suppressive HSV Valcyclovir therapy for seropositive patients is usualy 1x500mg tab/day (up to 1000mg/day for serious cases)

 

If this information is not readily available is a bit of an oversight as it represents at least an option for partners and couples to enjoy a full sex life without fear of infection, or at least a very seriously reduced risk. Agreed, it's not a vaccine, but it could potentially resolve many psychosocial issues amongst sufferers.