Unable to find genital herpes2 statistictic

[atlfriend]

I have been having a problem finding any research that gives the statistic that would indicate what the chance is of somebody contracting genital herpes2 FROM THE GENERAL POPULATION WITHOUT USING ANY PROTECTION. I am looking for the number out of 100 that would catch it in a year.
(I know the numbers of how many have it, how many don't know, and I have read a report on the research of what the chances are if you are using condoms with a infected person, the chances with an infected person using Valtrex and a condom and the chances using no protection with a infected person-these last 3 are assuming no sex during an outbreak.)

If you can help me with where to find it or what research has been done, I would really appreciate it.

Thanks

[atlfriend]

Thank you Dr. HHH and bad_choices.  The way it looks, numerically, the chances of infection with a unknown, untested partner, MIGHT be greater than a positive H2 person with regular Valtrex and condom use and no activity during outbreaks.

[H. Hunter Handsfield, M.D.]

There are no data available to answer your question, other than the sort of common sense calculation provided by bad_choices.  His estimate probably is on the high side.  For someone with a partner known to have genital herpes due to HSV-2; with that partner having had his/her herpes for more than a year; and avoiding sex during symptomatic outbreaks; and sex 3 times per week:  annual transmission rate is around 5%.  Add consistent use of condoms, which are at least 80% effective; plus Valtrex, which reduces transmission risk at least 50% (probably more):  then the calculation of transmission risk per year is 0.05 x 0.2 x 0.5 = 0.005, i.e. 0.5% (one chance in 200) per year.

But as bad_choices says, these are very rough calculations, and the risk undoubteldy is highly variable.  For example, there is no way to know whether the infected person is someone with a higher than average or lower than average rate of asymptomatic viral shedding; or how good s/he is in recognizing symptoms; or in how reliably s/he takes Valtrex.  And so on.

Best wishes--  HHH, MD

[bad_choices]

Around 25% of the population has HSV2.

For serodiscordant couples (one HSV2 positive and the other negative) who only abstain from sex during outbreaks but otherwise have sex regularly (say 2 times per week) the transmission rate is something like 7% per year (and I believe its a different rate for men and women -- higher for women than for men).

So if you use condoms and have regular sex with someone whose HSV status you don't know (and abstain from sex if your partner has an outbreak), you could estimate your chance in one year as roughly 25% of 7%, or just under 2%.

Of course this is very rough math.  Different demographics of people have very different rates of seroprevalence (for instance I believe the rate among african americans is 40-50%; and the rate for MSM is even higher), but this provides a start.