Welcome to the forum. I'll try to help. Questions about HPV and oral sex are quite common these days, due to a number of media stories about it, and about throat cancer related to HPV. I'm taking the opportunity to write a blog-like response that will help in responding to other questions in the future.
The bottom line is that the risks are low. This is an area of active research, and new data will emerge as the years pass. But the best information now is that the genital HPV strains don't take very well in the oral cavity; infection can occur, but is a lot less common than genital infection, even in persons who have performed oral sex on infected partners. When oral HPV occurs, it almost always remains asymptomatic (e.g., oral warts are very, very rare) and clears up on its own. Although throat cancer due to one genital HPV strain (HPV-16) is rising in frequency, it remains a very rare disease, with probably around 10,000 cases per year in the United States -- compared with millions and millions of oral exposures to the virus.
Every sexually active person should assume he and she will acquire genital HPV, at least once and often several times. Many (most?) can assume they will also be orally exposed and perhaps infected, since at any point in time, 25% or more of their potential sex partners can be assumed to be infected. When the partner is a CSW, the odds of exposure probably are even higher. However, young people can be immunized with Gardasil, the vaccine that protects against the 2 HPV types that cause most genital cancers as well as throat cancer (HPV-16 and 18) and genital warts (HPV-6 and 11).
To your questions:
HPV probably can be transmitted by performing oral sex on infected women, but probably with low efficiency, even if the woman has genital HPV. There are no precise data, but I would consider your encounter to be very low risk for oral infection.
HPV does not require symptoms for transmission. The virus can be transmitted whether or not warts or other abnormalities (e.g. an abnormal pap smear) are present.
How oral HPV is usually acquired is not certain. Oral sex is one obvious possibility, but some infections probably are from auto-inoculation, i.e. self infection in persons who already have a genital infection. There are over 100 HPV types, of which only 30-40 are primarily genital and transmitted sexually. The other 60-70 types may be transmitted by touching, kissing, and other methods. Future research may clarify these issues.
If you have an asymptomatic genital HPV infection, you certainly can transmit it to your sex partners by vaginal or anal sex, and perhaps if they perform oral sex on you. We do not know whether oral HPV can be transmitted or not. From what we know so far, oral to genital transmission probably is uncommon -- which is why I think your recent exposure is low risk.
Sexually active persons should not be overly worried about HPV. Like almost all sexually active people, you probably have been infected and will be again, and you may or may not currently be infected. Fortunately, the large majority of infections remain asymptomatic, even caused by the "high risk" (cancer causing) HPV types, clear up on their own, and never cause serious health problems. Women need pap smears to protect against cervical cancer; if genital or anal warts appear, see a health care professional for diagnosis and treatment; and all persons under 26 years old should consider being vaccinated. Then don't worry about it.
I hope this helps. Best wishes-- HHH, MD
It certainly does. I guess only one question that I am still interested in knowing is when would symptoms normally appear post encounter if they were to appear at all?
I was modifying my response while you were adding this comment; please re-read the reply above to make sure there's no confusion.
As I said, the only symptom you might notice would be warts, but oral warts are very rare. When warts appear, they typically show up 3-12 months after exposure.
And genital warts would be low probability anyway given oral to genital is uncommon?
By the way there are some dentists today who have equipment they use to check for oral hpv routinely- not sure if you're aware of that but interesting.
Yes, genital warts probably zero risk from receiving oral sex.
Yes, I am well aware that oral HPV testing is becoming available and used with increasing frequency. This is despite unknown benefits, and no recommendations from any responsible health agencies like CDC, health departments, or professional societies. The performance of the tests is unknown -- for example, a negative test result might be emotionally reassuring, but the available test may miss many (most?) infections. There aren't even any data what kind of specimen gives the best result. (Swab? If so, where from -- cheeks? gums? throat? all of these? Saliva? Gargle and spit?) And what is to be done with a positive result? No treatment is available, and the large majority of positive results probably are going to clear up without problems. Does having oral HPV matter, especially if not HPV-16? And most available tests don't actually distinguish all the HPV type(s) that may be present.
Until the answers to these uncertainties are known, I strongly recommend against oral HPV testing in asymptomatic people. And yes, I put my money where my mouth is. Without going into detail on my own history, suffice to say I had my day, sexually speaking. And I would not dream of being tested for HPV, genital, oral, or anywhere else.
Thank you for thorough responses and for your honesty as well.