Sexually Transmitted Diseases/Saliva transmission?


Have there been studies of transmission of Hepatitus C or any other virus of concern through receiving oral sex. Isn't the virus present in saliva as well as other body fluids and blood?  And can't that virus enter the body through the penis?

Hello Carl,
The question you ask somewhat reminds me of "How many angels can dance on the head of a pin?"  In other words, it's a tough one to answer!  Studies of course have demonstrated the most efficient ways of a virus being spread but it's a bit more complicated and therefore essentially an unaswerable issue because it's not possible to account for all the variables:
1) viability and virulence (strength) of the virus in question (hepatitis C, HIV, etc.); and what is the absolute minimum number of viruses needed to cause transmission to another?
2) Vehicle by which virus is transmitted to someone else:  blood? semen? saliva? sweat? tears? breast milk? urine? feces?  And are one of these vehicle more conducive to spread?
3) How is the vehicle with proper virus load best able to be spread to the uninfected host? swollowing? a scratch in skin or mucous membrane? mere contact with mucous membrane like eye or nose or vagina or anus?
4) Does co-infection with another germ make it easier or more difficult for the virus to cause infection? Does such co-infection-- such as with chlamydia or gonorrhea-- increase the likelihood of bleeding to allow the virus, if pressent to better infect the host??
4) What is the role of the immune system in the uninfected host in fighting off the invading virus? Is this different based on the virulence (strength) of the virus? The numbers of virus (viral load)? The strength of the immune system?

Hepatitis C is essentially a blood borne virus, and it is less infectious than the hepatitis B virus. It is NOT thought to be transmissible through oral sex (although hepatitis B is) or carried by saliva. The virus can enter the body through the penis through a cut or scratch in the penis from friction, and an uncirc'd penis is easier to injure during sex.  

So the bottom line is that although possible, it is highly unlikely for a person to get hep C from any sexual activity that does not coincide with bleeding (even miniscule) from both partners.  

Hope this helps.

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Mark P. Behar


Almost any question or concern about gay men's health issues, sexually transmitted infections, abnormal Pap smears, anal cytology (anal "Pap smears"), etc. There is no such thing as “d/d free” or “clean” (free of infection), so why do so many of us deceive ourselves into thinking that some people are indeed totally free from a potentially infectious disease, like HIV, herpes, hepatitis, syphilis, chlamydia, warts, gonorrhea, etc., just because they say so? Clinical laboratory tests are not perfect, and having a “negative” or “nonreactive” test does not mean that a person is free from infection. Perhaps at the moment the test was taken, the person was uninfected; or, perhaps, the test wasn’t sensitive enough to detect presence of the infection. There is really no way that anyone can determine that they are truly “disease free,” and there are over a hundred of infectious conditions that can be spread without your knowing anything. Rather than trying to “pre-screen” or “serosort” a potential sex-mate with deceptive questions that are impossible to know by today’s technologies, a wiser option may be to consider everyone infected with something, and either use appropriate protective measures (“safer sex”), or accept the responsibility and consequences of possibly “catching” something from someone who’s hotter than expected (pun intended!). There is much research that supports the contention that an HIV positive person reliably taking HIV medications, and having an undetectable viral load, presents a lower risk for transmission of HIV than people who may think or say they are HIV negative, but are not. Food for thought!


Family Practice PA since 1981; Volunteer Clinician for Brady East STD (BESTD) Clinic, Milwaukee, since 1977; answered STD questions submitted to their web site. Professionally lectured at national and regional Physician Assistant and Nurse Practitioner conferences, and at national gay & lesbian health conferences on topics including HIV/AIDS, herpes, hepatitis, STDs, human papilloma virus (the cause of venereal warts), abnormal Pap smears, gay and lesbian health issues, among others.

Co-Founder, Lesbian, Bisexual, & Gay Physician Assistant Caucus of the American Academy of Physician Assistants, Inc.; American Academy of Physician Assistants; Wisconsin Academy of Physician Assistants; National Co-Chair (2012-16), National Association of Black and White Men Together: A Gay, Multiracial Organization for All People (NABWMT)

Journal of the American Academy of Physician Assistants (JAPA) Q Visions, Quarterly Newsletter of the NABWMT

Bachelor's of Arts, 1972 (University of Wisconsin, Milwaukee, WI) Graduate Credits Experimental Psychology, 1972-75 (Tulane University, New Orleans, LA) Physician Assistant, Bachelor's of Science, 1981 (George Washington University, Washington, DC); Masters in Physician Assistant Studies, 2000 (University of Nebraska Medical Center, Omaha, NE)

Awards and Honors
Colposcopy Recognition Award (CRA), the American Association of Colposcopy and Cervical Pathology; Distinguished Fellow, Clinical Preceptor, American Academy of Physician Assistants; Fellow, Wisconsin Academy of Physician Assistants

Past/Present Clients
Brady East STD Clinic, Milwaukee, WI Milwaukee Health Services, Inc. (Martin Luther King Heritage Health Center), Dept. of Family Medicine and Early Intervention Program for HIV Infected Persons

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