Human papillomavirus (HPV) is a very common virus that can be spread through skin-to-skin contact. There are over 100 different strains of HPV, with some strains causing common warts on the hands and feet. Other strains are considered high-risk and can lead to certain cancers. Two strains in particular, HPV 16 and HPV 18, are responsible for most HPV-caused cancers.
Can HPV Be Transmitted Through Saliva?
Yes, HPV can potentially be transmitted through saliva. Saliva is one of the bodily fluids that contains traces of HPV when a person is infected. This means that activities where saliva is exchanged between partners, such as kissing, can potentially spread HPV between them.
That said, transmission of HPV through saliva is considered relatively rare compared to other forms of transmission. Genital skin-to-skin contact is by far the most common way that HPV spreads. But saliva still carries some risk of infection.
Evidence That HPV Can Spread Through Saliva
There are several key pieces of evidence that indicate HPV can be transmitted via saliva:
- HPV has been detected in saliva samples from infected individuals.
- HPV has been shown to be capable of infecting mouth and throat cells in laboratory studies.
- Partners of people with oral HPV infections acquire higher rates of oral HPV infections themselves.
- People with oral HPV show evidence of antibodies against the virus in their saliva.
Based on this evidence, researchers conclude that salivary transmission of HPV, while less common than genital transmission, does occur.
Risk Factors for Salivary Transmission
Certain factors may increase the risk of transmitting or acquiring HPV through saliva and oral contact:
- Open sores or wounds – damaged areas allow easier access for viruses
- Higher viral load – people recently infected have high amounts of virus present
- Deep kissing – prolonged contact increases exposure
- Oral sex – direct oral-genital contact spreads viruses more easily
People with active oral HPV infections likely pose the greatest transmission risk through their saliva. But even without symptoms, low levels of HPV may be present.
Does HPV Live in Saliva Permanently?
No, HPV does not appear to live permanently in people’s saliva once they are infected. The duration that HPV lingers in saliva can vary based on several factors:
- HPV type – Some strains clear faster than others
- Immune response – HPV may persist longer in immunocompromised individuals
- Site of infection – Oral HPV tends to clear faster than cervical HPV
- Age – HPV persists longer in older individuals
- Sex – Oral HPV persists longer in men than women
Among people with oral HPV infections, studies indicate the virus becomes undetectable in saliva in about 88% of people within one year. The rest clear the infection within two years. So even though HPV may persist in the short-term after initial infection, the virus does not appear to permanently inhabit saliva.
Can HPV Reactivate in Saliva?
Once an HPV infection has cleared, the virus generally does not reactivate or recur in the same location later on. However, some research indicates HPV reactivation is possible in rare cases, usually in people with weakened immune systems.
More research is needed to determine if reactivation in saliva can occur. But it appears unlikely based on current evidence. Once cleared from saliva, HPV seems to be gone for good in most people.
Ways to Reduce Salivary Transmission of HPV
While avoiding all skin-to-skin contact would be the only sure way to prevent HPV transmission through saliva, most people consider that unrealistic. Some more practical ways to lower risk include:
- Get vaccinated – HPV vaccines protect against strains most linked to cancers
- Limit open-mouth kissing – closed-mouth kissing is safer
- Use protection for oral sex – condoms or dental dams reduce contact with fluids
- Avoid mouths when warts present – direct contact spreads virus more easily
- Get tested regularly – allows early detection and treatment
Being open with partners about any HPV infections or symptoms can also reduce transmission risk. While salivary HPV represents a relatively small hazard, taking sensible precautions can help provide peace of mind.
HPV Transmission From Sharing Drinks
Drinking from the same cup, bottle, or can as someone with HPV theoretically could spread the virus through saliva left behind. However, this mode of transmission has not been documented.
Research suggests the risk of infection in this manner is extremely low for several reasons:
- Saliva contains low levels of HPV even in infected people
- HPV cannot survive long outside of the body
- Any traces of saliva get diluted in the drink
- Stomach acid kills viruses like HPV
So sharing drinks is not considered a significant risk factor for HPV infection compared to sexual routes of transmission. The same applies to other objects that may come in contact with someone’s saliva, like eating utensils.
Conclusion
HPV can be present in low levels in the saliva of infected individuals and transmit through activities like kissing. However, genital skin contact remains the most high-risk mode of transmission for HPV. The virus does not appear to permanently reside in saliva, and transmission from sharing drinks is negligible. While salivary transmission represents a small hazard, the risk can be reduced by vaccination, safer sexual practices, and routine testing.