Herpes Simplex Virus Type 1 (HSV-1) is a widespread viral infection that causes painful blisters, commonly known as cold sores or fever blisters. It is possible to contract HSV-1 through kissing. This virus is remarkably common, affecting billions of people globally; for instance, an estimated 3.8 billion people under the age of 50, or 64% of the global population, had HSV-1 infection in 2020. In the United States, about 50% to 80% of adults carry the virus that causes oral herpes.
How HSV-1 Spreads
HSV-1 primarily spreads through direct contact with infected skin or mucous membranes, particularly through saliva or the fluid from sores. Kissing is a common method of transmission for oral HSV-1, as it involves direct oral-to-oral contact. This contact can occur when an infected person has active cold sores or even when no visible lesions are present, a phenomenon known as asymptomatic shedding.
While the risk of transmission is highest during an active outbreak when blisters or sores are present, the virus can still be shed and spread from seemingly normal skin or saliva. Asymptomatic shedding means the virus is replicating and present on the skin surface without causing any noticeable symptoms. Studies suggest that at least 70% of the population may shed HSV-1 asymptomatically at least once a month. Besides kissing, sharing personal items like eating utensils, drinking glasses, lip balm, or razors can also facilitate the spread of HSV-1.
Symptoms of Oral Herpes
Oral HSV-1 infection often manifests as cold sores or fever blisters, which typically appear on or around the lips, nose, or inside the mouth. An outbreak usually begins with a tingling, itching, or burning sensation in the affected area, often a day before blisters appear. Small, fluid-filled blisters then develop and may cluster together.
These blisters eventually break open, leading to shallow, painful sores that may ooze fluid. The sores then crust over, forming a scab that heals, typically within two to three weeks without leaving a scar. Many people infected with HSV-1 have very mild or no symptoms, making them unaware they carry the virus.
Reducing Transmission Risk
To minimize the risk of transmitting or acquiring HSV-1, avoid direct skin-to-skin contact, including kissing, during an active oral herpes outbreak. Also avoid sharing personal items that come into contact with saliva, such as eating utensils, drinking glasses, or lip balm. Practicing good hand hygiene, especially after touching a cold sore, can further reduce the spread of the virus.
Antiviral medications can help manage outbreaks by reducing their severity and duration. When taken daily, these medications can also reduce the frequency of outbreaks and may lessen viral shedding, potentially lowering the risk of transmission. However, even with these measures, HSV-1 can still be transmitted, particularly during asymptomatic shedding.