By Dr Ananya Mandal, MD
The herpes simplex virus is spread through skin-to-skin or sexual contact with an individual who is infected with the virus.
Unprotected vaginal, rectal or oral intercourse may all lead to the transmission of herpes simplex infection from an infected person. Skin-to-skin contact is more likely to lead to transmission of the virus on direct contact with an infected lesion or if microscopic abrasions or cuts are present, allowing the virus access to the body.
It is less certain whether sharing towels, utensils and cutlery carries a risk of transmission but avoiding contact with such items is advised if a person is known to be having an outbreak of symptoms.
The lesion seen in herpes contains a clear fluid in which the infective viral particles are present. The body develops antibodies to the herpes simplex virus within weeks after acquiring the infection, and these antibodies can be detected on laboratory investigations. In a person who has transmitted oral HSV 1 infection, antibodies may take around 6 weeks to develop.
In a person with herpes infection, the shedding of the virus may occur even when they have no symptoms, meaning a partner may be completely unaware of any risk of infection. This presents challenges in managing, controlling and preventing the tranmsission of herpes.
In nearly half of individuals infected with the virus who do not have symptoms, shedding of the virus can occur more than a week before or after symptoms present. In addition, if other infections are present, the risk of transmission in the absence of overt symptoms is higher still.
Reviewed by Sally Robertson, BSc