Which elevated antibody titer indicates evidence of previous HSV-1 and HSV-2 infections?

The presence of elevated IgG antibody titers is indicative of past exposure to specific pathogens, such as HSV-1 and HSV-2, which are the viruses responsible for herpes simplex infections. IgG antibodies are typically produced in response to an infection and can remain in the body for an extended period, often for the lifetime of the individual. This persistence enables healthcare providers to determine whether a person has had a previous infection with these viruses.

In the context of HSV, a positive IgG titer suggests that the individual's immune system has recognized and responded to the herpes simplex virus, thereby providing evidence of previous infection. This is particularly useful for distinguishing between active and previous infections, as IgG levels remain elevated during the asymptomatic phases of the disease.

Other types of antibodies, such as IgA and IgE, serve different roles in the immune response and are not primarily used to indicate previous infections with HSV. IgM, on the other hand, typically indicates recent infections rather than past exposure, as it is the first antibody produced in response to an infection. Therefore, elevated IgG titers specifically indicate a history of HSV-1 and HSV-2 infections.