… makes it less likely that you will pass the infection on to your sex partner(s).
Oral herpes (such as cold sores or fever blisters on or around the mouth) is usually caused by HSV-1. Most people are infected with HSV-1 during childhood from non-sexual contact. For example, people can get infected from a kiss from a relative or friend with oral herpes. More than half of the population in the U.S. has HSV-1, even if they don’t show any signs or symptoms. HSV-1 can also be spread from the mouth to the genitals through oral sex. This is why some cases of genital herpes are caused by HSV-1.
Using condoms may help lower this risk but it will not get rid of the risk completely. Having sores or other symptoms of herpes can increase your risk of spreading the disease. Even if you do not have any symptoms, you can still infect your sex partners.