If you have herpes simplex virus type 1 (HSV-1) and you have a cold sore or fever blister on or around your mouth, you should avoid kissing your baby or anyone else, especially newborns, infants, and anyone with a weakened immune system.
Newborns, in particular, are at a higher risk of developing serious health problems if they are exposed to the herpes simplex virus. The virus can be spread to a baby through direct contact with a cold sore, and it can lead to a potentially life-threatening condition called neonatal herpes.
To reduce the risk of spreading the virus to your baby, it is important to take precautions such as washing your hands frequently and avoiding close contact with your baby until the cold sore has healed completely. You may also want to speak with your healthcare provider about antiviral medications that can help prevent outbreaks and reduce the risk of transmission.