Cold sores are highly contagious from the time the first symptom appears. This is usually 1–2 days before the sore becomes visible. Sores remain highly contagious until the skin completely heals. This can take up to 15 days.

How long is HSV-1 contagious after outbreak?

Cold sores are typically contagious for up to 15 days. You need to wait until all your cold sore symptoms have cleared – including the blister and any scabbing – to reach the point when cold sores are not contagious anymore.

Should you worry about HSV-1?

Bottom line: Theres no need to freak out about positive results. There are two types of herpes simplex virus, which can cause painful sores on the mouth and/or genitals. HSV-1 primarily causes sores on the mouth.