That you are getting the white spot on your lips especially when the body is stressed, for example during a febrile episode (fever), it is suggestive of a herpes
Occasionally, these herpes infections (also referred to as cold sores) on the lips occur when there is a chest infection
It is nothing to worry about as aciclovir
) usually prevents the virus from replicating and the cod sores disappear.
Apply the Zovirax and see what happens. If you are not sure, you can always see your doctor.