Basically it is an infection, so you run a high fever, have sore skin, feel shivery and cold/hot and feel weak and off-colour. Obviously, you don’t have the facial/nasal symptoms of flu, or the sore throat.

Those symptoms started for me about four days after exposure.

To anyone who thinks herpes only produces localised symptoms and you don’t get sick with it:

When you first catch herpes your body is fighting a new infection, so it is normal to have symptoms of that infection – such as a fever. It doesn’t happen to everyone, but it happens to a high proportion of people catching herpes for the first time. Symptoms are usually described as ‘flu-like’ and can be severe.

Colds and herpes: yes, a cold can trigger a herpes outbreak. And recurrent outbreaks, or cold sores, do not usually cause flu-like symptoms or a fever. But recurrent herpes CAN occasionally give you a fever etc. It is an infection, and if your body struggles to fight it you will have a fever. This can happen to people with cold sores or genital herpes. I have had to go to the emergency doctor with a high fever due to a recurrent herpes outbreak in the past. That happened a year after my primary outbreak; these days, herpes doesn’t make me sick any more.

The fever isn’t always due to a cold – it can be caused by the herpes virus itself, especially in new infections.