There are tests to see if you are infected with the virus, but they rely on the immunity you develop to the virus and so take several weeks to run, and these tests are available mainly in research laboratories. It usually takes 3-6 days after exposure to become infected. Typically a person with herpangina has a fever and a very sore throat, and possibly a sore mouth as well. These are caused by the virus, unlike true canker sores.
Milk seems to be fairly soothing for some patients.
The pain and fever will make you quite uncomfortable while you have the sores. The biggest problem with herpangina, though, is that the pain may make it difficult for you to drink enough to avoid becoming dehydrated . Although you get dehydrated in a different way, though, the signs of dehydration are the same, and you should watch for these. In some cases, however, there are medicines we can give to soothe the pain. There are also some prescription medicines that can be swished around the mouth to help soothe the pain enough for you to drink and maybe even to eat.