This is one of the most common STD's and about 20,000 cases of it are seen in GUM clinics every year. There are two strains of the virus, the second leads to genital herpes. Within a week of contact with an infected partner a red, painful rash will occur on the genital areas. The rash will eventually blister and then burst, producing fluid. This is the most infectious stage. You will be infectious until the rash has gone. During this stage you will feel feverish, unwell and exhausted. Lymph glands in the groin will also become swollen and sore. This STD is treatable but there is no cure. Symptoms appear within 1 week of infection.