Herpes simplex
Herpes is very common. Worldwide rates of either HSV-1 or HSV-2 are between 60% and 95% in adults. Most people get HSV-1 when they are children. Since there is no cure for either HSV-1 or HSV-2, more people get it as they get older. Rates of HSV-1 are between 70% and 80% in poorer people and 40% to 60% in richer people. About 536 million people worldwide (16% of the population) were infected with HSV-2 as of 2003. It is more common among women and in developing countries. Most people with HSV-2 do not know that they are infected.