In industrialised countries, there has been a drastic decrease in the number of reported cases of syphilis, gonorrhoea, and tropical sexually transmitted diseases (STD) since the introduction of antibiotics in the 1950s, whereas among the general population of non-industrialised countries, the number of cases of these diseases has remained extremely high. The World Health Organization has estimated that, worldwide, 333,000,000 new cases of curable STD occur every year and that 90% of these cases come from non-industrialised countries. Moreover, viral STD, such as genital herpes, condyloma, hepatitis B infection, and HIV-1 infection, represent an even greater problem in that they are not curable. STD are also a cause of serious complications in the genital and reproductive tracts of both genders, and curing these complications requires substantial economic resources.