Which sexually transmitted disease is caused by a spirochaete and passes through primary, secondary and tertiary stages?

Explanation

Syphilis is caused by the spiral bacterium Treponema pallidum, beginning as a painless ulcer, then a body wide rash, then a long latent period, and finally damage to the heart, blood vessels and nervous system years later. This staged course is unique among the common sexually transmitted infections. Gonorrhoea is also bacterial but does not follow this pattern, and herpes and candidiasis are viral and fungal respectively.