Syphilis

Syphilis is caused by a bacteria through sexual contact with an infected person. Transmission can also occur through blood transfusion if the donor is in the early stages of the disease, or by sharing needles with an infected person. Pregnant women can pass the infection to their unborn babies. Symptoms are progressive, beginning with a painless rash or ulcer, headache, nausea, and weight loss; progressing to central nervous system damage, heart damage, and death, if left untreated.