More than 30 bacteria, viruses and parasites are known to spread through sexual contact. Eight of these pathogens have the highest incidence of disease. Of the eight infections, four are currently curable, namely syphilis, gonorrhea, chlamydiaand trichomoniasis. The other four are incurable viral infections, namely hepatitis B, herpes simplex virus, HIVand human papillomavirus. Symptoms or diseases caused by these incurable viral infections can be alleviated or ameliorated by treatment.
Some sexually transmitted infections can be transmitted through sexual contact with skin contact. Microorganisms that cause sexually transmitted infections can also be transmitted through pathways other than sexual contact, such as shared blood products and tissue transplants. Many sexually transmitted infections, including chlamydia, gonorrhea, hepatitis B, HIV and syphilis, can also be passed from mother to baby during pregnancyand childbirth.
Sexually transmitted infections can be free of any obvious symptoms of the disease. Common symptoms of sexually transmitted diseases are vaginal discharge, male urethral secretions, genital ulcers and abdominal pain.