People infected with syphilis at the primary stage normally have no symptoms. In case they do, a single sore or multiple sores can be found.

This virus can cause genital warts and some cancers. There are more than 100 strains and approximately 40 strains can be sexually transmitted.

Hepatitis C virus is a virus that can cause damage to liver and often lead to chronic hepatitis C which can develop into a serious disease such as cirrhosis and cancer.

Hepatitis B Virus is a virus that causes damage to liver. Chronic hepatitis B can develop into a serious disease resulting cirrhosis and cancer.

The infection is through contacting with stools (feces) that contain the virus, which can also be contaminated in food, water or surfaces. In general, it tends to be more severe in adolescents and adults but can be resolved without any treatment.