In many states it is a criminal offense to intentionally or recklessly transmit a sexually transmitted disease (STD or venereal disease) to another person. Examples of such diseases include HIV/AIDS, syphilis, gonorrhea, chlamydia, genital herpes, human papillomavirus (HPV), genital warts, and hepatitis B.

Laws vary from state to state, and in some states these laws include other infectious or communicable diseases. In some states there is a specific criminal offense for transmission of sexually transmitted or communicable diseases, and in other states criminal prosecutors charge the defendant with a more general crime like assault.

Laws regarding criminal liability for the intentional or reckless transmission of sexual or other infectious or communicable diseases are generally located in a state’s statutes—often in the penal or criminal code, or the health and safety code.

A person who negligently transmits a sexually transmitted disease to another person through sexual contact—without informing the other person of the offender’s infection before the sexual contact—may also be subject to civil liability for money damages in a lawsuit.

In Connecticut, the transmission of a sexually transmitted disease (STD) can lead to criminal charges under certain circumstances. Connecticut General Statutes Section 53a-65 defines 'serious physical injury' to include 'the impairment of physical condition or pain which ... involves ... a protracted loss or impairment of the function of any bodily organ,' which can be interpreted to include the transmission of an STD. Additionally, under Section 19a-343, any person who knows that they are infected with an STD and engages in behavior that is likely to transmit the disease to another person may be guilty of a Class C misdemeanor. This includes diseases such as HIV/AIDS, syphilis, gonorrhea, chlamydia, genital herpes, HPV, genital warts, and hepatitis B. Beyond criminal liability, individuals may also face civil lawsuits for negligently transmitting an STD without informing their partner prior to sexual contact, potentially resulting in monetary damages.