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 Wisconsin, the intentional or reckless transmission of a sexually transmitted disease (STD) can lead to criminal charges. Wisconsin Statute § 939.22(50) defines a 'sexually transmitted disease' for the purposes of criminal law. Under Wisconsin Statute § 940.225(3), a person who has an STD and engages in sexual activity without informing their partner of their condition can be charged with reckless endangerment or other related offenses. This statute is part of the state's penal code, which addresses sexual assault and the transmission of diseases. Additionally, Wisconsin law allows for civil liability, meaning that a person who negligently transmits an STD without disclosing their infection to their sexual partner before contact can be sued for monetary damages. The civil liability is separate from the criminal charges and is pursued through a civil lawsuit.