People who recklessly infect their partners with sexually transmitted diseases could soon be jailed.
In a crackdown by the Crown Prosecution Service, adults with diseases such as chlamydia, syphilis and herpes will be liable for arrest and prosecution unless they warn their lovers about their condition.
Those who pass on hepatitis, gonorrhea and other sexual infections will also be targeted, as will people who transmit the HIV/Aids virus.
Wearing a condom will not remove the risk of prosecution and offenders could be brought to justice even if their victim is unwilling to testify, because of the potential danger to others in the future.
Until now, CPS policy has been to concentrate on bringing cases against those who pass on the HIV/Aids virus.
The crackdown could potentially result in hundreds of people being put on trial.
Sir Ken Macdonald, the Director of Public Prosecutions, is due to unveil full details of the new policy next month.
This is despite fears raised by sexual health campaigners and doctors that the prosecutions drive could cause some infected people to shun treatment.
Before a prosecution is mounted, the CPS will have to assess whether a defendant knew about their infection, their level of knowledge about its potential impact and whether they told their lover.
Cases where a person knows of their infection but fails to reveal it, leading to their partner contracting the disease, are likely to be classed as examples of 'reckless' transmission that can be prosecuted.
The charge in such cases will be one of inflicting grievous bodily harm, an offence which carries a maximum penalty of five years in jail for each person infected.
In more serious cases, where there is clear evidence that transmission was intentional, a more severe charge carrying a maximum life sentence could be brought.
However, the difficulty of legally proving deliberate transmission means that most offenders are likely to be prosecuted on the lesser charge.
Crucially, it will not be a defence to argue that a victim who has unprotected sex should have been aware of the risk of infection.
Instead, the onus will be on the infected person to make clear the danger before sex occurs. Similarly, a defendant will not be exempt from prosecution if they wear a condom - particularly if it was not used properly throughout the sexual encounter.
However, proper use of a condom will be a factor in deciding the seriousness of the offence and whether to bring a case.
Offenders will also be brought to trial even when their victim declines to testify if it is judged to be in the public interest by preventing any future lovers being infected.
All that will be required in such cases will be medical evidence that the infection has been passed on and proof that the accused person recklessly or deliberately failed to tell their partner about it.
About 10 people have been convicted of the reckless transmission of HIV, including one gay man and one woman.
The first person to be jailed in England was Mohammed Dica, a Kenyan living in Mitcham, who received a four-and-a-half-year sentence after being convicted of causing grievous bodily harm in 2003.
Some doctors argue that criminalising transmission of sexual infections could deter people from seeking a test because they may think confirmation will put them at greater risk of prosecution.