Rise of STIs means safer sex is so vital.
* ast year there was a 2% rise in the number of sexually transmitted infections - that seems a low figure but it's worrying because it reverses the trend seen in 2010 when there was a drop in STIs.
The most dramatic rise was in cases of gonorrhoea, which increased by 25%, with syphilis up 10% and herpes 5%.
The biggest rise was among men having sex with men while heterosexuals rates remained highest among young adults aged 15 to 24.
The Health Protection Agency had expected some increase because of improvements in testing, but not on the scale revealed by the stats.
It says the reason for this explosion is that too many people are having unsafe sex. They contract STIs, pass them on to others, spreading not just the infections but the risk of long-term problems.
It's essential, believes the HPA, to improve awareness of the need to practise safe sex. We should all be concerned by the increasing prevalence of gonorrhoea because it is becoming more and more resistant to existing drugs and we have no new drugs on the way.
Treatment failures with standard medication are already starting to emerge with one in France and another in Spain in the last few months.
Gonorrhoea can be nasty for both men and women in the short and long-term. The "clap" is caused by bacterium neisseria gonorrhoeae and can be transmitted through genital, oral and anal sex.
An infected woman can also pass it on to her baby.
One of its main problems is that there'll be no symptoms in two thirds of infected women but there can be a vaginal discharge and severe pain on passing urine.
A baby acquiring gonorrhoea from its mother will have severe inflammation of one or both eyes.
And it can affect other parts of the body: in men, inflammation of the prostate gland and the testicles, damaging fertility, and in women it causes pelvic inflammatory disease, affecting the Fallopian tubes, leading to possible ectopic pregnancy and infertility. Bacteria in the bloodstream can cause arthritis and inflammation of the heart and the brain.
Sex is only safe when you're monogamous. Avoiding multiple partners is crucial. But the ultimate weapon in protecting yourself and your partner is a condom. Insist on their use before engaging in sex.