STIs: Prevention, symptoms and when to seek medical advice
STIs are sexually transmitted infections. They are sometimes referred to as sexually transmitted diseases or STDs. This means they are most often - but not exclusively - spread by sexual intercourse. HIV, chlamydia, genital herpes, genital warts, gonorrhoea, syphilis, trichomoniasis and some forms of hepatitis are all STIs.
STIs used to be called venereal diseases or VD. They are among the most common contagious diseases.
Sexually transmitted infections (STIs) increased by 2% in England in 2011. The Health Protection Agency (HPA) said there were nearly 427,000 new cases, reversing a small decline in diagnoses seen the previous year.
You can get an STI by vaginal, anal or oral sex. You are at high risk if:
- You have more than one sex partner.
- You have sex with someone who has had many partners.
- You don't use a condom when having sex.
- You share needles when injecting intravenous drugs.
- You trade sex for money or drugs.
Sexually transmitted infections can be cured or managed if they are treated early. You may not realise you have an STI until it has damaged your reproductive organs (which could leave you with difficulties falling pregnant), your vision, your heart or other organs. Having an STI weakens the immune system and leaves you more vulnerable to other infections. Pelvic inflammatory disease (PID) is a complication of many STIs that can affect a woman’s fertility. If you pass an STI to your newborn child, the baby may suffer permanent harm.
What causes STIs?
Bacterial STIs include chlamydia, gonorrhoea and syphilis. Viral STIs include HIV, genital herpes, genital warts (HPV) and hepatitis B. Trichomoniasis is caused by a parasite.
The germs that cause STIs hide in semen, blood, vaginal secretions, and sometimes saliva. Most of the organisms are spread by vaginal, anal, or oral sex, but some, such as those that cause genital herpes and genital warts, are usually spread through skin contact. You can get hepatitis B by sharing personal items, such as toothbrushes or razors, with someone who has it.
Always avoid sex with anyone who has genital sores, a rash, discharge or other disease symptoms.
The only time unprotected sex is completely safe from infection is if you and your partner have sex only with each other, and if it's been at least six months since each of you tested negative for sexually transmitted infections (STIs). Otherwise you should:
- Use latex condoms every time you have sex. If you use a lubricant, make sure it's water-based. You should wear a condom throughout the sex act. Condoms are not 100% effective at preventing disease or pregnancy. However, they are extremely effective if used properly, so learn how to do this.
- Avoid sharing towels or underclothing.
- Wash before and after intercourse.
- Consider getting a vaccination for hepatitis B.
- If you have a problem with drug or alcohol abuse, get help. People who are drunk or using drugs often fail to have safe sex.
The only sure way to prevent STIs is by not having sex. It was once thought that using condoms with the spermicide nonoxynol-9 helped to prevent STIs by killing the organisms that can cause these diseases. But more recent research has shown that nonoxynol-9 also irritates a woman’s vagina and cervix, actually increasing the risk of an STI.
Subsequently, a number of manufacturers stopped making condoms lubricated with nonoxynol-9. According to current recommendations, there is no need for condom users to use spermicides as well.