Things you need to know about sexually transmitted infections

Sexually transmitted infections (STIs) are also known as sexually transmitted diseases or venereal diseases. STIs are spread mostly through unprotected sexual intercourse, ie sexual intercourse without a condom.

STIs are caused by bacteria, viruses, fungi or parasites that can cause a variety of symptoms and problems. Most STIs in humans primarily affect genitals. With oral stimulation, pathogens can also be spread in the pharynx. Other diseases, such as HIV, hepatitis B and syphilis can affect your whole body. Since STIs often progress without symptoms, you should consult a doctor if you have even the slightest reason for concern.

Some infections are also spread through blood, skin-to-skin contact or from mother to child during pregnancy, childbirth or breastfeeding. Some STIs can be cured, others cannot. Undiagnosed and untreated STIs can lead to long-term discomfort and can have life-threatening consequences.

Unprotected sexual intercourse with an infected person is the most common way STIs are transmitted. People can become infected through vaginal, oral and anal sex. The inner surface of the human vagina, anus, urethra and mouth is covered with mucous membranes on which micro-organisms (bacteria, viruses, protozoa) that cause STIs live and reproduce. Please note that many birth control products, like contraceptive pills or patches, do not protect you from STIs!

During unprotected sexual intercourse, these infectious agents can spread from one person’s mucous membranes to the other’s. It makes no difference whether the sexual partners are of the opposite or the same sex – everyone is at risk of infection if they have unprotected sex.

STI transmission

  • STIs are most commonly spread through unprotected sexual intercourse.
  • Wound-transmitted infections can also spread by skin-to-skin contact.
  • HIV and hepatitis C are transmitted by blood contact, for example by sharing needles.
  • Most STIs can be passed from mother to child during pregnancy and childbirth, and may harm the baby. For example, a mother who is infected with gonorrhoea conjunctivitis can infect her newborn, leading to the child’s loss of sight unless preventative treatment is provided. In Estonia, women are screened during pregnancy for syphilis, HIV and hepatitis B, as well as other STIs. If you have had unprotected sex or are pregnant, it is important to inform your doctor about any complaints you or your partner may have. Tests and treatment can be carried out if necessary, in order to protect the health of yourself and your child.
  • Scabies and pubic lice are spread through close physical contact and bed linen.

How can I protect myself from STIs?

The best protection against STIs is using protection during sexual intercourse. Practise safe sex and do not let your partner’s semen, blood or vaginal fluids enter your body. The fewer sexual partners you have, the lower the chance of getting infected. Some STIs can be prevented by vaccination.

How do I know if I have an STI?

Pictures and descriptions alone do not help you determine whether you or your partner have an STI, as people may have different symptoms or none at all. In the case of some STIs, the symptoms come and go. This does not mean that the infection has receded.

What should I do if I have been diagnosed with an STI?

If you are diagnosed with an STI you need to inform your sexual partners, so that they too can get checked and treated promptly, if necessary. Some STIs, most notably chlamydia and gonorrhoea, can progress without symptoms and therefore you may not be aware that you are infected! But even symptomless STIs can cause long-term health problems. Regardless of whether symptoms are present or not, unprotected sexual intercourse can lead to the infection of another person or to becoming infected yourself.

If you have any of the symptoms mentioned, contact your doctor (family physician, gynaecologist, urologist, dermatovenerologist). Testing is the only way to find out if you are infected.

As the disease will not go away on its own, timely medical treatment is essential. Nowadays, most STIs have effective treatments that help prevent many future problems.

All STIs (including HIV) are preventable. 

Watch this video to take a look at HIV testing.

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