Sexual health is important to everybody, but is especially important if you have HIV because sexually transmitted infections (often shortened to STIs) can not only cause illness, but increase the chances of you passing on HIV during unprotected sex, even if you have an undetectable viral load in your blood.

Although sexually transmitted infections can seem minor, they can and do cause unpleasant symptoms. If left untreated, some can cause severe health problems. In the very long-term, some can cause irreversible damage and, in extreme cases, be fatal.

Some sexually transmitted viral infections, such as herpes simplex virus -2 (HSV-2, normally just called herpes) cannot be cured, though symptoms can be controlled. Hepatitis B is very easy to pass on during sex, and hepatitis A and C can also be transmitted during certain types of sex. Hepatitis A, B and C can make you ill in the short-term and hepatitis B and C can cause long-term liver disease, which can even be fatal. Hepatitis B and C can make HIV harder to treat.

A small number of people have been reinfected (sometimes also called superinfected) with different or drug-resistant strains of HIV.

Having good sexual health also includes feeling comfortable with your sexuality, and the kinds of sex you are having and who with.