Different Types of STIs
Viruses, bacteria or parasites can cause sexually transmitted infections. The most common STIs, however, tend to be bacterial and include infections like gonorrhoea and chlamydia. Viral STIs are also fairly common, especially in the form of genital warts and genital herpes. The majority of STIs are curable and if they can't be cured they can be effectively managed with the help of anti-viral or antiretroviral treatments. However, when it comes to STIs, prevention is always better than cure.
These types of infections develop as the result of bacteria that is passed from person to person during sexual contact. They tend to affect areas such as the vagina, urethra, cervix, rectum, mouth and throat of the person that's been infected, but can also spread to areas that are similarly mucosal, such as the eyes. Some more serious bacteria like Treponema pallidum, that causes syphilis, can eventually start to spread to the central nervous system if it's not treated in time.
It's very easy for bacterial STIs to spread, because they aren't likely to cause symptoms. This means that people may not realise they are infected and so will be at a high risk of passing on the STI to any new partner.Common bacterial STIs are:
- Gonorrhoea (caused by neisseria gonorrhoea)
- Chlamydia (caused by chlamydia trachomatis)
- Syphilis (caused by Treponema pallidum)
- Bacterial vaginosis
- Mycoplasma genitalium
- Non-specific urethritis
Most bacterial STIs can be treated with the help of a single course of antibiotics, however the cause of the infection will have to be established with the help of an STI test first. Syphilis and gonorrhoea tend to be more difficult to treat, particularly syphilis, which can require hospitalisation.
Viral STIs are infections that are caused by viruses. These viruses mainly pass via sexual intercourse. This may be vaginal, anal or oral, but doesn't just require bodily fluids to pass from one partner to another. Most viral STIs can never be fully cured, but they can be managed to the point where they are hardly noticeable.
Although the most common types of viral infections like genital herpes and warts aren't likely to be dangerous, HIV has the potential to cause very serious complications. Just like bacterial STIs, viral STIs might not be noticeable at first, but genital herpes and warts may start causing visible symptoms such as wart-like mounds in and around the genital area and anus (genital warts) or a blister-like rash accompanied by discomfort (genital herpes). Genital herpes can cause sporadic outbreaks that go away after a while.Common viral STIs include:
- Genital herpes (caused by the herpes simplex virus type II)
- Genital warts (caused by the human papilloma virus HPV)
- HIV (caused by the human immunodeficiency virus)
Genital herpes is generally treated as and when an outbreak happens with the help of antiviral medicines and creams, however, if outbreaks frequently recur, an antiviral medication can be administered as a preventative technique. Genital warts are mostly treated with antiviral creams until the external traces of the infection go away. HIV requires more long-term management with the help of antiretroviral treatments.
Parasitic STIs are also passed through direct sexual contact or sometimes simply though direct contact with the genital area affected by the parasite. They tend to be dependent on a human host to survive and are organisms that are so small that an infestation may not become noticeable until much later. Parasites aren't likely to be dangerous and are more likely to cause discomfort, although trichomonas vaginalis can affect long-term reproductive health.Common parasitic STIs include:
- Trichomonas vaginalis (caused by the Trichomoniasis parasite)
- Crabs (caused by the Pediculosis pubis louse)
- Scabies (caused by the Sarcoptes scabiei mites)
Parasitic STIs can also be treated with the help of oral antibiotics (trichomonas vaginalis) or creams (scabies) however, crabs is usually treated by shaving the genital area and/or applying insecticide cream, lotions or shampoos.