Sexually transmitted infections (STIs) are infections that are spread primarily through person-to-person sexual contact. There are more than 30 different sexually transmissible bacteria, viruses and parasites. Several, in particular HIV and syphilis, can also be transmitted from mother to child during pregnancy and childbirth, and through blood products and tissue transfer. Some of the commonest sexually transmitted pathogens can be divided into those caused by bacteria, viruses and parasites. Cytomegalovirus (causes inflammation in a number of organs including the brain, the eye, and the bowel).
Trichomonas vaginalis (causes vaginal trichomoniasis) Candida albicans (causes vulvovaginitis in women; inflammation of the glans penis and foreskin [balano-posthitis] in men).
Sexually Transmitted Infections (STIs) as a major public health issue
In developing countries, STIs and their complications rank in the top five disease categories for which adults seek health care. Infection with STIs can lead to acute symptoms, chronic infection and serious delayed consequences such as infertility, ectopic pregnancy, cervical cancer and the untimely death of infants and adults.
STIs and prevention of serious complications in women
STIs are the main preventable cause of infertility, particularly in women. Between 10% and 40% of women with untreated chlamydial infection develop symptomatic pelvic inflammatory disease. Post-infection tubal damage is responsible for 30% to 40% of cases of female infertility. Furthermore, women who have had pelvic inflammatory disease are 6 to 10 times more likely to develop an ectopic (tubal) pregnancy than those who have not, and 40% to 50% of ectopic pregnancies can be attributed to previous pelvic inflammatory disease. Infection with certain types of the human papillomavirus can lead to the development of genital cancers, particularly cervical cancer in women.
STIs and adverse outcomes of pregnancy
Untreated sexually transmitted infections are associated with congenital and perinatal infections in neonates, particularly in the areas where rates of infection remain high.
In pregnant women with untreated early syphilis, 25% of pregnancies result in stillbirth and 14% in neonatal death – an overall perinatal mortality of about 40%. Syphilis prevalence in pregnant women in Africa, for example, ranges from 4% to 15%. Up to 35% of pregnancies among women with untreated gonococcal infection result in spontaneous abortions and premature deliveries, and up to 10% in perinatal deaths. In the absence of prophylaxis, 30% to 50% of infants born to mothers with untreated gonorrhoea and up to 30% of infants born to mothers with untreated chlamydial infection will develop a serious eye infection (ophthalmia neonatorum), which can lead to blindness if not treated early. It is estimated that, worldwide, between 1000 and 4000 newborn babies become blind every year because of this condition.
STIs and HIV
The presence of an untreated ulcerative or non-ulcerative (those STIs which cause ulcers or those which do not) infection increases the risk of both acquisition and transmission of HIV by a factor of up to 10. Thus, prompt treatment for STIs is important to reduce the risk of HIV infection. Controlling STIs is important for preventing HIV in people at high risk, as well as in the general population.
Prevention of STIs
The most effective means to avoid becoming infected with or transmitting a sexually transmitted infection is to abstain from sexual intercourse (i.e., oral, vaginal, or anal sex) or to have sexual intercourse only within a long-term, mutually monogamous relationship with an uninfected partner. Male latex condoms, when used consistently and correctly, are highly effective in reducing the transmission of HIV and other sexually transmitted infections, including gonorrhoea, chlamydial infection and trichomoniasis.
STIs without symptoms
Some sexually transmitted infections often exist without symptoms. For example, up to 70% of women and a significant proportion of men with gonococcal and/or chlamydial infections may experience no symptoms at all. Both symptomatic and asymptomatic infections can lead to the development of serious complications.
Most STIs are silent or may present with symptoms some time after the infection occurred. This makes it impossible to tell if you, a partner or potential partner is carrying a silent STI. The most reliable way of avoiding an STI is to always practice safer sex and when embarking on a new relationship to consider screening for STIs before embarking on a long-term mutually monogamous relationship with a partner who has been tested and is known to be uninfected.
It is now possible to screen for many of the common STIs based on an internet ordered home sample urine test or blood test kit using a laboratory technique called PCR with results via confidential text or email.
Urine Test Kits will screen for Chlamydia, Gonorrhoea, Mycoplasma, Ureaplasma, Gardnerella, Trichomonas, Herpes Simplex I/II
Blood Test Kits will screen for HIV, Hepatitis B & C and Syphylis
The “Window Period”
Testing too quickly after you have run a risk of infection may result in a false negative (no infection found) result being given to you as infections may not show up on the test for some weeks. Although you should contact a healthcare provider as soon as possible if you have been at risk, when performing laboratory testing for Chlamydia and Gonorrhoea for example it is recommended that you additionally test two weeks after your risk (sex with the person you are worried about). When testing for HIV and Syphilis (blood tests) you should additionally test at least 12 weeks after your risk. If there is a specific incident which put you may need to have your tests repeated to ensure that you do not miss a possible infection.
Signs and Symptoms of STIs
The following signs and symptoms may be present after an STI but remember most are silent.
Neonatal eye infections (conjunctivitis of the newborn)
How can I find out about testing and treatment for an STI?
If you are worried about or think you might you might have an STI, have recently been exposed to the risk of an STI or wish to discuss screening, testing and treatment you should do so now as early advice, testing and treatment is important.
NHS:Testing is free on the NHS from genitourinary medicine clinics, sexual health clinics, many Family Planning Association and contraception clinics, your GP and pharmacies. You can find an clinic to help with STIs by phoning directory enquiries and asking for genitourinary medicine, sexually transmitted disease or venereal disease or locate one using our NHS Genitourinary Medicine Clinic page in the Sexual Health Section of our website. You can also contact NHS Direct on 0845 4647.
PRIVATE:You can have confidential private testing and treatment or screening via an internet ordered home sample urine test or blood test kit. Telephone 0345 2303386 or use the Confidential Text Service 07786202070
Further Information on Sexually Transmitted Diseases in the UK
Further information and help about issues relating to Sexually Transmitted Infections can be obtained from the following sites:
AVERT - International AIDS Charity
British Association for Sexual Health and HIV
Family Planning Association
Terrence Higgins Trust