Sexually transmitted diseases
Written by Dr Jeni Worden, GP and Dr Flemming Andersen, specialist
What is a sexually transmitted disease (STD)?
An STD is an illness that is spread through sexual contact.
How can sexually transmitted diseases be avoided?
- The less sexual partners a person has, the lower the risk of infection.
- Most sexually transmitted diseases can be avoided to a large extent by practicing safe sex (eg using condoms).
- Most sexually transmitted diseases can be cured if they are diagnosed and treated in their early stages.
The most common diseases and their symptoms are described below.
Chlamydia
Chlamydia is the most common and fastest spreading sexually transmitted disease in the UK. It stems from a bacterium, Chlamydia trachomatis.
Women diagnosed with Chlamydia can also infect their newborn infant during delivery. Symptoms usually appear approximately 7 to 21 days after infection and differ for men, women and children.
Symptoms in men:
- inflammation of the urethra (the bladder duct within the penis)
- stinging feeling when passing water
- clear discharge from penis and possible itchiness around the opening
- pain or tenderness in the testicles.
Symptoms in women:
- stinging feeling when passing water
- unusual vaginal discharge
- pain caused by pelvic inflammation (pelvic inflammatory disease)
- pain during intercourse
- in some cases, bleeding between periods.
Symptoms in infants:
- inflammation of the eye (conjunctivitis) at birth
- problems breathing
- premature birth
- in rarer instances, pneumonia.
One of the most common ways of testing for Chlamydia is for the GP to collect a cell sample from the infected area (cervix or penis) with a cotton swab. This is then sent to a laboratory for evaluation. In the absence of a firm diagnosis, you may be referred to a specialist genitourinary clinic for further testing. Treatment consists of antibiotics, and should also be given to the patient's partner. A further swab is recommended once treatment has ended to check whether the infection has cleared.
For more information, read the factsheet on chlamydia.
Gonorrhoea
Gonorrhoea is caused by Neisseria gonorrhoeae, a bacteria that grows and multiplies quickly in moist, warm areas of the body such as the cervix, urethra, mouth, or rectum. In women, the cervix is the most common site of infection. However, the disease can also spread to the uterus (womb) and fallopian tubes, causing pelvic inflammatory disease leading to infertility. Gonorrhoea is most commonly spread during genital contact, but can also be passed from the genitals of one partner to the throat of the other during oral sex. Gonorrhoea of the rectum can occur in people who practice anal intercourse.
In pregnant women, gonorrhoea can be passed from an infected woman to her newborn infant during delivery if left untreated.
The early symptoms of gonorrhoea are often mild, and many women who are infected have no visible symptoms of the disease. If symptoms of gonorrhoea develop, they usually appear within 2 to 10 days after sexual contact with an infected partner, although a small percentage of patients may be infected for several months without showing symptoms.
Symptoms in women include:
- painful, burning sensation when urinating
- yellowish or bloody discharge from the vagina
- bleeding between periods
- abdominal pain.
. Men are more likely to show symptoms than women. Some of the symptoms in men include:
- burning sensation during urination
- yellowish-white discharge from the penis.
Other symptoms affecting the rectal area include itching, discharge and sometimes painful bowel movements.
A diagnosis is made through detection of bacteria in samples taken from the urethra, cervix, throat or rectum. The condition is treated with antibiotics, and treatment should also be given to the patient's partner. As with Chlamydia, further testing is recommended once treatment has ended to check whether the infection has cleared. For more information, read the factsheet on gonorrhoea.
Herpes genitalis (genital herpes)
Gential herpes is a highly contagious viral condition caused by the herpes simplex virus (HSV). It principally infects the skin and mucous membranes of the genitals and rectum, but can also appear in areas such as the mouth. It is transmitted primarily through physical and sexual contact. During birth, the presence of herpes simplex virus on the genitalia or in the birth canal is a threat to the infant. Infection in the newborn infant can lead to herpetic meningitis, herpetic viremia (herpes virus particles present in the blood) and chronic skin infection.
The symptoms of herpes simplex virus usually occur a week after infection, but sometimes take longer to appear. Initially, the skin becomes reddened and multiple small blisters filled with a clear, straw-coloured fluid appear. Prior to the presence of blisters, the infected individual may also experience increased skin sensitivity, tingling, burning or pain at the site where blisters will appear. Later, the blisters burst leaving shallow, painful ulcers which eventually scab and heal over a period of 7 to 14 days.
The outbreak may be accompanied by other symptoms such as:
- swelling and tenderness of the lymph nodes in the groin area.
- in women, vaginal discharge and painful urination.
- in men, a possibility of painful urination if the lesion is near the opening of the urethra.
- fever.
In most cases, a description of the condition and the appearance of the blisters will be enough to make a diagnosis.