Last partial update: July 2016 - Please read disclaimer before proceeding

 

Avoiding Sexually Transmitted Diseases

Most sexually transmitted diseases (STD) can be prevented by common sense and a responsible attitude to sex. This unfortunately is not always the done thing and unsafe sexual practices are responsible for about one per cent of all burden of disease. The list of serious sexually transmitted diseases is large and includes HIV/AIDS, hepatitis B, genital herpes, chlamydia, syphilis, genital warts and gonorrhoea. Cervical cancer from Human Papilloma Virus could also be added to this list and the trauma associated with an unwanted pregnancy should not be forgotten.

 

STDs are most common in young people. (The average age of infection with chlamydia in Australia is 15 to 24 years in women and 20 to 35 years in men.) Young people are more vulnerable because they are less likely to be in a long-term relationship, are more likely to have multiple partners, and are more likely to take risks such as participating in intercourse without condoms.

 

Preventative measures were partly covered in the section on the preventing teenage pregnancy and this section is worth reading again. Prevention should include the following.

 

 

Diseases that are predominantly transmitted by sexual intercourse 

 

Chlamydia – A sexually transmitted disease epidemic in Australia

Chlamydia is a sexually transmitted infection that is increasing greatly in incidence in both young men and young women; the incidence in Australia has increased significantly over the past 12 years. (74,300 cases were reported in Australia in 2010.) It is difficult to diagnose because in both men and women there are often very few symptoms, if any. At least 50 per cent of infections are symptom free. Women with the infection sometimes experience a vaginal discharge, pain with sexual intercourse or abdominal pain, but most symptoms are mild and transient and thus not acted upon. The highest rates of infection occur in 15 to 25 year old females, the group most at risk of contracting the disease, and 25 to 35 year old males. However, the disease is present in all adult age groups.

 

Long-standing chlamydia infection in women is important because it can cause infections around the ovaries and fallopian tubes. The resultant scarring may lead to fertility problems, with about five per cent of women with the disease becoming infertile. It can also result in ectopic pregnancies. (Ectopic pregnancies are pregnancies that occur in the fallopian tubes and they can cause serious problems due to bleeding.)

 

The main risk factor for chlamydia is having multiple sexual partners.

 

To assist in preventing transmission of this disease, it is important that condoms are used with all sexual intercourse. When entering a long-term relationship, it is important that both partners are tested for chlamydia and other sexually transmitted diseases before condom use is ceased. (In the past, it has mostly been women that have been tested for the disease.)

 

Chlamydia screening programs have been introduced in several countries and have helped to significantly reduce the incidence of the disease. Those at high risk (i.e. people who do not use condoms all the time, especially if they have multiple sexual partners) should discuss being screened for the disease on a yearly basis with their GP. Pap smear visits are a good time to also do clamydia screening tests, although Pap smears are usually done every two years. At present few at risk females are screened in Australia. Some GPs are wary about talking to young people about their sexual activity, fearing that it might stop them from coming back. Thus, do not be afraid to bring up the topic even if a doctor doesn’t.

 

Chlamydia infection is diagnosed by testing a urine sample and is easily treated (with antibiotics); but re-infection will obviously occur unless condom use is maintained and all present sexual partners are treated. Past partners should also be notified and future long-term partners will need to be screened for the disease.

 

Genital herpes

There are two herpes simplex viruses that cause genital herpes; type 2 (HSV-2) and type 1 (HSV-1). HSV-1 is the usual cause of cold sores around the mouth but it can also cause genital herpes if oral lesions are present when oral sex is practiced. The HSV-2 virus is the more common cause of genital herpes, although in the under 20 age group HSV-1 has become the more common virus involved, presumably because of a higher incidence of oral sex.

 

Genital herpes is most commonly acquired in late adolescence and early adulthood and the risk increases with the number of sexual partners. In all, about 90 per cent of adult couples will have at least one partner who previously contracted oral HSV-1 from exposure to an oral cold sore, most commonly in childhood. Thus, most couples will be exposed in some way to this virus. People who have previously been had oral HSV-1 cold sores are immune from getting HSV-1 genital infections and tend to get less severe initial HSV-2 infections which are often asymptomatic. Thus, many HSV-2 infections go unnoticed.

 

Constant condom use is not 100 per cent effective in preventing transmission of genital herpes but is helpful in preventing transmission from an infected male to a female partner. Condom use is less effective in preventing female to male transmission, mainly because the usual site of infection in females is the vulva. However, while condom use can slow down the process, the reality is that in a long-term relationship an infected partner will almost always infect an uninfected partner eventually. (The rate is about 10 per cent per year.) 

 

A person with their first infection usually has an irritated looking red rash that may be blistery and ulcerated. It is often painful and can last up to three weeks. However, milder presentations are becoming increasingly common with some mild enough for the condition not to be noticed. The severity of the infection is more to do with the immune response of the infected person and not the virus itself. Thus, there is no guarantee that a person infected from a partner with mild symptoms will also develop an infection with mild symptoms. Very severe reactions including spread to other parts of the body including the brain can occur in people who have a compromised immune system e.g. people with HIV.

 

Both herpes simplex viruses unfortunately continue to live in the skin nerve endings near the site of the initial infection and recurrences of the infection occur at regular intervals. These recurrences are milder than the initial infection, often lasting less than a week and tend to become less frequent with time.

 

Most people who test positive to HSV-2 have no idea that they have the disease. It is likely that most transmissions occur from people with a mild, asymptomatic infection (i.e. little or no evidence of infection) and people who have had obvious evidence of the disease are still likely to be infective at times when they have no symptoms; that is, in between recurrences. (It is still wise however not to have intercourse while active infection is present.)

Testing for the disease is best done by taking a PCR swab from an active lesion. Blood testing is not as helpful as it does not tell where the infection lies. (It will be positive in people with an oral cold sore as well.)

 

Blood testing can however be useful in testing a woman who wishes to become pregnant and has a male partner with the disease. Women who become infected while they are pregnant have an increased risk of transmitting the illness to the foetus, especially if the infection occurs in the third trimester. If the woman is not infected, treatment of the male partner throughout the pregnancy with suppressive anti-viral drug therapy and abstinence from vaginal sex later in the pregnancy is recommended. Transmission to the baby during delivery from a mother with an active infection may also occur and caesarean section is recommended when active infection exists at the time of delivery.

 

Treatment is with the antiviral drugs acyclovir and valaciclovir. These medications reduce the severity of initial infections but treatment of the initial infection does not influence the incidence of recurrent infections. However, long-term suppressive drug therapy does reduce recurrence rates by about 70 per cent and will obviously also help reduce the likelihood of transmission; but not eliminate it!! (This is particularly useful early in relationships and in pregnancy as described above.) The use of antiviral drugs during recurrences reduces the length of infections by up to 24 hours.

 

Unfortunately there is no vaccine against this disease.

 

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HIV/AIDS

HIV is a viral infection that is mainly transmitted through sexual intercourse, with anal intercourse being the easiest method of spread. In Australia it mainly occurs in homosexual men (89 per cent), with the average age at diagnosis now being about 34 years in this group. Heterosexual transmission is responsible for about 10 per cent of new cases.

 

In Africa and other developing countries, vaginal intercourse is the more common method of spread. Transmission associated with intravenous drug use accounts for only about two per cent of cases in Australia but is a more common method of spread in Europe, Asia and the USA. Worldwide there were five million new cases in 2003.

 

Transmission by accidental needle stick injury only occurs in about 0.3 per cent of exposures to needles used by infected individuals and transmission by blood transfusion is exceedingly rare.

 

Perinatal transmission from an infected mother to her baby occurs in about 20 to 45 per cent of cases unless preventative measures are taken. Such preventative measures can reduce this rate to about 5 per cent and include antiviral drug treatment during the pregnancy, the labour and after delivery, birth by caesarean section, and avoidance of breast feeding.

 

Generally the rate of HIV infection is starting to increase again and between 2000 and 20005 there was a 41 per cent increase in new case diagnosed. (In

Victoria, the number of new HIV cases increased from 140 in 1999 to 286 in 2005.) This increase has coincided with a significant rise in the incidence of unprotected anal intercourse amongst homosexual men. The reason for this is not clear, although it may be that men are less afraid of HIV/AIDS now that there is better treatment available.

 

Preventing HIV/AIDS infection involves the following.

 

Post HIV exposure prophylaxis

People who have had unprotected sexual intercourse with a person who has HIV or has a high risk of having HIV can reduce their risk of contracting the disease by taking a course of antiretroviral medications. Two or more drugs are usually taken for a period of 28 days and should be commenced as soon as possible after contact (within 72 hours).

 

Similar post-exposure prophylaxis can be used for needle stick injuries where the chance of HIV exposure is significant. This treatment can give no guarantee of infection avoidance and should never be seen as a back up for using unsafe sexual / drug use practices.

 

Preventing needle stick injuries

Needle stick injuries can be minimised by adequate training of health professionals in the safe use and disposal of needles. Important points include the following.

  • Needles should not be re-capped or bent after use
  • Needles should not be removed from disposable syringes after use
  •  ‘Sharps’ containers need to be rigid
  • ‘Sharps’ containers should be close to work sites to aid immediate disposal
 ‘Sharps’ containers need to be kept out of the reach of children.

 

Hepatitis B

Hepatitis B is a viral infection that affects the liver, with some chronic infections causing serious liver damage and liver cancer. About 25 to 40 per cent of people with chronic infections die from the disease. Whether infected individuals eradicate the illness or develop a long term chronic infection depends on the age at which they are infected. People who develop the disease in early childhood have 90 per cent chance of being chronically infected. Only about five per cent of those infected in adult develop chronic disease.

 

Most cases in countries with a high incidence of the disease, such as China, South East Asia and the Pacific nations, occur due to infection from mother to baby at birth. In adults, transmission is mostly through sexual contact or injecting drug use. There are thought to be about 200,000 carriers of the disease in Australia. Transmission by needle stick injury occurs in about three to 30 per cent of exposures from needles used by infected individuals, depending on the infectiousness of the affected person.

 

Preventing Hepatitis B infection involves the following.

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Cervical cancer

 

About 90 per cent of cervical cancer is caused by the human papilloma virus that is contacted as a sexually transmitted disease. This topic is covered in detail in the section on cervical cancer.

See section on cervical cancer prevention

 

  

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Some safe sex messages for teenagers

  • Decide on your sexual limits: Think ahead about your ‘sexual activity limits’ and how they can be enforced without harming relationships. Abstinence is a very reasonable option for those who wish.
  • Plan strategies to help avoid exceeding sexual limits.Teenager girls can:
    • Talk about feelings / limits with their boyfriend / girlfriend and emphasise that self-respect is an important issue for them.
    • Plan ways of avoiding getting into difficult situations. Parents can be a help here.
    • Have prepared refusal strategies for ‘difficult situations’ should they occur. Most people will respect the right of other to limit their sexual activity. However, this is not always the case and if problems arise, then tactics such as saying that they need to go to the toilet or feel like vomiting, or, for females, that they have their period, can be helpful.
  • Keep a clear mind. The ability to keep to planned sexual activity levels and implement planned refusal strategies requires clear thinking. This can only be achieved in the absence of illicit drugs and significant amounts of alcohol.
  • Be aware of strategies to avoid drink spiking / date rape. (See Teenagers going out section.)
  • Always use condoms without exception. Condoms are vital for protection from sexually transmitted diseases and provide reasonable contraception for people having very occasional sexual intercourse. However, alone they are not really adequate contraception for people who are having sex regularly and some other more reliable form of contraception needs to be used AS WELL.
  • Be aware of emergency contraceptive options should you need them. (See section on unplanned pregnancy in the contraception section.)

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