Sex, STI’s and safer sex

If you are having sex or any type of sexual contact with another person, you are at risk of transmitting an STI. Some of those risks can result in a lifelong infection, serious health problems, and some of them can kill you if untreated. If that sounds like scaremongering: good. This is serious stuff, because every time you throw  your genitals on the sex table without knowing what risks you are taking, you are essentially risking your life, and that of your current or future partners if you don’t act responsibly.

Even in the best circumstances, with all precautions taken, it is still possible to catch an STI. Part of this is limits on current testing, or a lack of complete treatment for infections.  All you can do is be informed of the risks, talk about the risks with your partner(s) and do everything you can to mitigate those risks; whether it is using barrier methods, limiting your sexual partners or regular re-testing at your local GUM clinic.

Sexual health education in this society is still pretty poor, there is still a stigma to getting tested and being infected with an STI, and people don’t talk enough about sexual health, past history and safer sex precautions before they take their underwear off. The aim of this post is to give some scientific facts about the main STIs, transmission, and finally some implications for non monogamous folk in particular.

Some facts on the major sexually transmitted infections:


  • HIV is virus which reduces the body’s ability to fight infections. If left untreated it progresses to acquired immunodeficiency syndrome (AIDS) where the body is susceptible to infections and viral induced cancers which can be fatal.
  • There is no cure, but HIV treatment  such as anti-retrovirals can give those with HIV healthy, active lives.
  • HIV is transmitted via infected blood, semen, vaginal fluids or breast milk, through unprotected sexual contact with someone infected with HIV, sharing infected needles or other blood contact equipment and from HIV+ mother to child (when infection prevention measures are not used).
  • Transmission rates vary by sexual act and by orientation and known HIV status:
  • Transmission via fellatio is much lower than vaginal or anal sex (approx 0.04% per exposure versus 0.08% and 82% respectively, assuming partner is HIV+) 15
  • Data on transmission rates for cunnilingus is patchy at best, and female to female sex carries an extremely low risk of HIV transmission. There are only five known cases of F-F HIV transmission in medical history, and in all cases there were other risk factors (injecting drug use, male partners). However it is thought the main risk comes from fingering, sharing insertable toys and fisting rather than oral sex on females 16
  • Prevention: use condom for vaginal or anal sex, consider using condoms or dental dams for oral sex, don’t share needles or other blood letting equipment such as scalpels, skin staples etc 14


  • Genital chlamydia is the highest bacterial sexual infection in the UK
  • People can be infected but asymptomatically, but left untreated can lead to more serious fertility conditions in both sexes
  • Genital chlamydia can be caught through unprotected vaginal, anal or oral sex or genital contact with an infected partner
  • It is easily transmitted via vaginal or anal sex, but less common in oral sex 17
  • Chlamydia is easily treatable with antibiotics, especially if caught early
  • Prevention: use condoms with new or casual partners, and get tested regularly


  • Syphilis is a bacterial infection that causes sores on initial infection, but if left untreated can cause miscarriage, foetal abnormality or heart, respiratory tract or central nervous system problems which can be fatal
  • Syphilis is transmitted through unprotected vaginal, oral or anal sex or genital contact with an infected person
  • Treated with antibiotics, especially if caught early, but in later stages damage is irreversible
  • One of the less common STIs but on the rise in recent years.
  • Prevention: condoms and barrier methods for sexual contact will reduce the risk of transmission drastically, but sores are infectious and may not be covered with the barrier

Genital Warts

  • Genital warts are the most common viral sexually transmitted infection in the UK, caused by the human papillomavirus (HPV), of which there are over 150 types 21
  • Two HPV types in particular (16 and 18) are responsible for the majority of HPV caused cancers, particularly cervical, anal, vaginal, vulval and penile cancers, as well as being strongly associated with oropharyngeal cancer 21
  • Transmitted through unprotected sexual vaginal, oral or anal intercourse or genital contacted with an infected person.
  • A person can be infectious but asymptomatic, and if exposed there is approximately a  2/3 chance of transmission
  • Genital warts cannot be cured, the infection is for life, although not infectious all the time 10
  • Warts normally disappear without treatment over time, but can be burned/frozen off
  • Prevention: Condoms or barriers can give some protection against warts, but not complete protection as may come into contact with infected skin. Additionally the NHS offer a HPV vaccine to teenage girls to protect against HPV caused cervical cancer and women over 25 are tested as part of their cervical smear tests 22


  • Gonorrhoea is the second most common bacterial STI in the United Kingdom
  • Transmitted via vaginal, oral or anal sex or genital contact with an infected person
  • Infection can be asymptomatic
  • If left untreated can cause serious fertility issues for women
  • Treated with antibiotics, but some strains are becoming resistant and multi antibiotic therapy is required
  • Prevention: condoms and barrier methods for all methods of sexual contact

Hepatitis B

  • Hepatitis B is a bloodborne viral infection that can be prevented through vaccination
  • Transmitted by coming into contact with sharps, blood products or sexual contact with infected persons
  • The hepatitis B virus (HBV) causes hepatitis (inflammation of the liver) and can also cause long term liver damage
  • Symptoms can be flu-like, others are asymptomatic
  • Treated with antivirals (but not universally appropriate or successful). If still infected after six months, considered a chronic HBV infection, currently 0.3% of the UK population 12
  • Prevention: not sharing needles for drug use, using condoms for sex, having piercings or tattoos at reputable licenced premises


  • Genital herpes is the most common orally transmitted STI in the UK 17 and is caused by the herpes simplex virus (HSV). There are two types of herpes virus, HSV-1 and HSV-2 and both types can cause genital herpes
  • Initial infection usually results in sores or blisters, which are extremely infectious
  • The virus can lay dormant and periodically reoccur. These recurrences of the virus can be asymptomatic yet be infectious
  • Transmitted via direct contact with the virus such as vaginal or anal sex, as well as genital contact or oral sex with someone with cold sores.  The skin around the genitals, anus or mouth may be infected, and shed viral particles asymptomatically 18
  • Diagnosed by testing a sore or blister, blood antibody tests are not routine in the UK, so it is difficult to determine if someone carries the virus unless they are symptomatic
  • There is no cure for genital herpes. Treatment with antiviral drugs may reduce the symptoms and length of infection, but the virus remains in the respective ganglion for life 10
  • Prevention: using condoms or barrier methods for genital contact reduces the risk of transmission, but does not eradicate it
  • Abstaining from sex or sexual contact with anyone who has an active herpes lesion on mouth or genitals, as this is the most infectious period

UK Transmission Data

So now we know the basics on the actual infections, let’s have a look at transmission of STIs in the UK. This data is taken from the Health Protection Agency and is their data from 2011, the latest complete set of data publicly available.

In 2011 the number of new sexually transmitted infections diagnosed by the NHS increased by 2% on the previous year’s total (419,773 to 426,867). The greatest increases of STI transmissions in 2011 were gonorrhoea (25%; 16,835 to 20,965), infectious syphilis (10%; 2,650 to 2,915), genital herpes (5%; 29,794 to 31,154),  and genital warts (1%; 75,415 to 76,071). In 2011 cases of genital chlamydia fell by 2% (189,314 to 186,196)

The highest rates of new STI diagnoses in 2011 were among heterosexuals under 25 years old. Out of overall infections by type, 66% (58,077/88,429) with chlamydia, 56% (38,657/69,311) with genital warts, 57% (6,678/11,778) with gonorrhoea, and 43% (12,469/28,687) with genital herpes were aged 15-24 years 10.

In 2011 there were 73,659 people in the UK living with a diagnosed HIV infection and receiving care 13. It is suggested that there are 22,600 people living in the UK in 2011 who were HIV+ but unaware of their status 19. New HIV infection rates in homosexual men and heterosexuals are roughly the same per year, and the majority of HIV diagnoses in the UK are in men 2.

The majority of new HIV diagnoses in 2011 were in those aged between 30 and 34  (1,089), closely followed by the 35-39 age group (1,073) and the 25-29 age group (979). Since records began, the largest proportion of HIV diagnoses have been among people in their thirties. In the period 2000-2010, new HIV diagnoses in the over 50 age group has nearly tripled 2 and recent HPA shows a marked increase in STI transmission in the over 50 age range 20.

It is important to note that the datasets have restrictions and flaws on several counts. Important factors such as national and local NHS initiatives for targeted sexual health screening increased the amount of people seeking tests, and increases recorded transmission rates. Additionally male sexuality is recorded in HPA data, but not female, emphasising the male-male sexual health risk stereotype. Finally, relationship type is not captured, so we are unsure if the majority of people are single, monogamous, polyamorous, non, monogamous or other, all of which may impact directly on safer sex approach and infection rates.

Safer sex implications for non monogamy and polyamory

In some respects, approach to safer sex should be the same across the board – whether you have one partner at a time or ten, you are exposing yourself to another person ( and indirectly all their previous sexual partners), and you need to have a clear, honest discussion about your sexual health history, safer sex practices, and testing arrangements. I consider it prudent to have full STI screening at regular intervals, and particularly before embarking on a new sexual relationship. Whether you decide to use barriers or fluid bond once you are tested clear, is up to you.

For anyone in any other type of non mongamous relationship, whether it be someone single who enjoys lots of casual sex with lots of different people, swingers, open, polyamorous folks or closed non monogomy, there are extra things to consider. Because you aren’t exposing yourself to just one person (and their past partners), but several, the extrapolated numbers and potential risks quickly become quite scary. Even if you use barriers for penetrative sex, there is still the risk from oral sex where you are most likely to catch herpes, gonorrhoea or syphillis 17. If you use condoms or dental dams for oral, there is still a risk of catching an infection from an area not covered by a condom or dental dam, and unfortunately two of the three infections caught this way are incurable (herpes and warts)3.

There really are no hard and fast rules here – it really is for each person in a relationship to decide for themselves what (if any) risks they are prepared to take, and to set their own boundaries for safer sex rules. Discussion, negotiation and agreements can be made to cover things such as safer sex methods, risk reduction, agreed practice, accepted behaviours and testing schedules, and ideally this needs to be done before any hanky panky takes place.

Having multiple partners means risking cross-infecting, so it is important to be clear on what things need a barrier (such as dildos or vibrators or hands) and which things you need separate items of (such as pinwheels, crotch ropes, leather items).  Additionally there can be agreements on what happens if a barrier fails, someone is exposed to a risk, or tests positive to an infection. Making plans for the worst case scenario doesn’t make everything better, but planning for it can raise awareness of the risks, and if the worst does happen, can take the panic out of the situation.

The single most important thing about sexual health is to be knowledgeable, know about the infections, know the risks of sexual behaviour and be clear about what steps you take to reduce your risks of transmission, and what you seek in your partners. Whilst you can’t dictate to another how they should behave in relation to their sexual health, you can expect them to be honest, and if their behaviour isn’t acceptable to your level of risk, to not engage in sexual activity with them. Every time you have sex, with every person you have sex with can potentially result in a life sentence if things go badly. Remember folks, herpes is for life, not just for Christmas.