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    How are STIs transmitted?

    Understanding STIs

    Everyone knows the dangers of sexually transmitted infections, also known as STIs. From your very first sex education lesson at school you will have been told about the importance of safe sex, not only to prevent unwanted pregnancy but also to prevent the spread of infections and diseases. However, you are never really taught why an STI might spread from one person to another, you are simply told that they will. 

    It is important that you understand the processes in the body that occur when an STI is transmitted as this knowledge can help you to avoid them better in the future. In this article, we will tell you exactly how STIs are transmitted, as well as other questions you may have regarding STIs.

    What is an STI?

    Sexually transmitted infections, also known as sexually transmitted diseases (STDs) are infections that are passed along from person to person, most usually by sexual intercourse or activity. This is not always the case as they can be passed in other ways, for example to a baby from its mother during childbirth. There are many different types of STIs, all of which are caused by different reasons, and all of which are treated in different ways. 

    What different types of STIs are there?

    Below is a table of the most common STIs that can be transmitted, their symptoms, and how they can be treated.




    • Pain when urinating
    • Unusual discharge
    • Pain during sex

    • Unusual discharge
    • Pain when urinating
    • Discomfort in private parts
    Genital WartsItching or bleeding from private parts

    Painless lumps on penis, anus or vagina



    Catephen Ointment
    Genital HerpesBlistering on private parts
    Burning or itching genitals
    Pain when urinating

    Pubic Lice Small insects in pubic hair
    Itching, mostly at night
    White/yellow dots in pubic hair (eggs)
    Medicated shampoos

    Medicated creams
    SyphilisSores on private parts
    Rashes on hands and other body parts
    White patches in the mouth
    HIV and AIDSRaised temperature
    Sore throat
    Body rashes
    Emtricitabine/Tenofovir (Preventative)

    Antiretroviral medicines


    How are STIs transmitted?

    Different types of sexually transmitted infections will be passed on in different ways. However, the most common way that STIs are transmitted is through unprotected sexual intercourse or activity between people, one of which who is already infected, whether they know it or not. If someone knows that they are infected with an STI then they should not partake in any sexual activity until they have received treatment, or unless they are able to have protected sex without the risk of transferring the infection. If someone gets an STI then they will need to let any recent sexual partners know so they can get themselves tested too. For some infections you may need to tell all previous partners, your doctor should be able to advise on this.

    Can STIs be transmitted through condoms?

    The main piece of advice given for having safe sex is to use a condom. Condoms, when used correctly, can provide excellent protection against the transmission of sexually transmitted infections. However, it is important to note that condoms are not a guarantee that STIs will not be transmitted. This is similar to how someone can still become pregnant even though they are using a condom. 

    Can you transmit an STI through kissing?

    You may be concerned about transmitting an STI from kissing alone. Thankfully, you cannot pass the majority of sexually transmitted infections via kissing, however, there are some that can be transferred through kissing. The most common STIs that can be given by kissing are herpes when the infection is in or on the mouth, or cytomegalovirus. 

    Can STIs be transmitted through the toilet?

    Public toilets can be an experience, to say the least, and the last thing you want to be worrying about is whether or not you’re going to contract an STI from a previous occupier of the same cubicle as you. The chances of getting an STI from a toilet seat are low. Bacterial infections, such as chlamydia or syphilis, cannot live on surfaces and cannot be caught from a toilet seat. Some viral infections however can live outside of the body, and in theory, can live on a toilet seat. However, it is highly unlikely that you will ever get an STI from a toilet seat. 

    Can you transmit STIs without ejaculating?

    Almost all sexually transmitted infections are passed on by the physical act of sex, and not through ejaculation. Some infections can live in a man’s ejaculate, however, the act of ejaculation does not transmit the disease. 

    Can STIs be transmitted through breastfeeding?

    When you are trying to breastfeed your child you may be concerned about passing on an STI, especially if you know that you have one. You can still breastfeed your child if you have certain STIs, however, there are certain STIs that can affect breastfeeding. You should not breastfeed if you have HIV or AIDS, You may also need to take an antibiotic called metronidazole in order to breastfeed if you have trichomoniasis. If you have herpes, you should be okay to breastfeed as long as there is not a sore in the area. 

    Can STIs be transmitted through oral sex?

    Oral sex is actually one of the most common ways that sexually transmitted infections transfer from person to person. The most commonly transferred STIs through oral sex include gonorrhoea, genital herpes, syphilis, and human papillomavirus. Whilst they are less common, you can also pass on other infections, including chlamydia, HIV, genital warts, pubic lice, and hepatitis A, B, and C. 

    Frequently Asked Questions

    What are the most commonly transmitted STIs in England?

    Whilst there are many different sexually transmitted infections, there are some that are much more common than others. The most commonly transmitted STIs in England include:

    How can I prevent STIs?

    There are some ways that you can prevent STIs, but perhaps the best way to do this is by using a condom as this provides a barrier between skin. This will greatly reduce the risk of infection. Other things that you can do in order to prevent STIs include keeping track of your sexual partners, you are at a higher risk of infection the more partners you have. You should also be extra safe when you are doing sexual activites that pose a higher risk, such as anal sex. 

    How can I treat STIs?

    Each sexually transmitted infection will be treated differently. Some STIs will have specialised treatments such as chlamydiaherpes and genital warts. Other STIs will be treated with antibiotics, such as syphilis and gonorrhoea.  

    Getting Your Medication

    Do I need a prescription for STI medication?

    When you have been diagnosed with an STI your doctor will then tell you what medication they think is best to treat your condition. In order to get this medication, they will provide you with a prescription. You can only purchase STI medication when you have a valid prescription from a doctor or an independent prescriber. 

    Can I buy STI treatments online?

    You can purchase the sexually transmitted infection medication that you require online from UK Meds. You can either use an existing prescription in order to place your order, or you can complete consultation with an independent prescriber. If you have a successful consultation you will then be given a prescription and you will be able to purchase the medication you need.


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