What is an STI? Sexually transmitted infections are considered a topic of taboo that is rarely discussed publicly compared with other health conditions. Due to the stigma attached to STIs, many of us are ashamed to discuss this topic with other people. This can lead to a lack of information about the topic – or even worse, reluctance to receive proper diagnosis or treatment.
STIs are considered infections that young people are typically affected by. In fact, in recent years, adolescents and young adults aged between 15 and 24 years accounted for over 50 percent of people diagnosed with STIs and STDs. Social factors that generally affect case numbers include communities where sexual health care and education is of lesser quality.
Of several different bacteria, viruses and parasites responsible for sexually transmitted worldwide, around eight of these pathogens are responsible for the greatest number of sexually transmitted infections. In Ireland, the number of people newly infected with sexually transmitted infections has been on the increase, with over 14,000 reported cases of STIs in 2018; of these cases, there were over 2,400 cases of gonorrhoea and almost 490 cases of early infectious syphilis.
As sexually transmitted infections are considered a taboo and less-talked-about health topic these days, let us explain to you the difference between an STI and and STD, the signs of an STI, as well as STI diagnosis and forms of STI treatment. In our article, we discuss various types of sexually transmitted infections to give you an overview of this crucial health topic.
What is an STI?
A sexually transmitted infection (abbreviated to STI) is an infection that is passed from one person to another by sexual contact. Anyone from any age group, social status and gender can be infected with an STI. However, those particularly at risk of contracting STIs are young people, gay and bisexual men, people working in the sex industry, people living in areas where STIs are particularly prevalent and people with limited access to sexual health services.[4, 5]
STI vs STD: what is the difference between STI and STD?
Although the terms are very often used interchangeably, there is a difference between STI and STDs. Sexually transmitted diseases start as infections. Infections are caused by pathogens entering the body and multiplying there. An infection then becomes a disease when the pathogens start to damage the body’s cells. Infections can generally cause symptoms and complications, but this is not always the case – some STIs never lead to any symptoms or cause you real health problems. Diseases, by contrast, cause specific health complications.
It’s important to note that some sexually transmitted infections, such as HPV, rarely develop into sexually transmitted diseases – they tend to clear up by themselves over time.
How do STIs occur?
We’ve briefly discussed social factors that could lead to the occurrence of STIs within a population, but what are the physical causes of a sexually transmitted infection? Sexually transmitted infections are predominantly transmitted through sexual contact involving:
- Body parts such as the urethra, vagina, penis, rectum, mouth, hand
- Bodily fluids such as semen, vaginal secretions, urine
Some STIs can additionally be spread through blood or blood products, and some STIs, including syphilis, hepatitis B, HIV, chlamydia, gonorrhoea, herpes, and HPV can be transmitted from mother to child during pregnancy and childbirth. Being infected with sexually transmitted infections such as HSV type 2 and syphilis can additionally increase your risk of becoming infected with HIV.
Did you know that there have been studies investigating the link between male circumcision and the prevalence of STIs? Although limited conclusive results have been drawn from these studies, male circumcision is still being considered as playing a role in preventing HIV in some parts of the world.
What kinds of STIs are there?
There are several different types of sexually transmitted infections. They vary in many ways, including how common they are in certain areas of the world, which infections trigger noticeable symptoms, how they are treated, and also – in some cases – how they are transmitted. Here’s a list of common STIs – along with how they are more commonly referred to:
Chlamydia trachomatis, more commonly known as chlamydia, is one of the most common sexually transmitted infections worldwide, accounting for 92 million cases worldwide back in 1999, according to the World Health Organization (WHO).
Neisseria gonorrhoeae – also known as gonorrhoea – affects more than 78 million people worldwide. Pregnant women can transmit this infection to their child during pregnancy and childbirth.
Treponema pallidum is the pathogen known for causing syphilis. Early infectious syphilis cases reportedly increased between 2017 and 2018. This disease can have very serious consequences if left untreated.
Mycoplasma genitalium is considered an uncommon sexually transmitted disease. The risk of transmission is said to be lower than that for chlamydia.
Mycoplasma hominis affects around 21 to 53 per cent of all sexually active men and women.
Trichomonas vaginalis is the most common sexually transmitted infection that can be cured. The infection is more common in women than in men. About one in five people with a previous infection will become infected again.
Ureaplasma uralyticum can be detected in 30 to 40 per cent of all sexually active men and 40 to 80 per cent of all sexually active women. An infected woman can contract ureaplasma during pregnancy and transmit ureaplasma to her child.
Ureaplasma parvum affects more than 89 per cent of all women, most of whom have no symptoms.
Gardnerella vaginalis actually occurs in the human intestine. However, it can be transmitted from the anus to the vagina. Women are affected by this infection very often. Infection is mainly associated with inflammation of the urethra; discomfort during urination can occur.
Herpes Simplex Virus, also referred to as HSV-1 or HSV-2, enters the body in several ways. With HSV-1, the virus enters the body through open wounds in the lip area or through skin wounds, and with HSV-2 (which more often affects women), the virus enters the body through the mucous membrane in the vagina. In rare cases, the viruses also enter through the mucous in the mouth.
Candida albicans affects up to 70 per cent of the population. In healthy people, a candida overgrowth is usually benign. Candida albicans is present in 85 to 90 per cent of fungal infections. In addition to sexual intercourse, the risk of infection can be increased by taking antibiotics or the contraceptive pill. Various factors can lead to excessive growth of Candida albicans, including high cortisol levels and the body’s own gut microbiome.
What are the signs of an STI?
How do you know if you have an STI? How quickly signs of an STI emerge after infection depends on the type of sexually transmitted infection. Sometimes, whether or not you will experience symptoms typical of a certain STI depends on your gender. In other cases, you may experience no signs of an STI at all or you may experience symptoms that are very generic symptoms, such as headaches.
Here we have broken down all STI symptoms experienced by both men and women to give you a better oversight of the various different symptoms you might encounter if you are infected with the following common STIs.
Sexually transmitted infection
Signs of an STI for men
Signs of an STI for women
Pain when urinating, discharge from the urethra, pain in the testicles, formation of skin ulcers
Inflammation of the cervix, pain during urination, scarring/disruption to the fallopian tube, (in the worst case) premature termination of pregnancy
Often no symptoms but if symptoms occur: pain during urination, pus-like discharge, pain/ swelling of the testicles
Vaginal discharge, vaginal bleeding between periods/after sexual intercourse, abdominal/pelvic pain, itchy rectum, purulent discharge from rectum/eyes, sore throat, swollen lymph nodes, swollen joints
Ulcers, especially in the genital area, swelling of the lymph nodes, headaches, rashes on the palms of the hands and soles of the feet, organ disorders, nervous system disorders
Inflammation of the urethra, discharge, pain during ejaculation, pain during urination, inflammation of the rectum, inflammation of the foreskin and penis
Inflammation of the urethra, discharge, bleeding between periods, cervicitis, abdominal pain
Often no symptoms but if symptoms occur: urogenital infections, pain/discomfort in the respiratory tract
Often no symptoms but if symptoms occur: urogenital infections, pain/ discomfort in the respiratory tract, chronic inflammation of the fallopian tubes and ovaries, pelvic inflammatory disease, infertility
Often no symptoms but if symptoms occur: vaginal inflammation, purulent and foul-smelling discharge, burning/ itching of the vagina
Often no symptoms but if symptoms occur: abdominal pain, redness and inflammation in the genital area, frequent urination, discharge, pain when urinating/slight burning in the urethra
Inflammation of the urethra
Inflammation of the urethra and cervix
Symptoms in the mouth and facial area (cold sores), blisters in the genital area, pain when urinating, swollen lymph nodes, fever, localised pain
Pain when urinating, swollen lymph nodes, fever, localised pain, vesicles mainly in the genital area
Discomfort during urination
Often no symptoms but if symptoms occur: gastrointestinal and urogenital tracts affected
Signs of an STI: is pain during sex normal?
Pain during sex, also called dyspareunia, can be one of the signs of an STI; however, this symptom could also be caused by other health factors. This condition affects both men and women, with various causes including:
- vaginismus, which affects the vaginal muscles
- lack of arousal
- vaginal dryness caused by menopause
- a health condition, like constipation, irritable bowel syndrome or endometriosis
- foreskin issues
- inflammation of the prostate gland (prostatitis)
If you experience pain during sex, you can receive an initial indication of an STI with an at-home sexual health test – or you can alternatively visit your doctor to discuss possible causes for this pain.
STI prevention: how to prevent an STI
How effective are condoms at preventing STI transmission?
Condoms work by preventing direct contact between mucous membranes and fluids during sexual intercourse.
The use of condoms or femidoms – when used correctly – during sex reduces the risk of contracting a sexually transmitted infection. If used incorrectly, they can slip off during sex, which decreases their efficacy. It is, on this note, important to recognise that condoms, even if used correctly, do not provide absolute reliable protection. They do, however, still provide a high level of protection from sexually transmitted infections, and they also function well as a method of contraception.
Sexually transmitted infections that condoms can protect against include syphilis, hepatitis C, gonorrhoea, chlamydia, genital herpes and HIV.
Can cleaning sex toys help with STI prevention?
Various sexually transmitted infections can be passed on to a sexual partner without the right hygiene measures. Where condoms may be the most obvious tool for STI prevention, clean sex toys can also contribute to preventing STIs. Sex toys can, in fact, pass on sexually transmitted infections such as chlamydia, syphilis, herpes, bacterial vaginosis and shigella.
Here are some tips on STI prevention through the right sex toy hygiene:
- keep sex toys clean – wash them after each use
- cover penetrative sex toys, such as vibrators, with a new condom each time they’re used
- avoid sharing sex toys
- have a different set of sex toys for each partner
- avoid using penetrative sex toys if you have any open wounds around your vagina, anus or penis
When cleaning your sex toy, make sure you follow cleaning and storage instructions recommended by the manufacturer of your sex toy. Moreover, checking sex toys for scratches in the surface is important, as these lesions could host various germs.
Did you know that many sex toys are made of latex? If you’re allergic to latex, do not use sex toys that are made of, or contain, latex.
Getting tested: how do you know if you have an STI?
While better-quality STI tests are widespread in high-income countries, this is unfortunately not the case for developing countries. That is because testing is often expensive and can involve long waiting times. The only STI tests that are currently less expensive are the HIV and syphilis tests; there are in fact also rapid tests that have been developed to screen these specific two STIs, for which results can be available within 20 minutes. Rapid tests for other STIs are currently in development.
Diagnostic tests are considered indispensable – especially, for diagnosing STIs that are typically characterised as asymptomatic. Many STI tests screen for a variety of sexually transmitted infections; some check specifically for one type of STI.
Can you test for an STI at home?
The topic of sexually transmitted infections is, as we have already mentioned, often considered taboo in society. It is believed that many people do not dare visit a doctor for possible STI symptoms out of shame. A home health test kit offers a discreet opportunity to be examined for various sexually transmitted infections.
STI test kits often require collecting blood or urine samples – a syphilis test, or hepatitis C test, for example, screens for the presence of the relevant sexually transmitted infection in your blood. STIs such as gonorrhoea are often detected through urine tests.
Although collecting a blood sample sounds relatively painful, all that is required for blood tests of this type is a small finger-prick’s worth of blood. You generally then need to collect small drops of blood on either a dried blood spot card or in a sample tube. The process is relatively painless, simple and easy. All that remains after taking the blood sample is sending it to the relevant laboratory, where they will screen your sample for an infection associated with an STD or for antibodies against a certain STI. Results are usually available within a few days following the sample’s arrival in the laboratory.
When should you get tested for STIs?
According to the US Centers for Disease Control and Prevention, it is recommended that all sexually active women should be tested for gonorrhoea and chlamydia once a year – and that all adults and adolescents between the ages of 13 and 64 should be tested at least once in their lifetime for HIV. Advice for pregnant women is that they are tested for syphilis, HIV and hepatitis B during the early stages of their pregnancy. It is also believed that performing an STI test should be regular practice before and after you have sex with a new partner.
Furthermore, sexually active gay and bisexual men should be tested at least once per year for syphilis, chlamydia and gonorrhoea – and potentially more than once a year for HIV. If you have unprotected sex or share injection equipment with others, you should get tested for HIV at least once a year.
STI treatment: how can you treat an STI?
Many people suffer from an unknown sexually transmitted infection. The longer an infection goes unnoticed, the greater the number of people who can become infected. The consequences of a long-lasting, untreated infection can be very serious, such as loss of fertility. The late stages of syphilis result in severely poor health: with nervous system disorders and organ failure – and can eventually lead to death.
Of the various STIs, four are currently curable: syphilis, gonorrhoea, chlamydia and trichomoniasis. The other four are viral infections, which are incurable: hepatitis B, herpes simplex virus (HSV or herpes), HIV and human papillomavirus (HPV). Symptoms or disease due to the incurable viral infections can be alleviated, but the infection cannot be fully cured.
STIs are generally treated with a range of antibiotics given to you by a doctor: chlamydia and other STIs are treated with azymthromacine, doxycycline or ofloxacine, among other antibiotics. Syphilis is often treated with penicillin. Herpes can be treated, but not cured. People affected by herpes can expect antiviral medications to alleviate symptoms instead. Please note that some antibiotics are not recommended for pregnant women; alternative treatment must be discussed with your doctor.
What are the signs of an STI – at a glance
What is the difference between STI and STD?
Although the terms are very often used to mean the same thing, there is a difference between STI and STDs. Sexually transmitted diseases start as infections, whereby pathogens enter the body. An infection then becomes a disease when the pathogens start to damage the body’s cells.
How do STIs occur?
Sexually transmitted infections are mainly transmitted through sexual contact involving body parts, such as the urethra, vagina, penis, rectum, mouth and hand or bodily fluids, such as semen, vaginal secretions and urine. Some STIs can additionally be spread through blood or blood products or from mother to child through pregnancy.
What are the signs of an STI?
How do you know if you have an STI? Symptoms and signs of an STI depend on which STI you are affected by. Sometimes, whether or not you will experience symptoms typical of a certain STI depends on your gender. In other cases, you may experience no signs of an STI at all or you may experience symptoms that are very generic symptoms, such as headaches.
How can I prevent an STI?
The use of condoms or femidoms – when used correctly – during sex reduces the risk of contracting a sexually transmitted infection. Other methods of STI prevention include thoroughly cleaning sex toys or products, such as needles, if you share them with other people.
What are the forms of STI treatment available?
The first step of treating an STI is to visit your doctor for advice. They will likely prescribe you with a form of antibiotics for most STIs. If you have an STI that can’t be cured, you will receive medication to alleviate the symptoms of the STI.
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