Most important STIs

Chlamydia and LGV (lymphogranuloma venereum)
Chlamydia is common in the Netherlands. Chlamydia is highly contagious and can cause infection in the vagina, anus, throat and in the urethra of the penis. It is even possible to get chlamydia in your eye, through semen or by rubbing your fingers in your eye. It is good to be aware of the ways you can be infected so you take extra measures to prevent an infection.

LGV is a variant of chlamydia. LGV occurs almost exclusively in men who have sex with men. LGV causes symptoms more often than a regular chlamydia infection.

Complaints due to chlamydia

Persons with vaginal chlamydia usually do not have any symptoms.
If they do, these are some of the symptoms:

  • bleeding during or after sex, or between periods
  • pain when urinating or during sex
  • change in discharge (amount, smell and colour)
  • fever
  • abdominal pain

Those with a penis are more likely to notice symptoms such as:

  • pain, burning or tingling sensation when urinating
  • discharge from the urethra

If you have chlamydia in the anus, you may have these symptoms:

  • itching
  • irritation
  • slimy discharge

Chlamydia in the throat usually does not cause any symptoms.

Complaints for LGV
  • ulcer in your rectum, on your penis or in your throat
  • inflammation of your lymph nodes
  • pain when urinating
  • fever

If left untreated, chlamydia can lead to other problems. A chlamydia infection can spread to the abdominal cavity and fallopian tubes. This can lead to reduced fertility.

With men, when a urethra chlamydia is not treated, the infection may contaminate the epididymis on the testicles and cause inflammation.

You can get chlamydia and LGV multiple times.

Treatment is easy for chlamydia. Our advice is to get tested every 3 months.

Chlamydia is easily treated with a 2-tablet antibiotic or a one-week course of antibiotics. LGV infection is treated with a total of three weeks of antibiotics.

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Gonorrhea is also called ‘the clap’. It is very contagious (it is easily spread). It can infect the vagina, anus, throat and, with men, urethra (urine tube).

Complaints with gonorrhoea

Most people with a vagina have few or no symptoms with gonorrhoea.

Complaints you may have:

  • discharge from the vagina
  • pain during urination or sex
  • loss of blood during or after sex

Complaints with gonorrhoea in the anus:

  • itching and/or irritation
  • slimy discharge
  • feeling of having to defecate

Complaints with gonorrhoea in the penis:

  • green/yellow or watery discharge from the penis. Sometimes it even drips from the penis.
  • pain when urinating

A gonorrhoea in the throat usually does not cause any symptoms.


If you have an STI, it is important to get treatment in time. If left untreated, it can lead to other problems. For example, a gonorrhoea infection can spread to the abdominal cavity and fallopian tubes, which could later lead to reduced fertility. The (epididymis) balls can also become inflamed.
Test yourself preferably once every three months. You can get Gonorrhoea several times.
Schedule an appointment.

Gonorrhoea is easily treated with a course of antibiotics.

Need more information?
Our nurses can answer any of your questions.

Syphilis is a bacterial STI that you get through penetration or oral sex. The risk is highest if no condom is used. But be aware that you can also get syphilis from just kissing. It is common for syphilis to go undetected for some time. There are no symptoms, or the symptoms look like something else harmless (an allergic reaction, for example).

A syphilis infection has three stages. Each stage has different possible symptoms:

1. Stage 1
Syphilis often starts with a painless sore on or around the vagina, penis, anus or in the mouth. While most of the time, the sore/ulcer disappears on its own after 3-6 weeks, you remain highly contagious.

2. Stage 2

  • A rash on your upper body, arms, legs (including palms of hands and soles of feet)
  • Hair loss
  • Sometimes:
    • Poor appetite
    • Fever
    • Swollen lymph noden
    • Headaches
    • Insomnia
    • Eye complaints, loss of sight
    • Ear complaints, hearing loss, tinnitus

These symptoms go away on their own. At this stage, you are still contagious.

3. Stage 3
Syphilis can spread throughout your body via the bloodstream. Up to more than 10 years after infection, organs like the heart and brain can be permanently affected and severe symptoms of illness can occur. Though at this stage, you are no longer contagious.


If you have an STI, it is important to get treatment in time. If left untreated, it can lead to other problems. Untreated syphilis can have serious consequences (see stage 3).

A syphilis infection is often only visible in a test after 3 months. Therefore, test yourself every 3 months to get treatment and to avoid long-term problems. Schedule a test.

If syphilis is detected in time, it can be easily treated with a course of antibiotics. You then only need to be treated once with two syringes of penicillin. You are then no longer contagious.

If syphilis is discovered at a later stage, you need to be treated three times with two syringes of penicillin. If ‘neuro-syphilis’ (syphilis in the brain) is suspected, we will need to refer you to the hospital for further tests.

After treatment for syphilis, we advise you to return several times in the following 2 years for follow up blood tests. You can get syphilis several times.

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Hepatitis A
Hepatitis A is a highly contagious inflammation of the liver caused by a virus. There are two main ways to contract Hepatitis A: through faecal contamination (food, water, or contact with towel or tap) or through anal sex (rimming, fingering or fisting).

There is no cure for hepatitis A. You have to let it run its course. Fortunately, you can easily prevent infection with two vaccinations.


You usually develop symptoms two to six weeks after infection.

Symptoms that occur with hepatitis A:

  • Nausea
  • Pain in the right upper abdomen
  • Flu-like symptoms such as fever, muscle or joint pain and general malaise
  • Fatigue
  • Jaundice: the whites of the eyes and skin are yellow
  • The urine is brown
  • The stool is grey-white

In many cases, hepatitis A is diagnosed by a doctor after a physical check and case history but it will need to be confirmed by a blood test. Unfortunately, we cannot do this test at ACS, but we can refer you.

There is no cure for hepatitis A. You just have to let it run its course. It can take months to fully recover. If you have had hepatitis A, you are immune. You cannot get it again.


If you are a male or transgender person and you have sex with men, we recommend getting vaccinated against hepatitis A and B. This can be done free of charge at the ACS, or for a reduced fee at the STI clinic of the Centre for Sexual Health (GGD Amsterdam), or at a GP.

Need more information?
Our nurses can answer any of your questions.

Hepatitis B
Hepatitis B is a virus that causes inflammation in the liver. It is highly contagious and common in the Netherlands. You get it mainly through sex (in the vagina and anus) without a condom, or via exchange of bodily fluids (semen, saliva and/or blood) through sharing of drug syringes, razor blades or toothbrushes.


Often initially, you will present with little/no symptoms. You may develop symptoms after 2 to 3 months after getting the infection:

  • Fatigue
  • Nausea
  • Pain in the right upper abdomen
  • Flu-like symptoms such as fever, muscle or joint pain and general malaise
  • Spots on the skin or itching
  • Jaundice: the whites of the eyes and skin are yellow
  • The urine is brown
  • The stool is grey-white

Symptoms in chronic hepatitis B infection
Some people do not exhibit symptoms and others get seriously ill. This group of people may develop an ongoing infection of the liver.


Acute hepatitis B infection
In acute hepatitis B infection, the virus usually disappears from your body by itself after 6 months. You don’t need treatment. You can then no longer pass it on to anyone else and are henceforth immune to the virus. You cannot be infected again.

Chronic hepatitis B infection
Sometimes the disease does not pass and the virus remains in the body. You will be a carrier all your life. This is called chronic hepatitis B disease. You are contagious throughout your life. You may even die from it. That is why it is important that you should use condoms when you have sex. In a steady relationship, your partner should be hepatitis B vaccinated.
Chronic hepatitis B can cause permanent inflammation of the liver, with a risk of liver damage and liver cancer.

Avoid long-term problems with regular STI testing (Preferably once every three months).

You can fight a chronic infection of hepatitis B with medication. But the effect of these varies from person to person and they can have serious side effects. If you are HIV-positive, treatment for chronic hepatitis is often even less successful. The best thing to do is to prevent hepatitis B.


At ACS, you can be vaccinated against hepatitis B free of charge. We first check that you have not been in contact with the virus before.
After a vaccination, you are protected for your whole life and do not need to be tested again.

Need more information?
Our nurses can answer any of your questions.

Hepatitis C
Hepatitis C, like A and B, is an infection of the liver. Hepatitis C is highly contagious and is transmitted mainly through blood-to-blood contact. This blood need not always be visible; minor damage to the mucous membrane of the anus often occurs when fisting, during prolonged anal sex or when dildos and other sex toys are used. Sharing snuff or needles when ‘shooting up’ (injecting drugs) can also transmit the virus. In some cases, the virus can also be transmitted through semen.

Hepatitis C can survive outside the body for up to 6 weeks on materials such as steel, plastic, rubber and in lubricants. Hepatitis C can therefore be transmitted if toys or used gear are not carefully cleaned and disinfected before, during and after sex. Hepatitis C can enter the body through damaged mucous membranes, small wounds or sores.

If you are HIV-positive and take medication for this, you are at greater risk of contracting hepatitis C and are more likely to suffer later consequences such as liver disease and liver cancer.


An acute infection with Hepatitis C is serious; you may feel very ill. Most people have no or only mild symptoms, such as:

  • Fatigue
  • Flu-like symptoms such as fever, muscle or joint pain and general malaise
  • Nausea
  • Pain in the right upper abdomen
  • The urine is brown
  • The stool is grey-white

These symptoms may persist for 3 to 12 weeks and usually go away on their own.


Without treatment, 10-40% of people get rid of the virus on their own, which can take several months (up to 2 years).

Some can develop a chronic hepatitis C infection. People who are HIV-positive are less likely to clear the infection on their own; in 80% of cases they develop a chronic infection. Those with the chronic infection may experience fatigue and general malaise, but the majority hardly have any symptoms. However, untreated chronic hepatitis C infection can later lead to liver disease and liver cancer.

Unlike hepatitis A and B, you can get hepatitis C multiple times, so you do not become immune to it after infection.

Get tested regularly for hepatitis C. Do this every three to six months if you are HIV-positive. Test in between if you think you have been at high risk.

Chronic hepatitis C infection can be treated with antiviral drugs. Usually, such treatment lasts 8-12 weeks. It is possible to be completely cured of hepatitis C by this treatment.


There is no vaccination against hepatitis C. Prevent hepatitis C infection by using condoms during anal sex and toys. When fisting, use latex gloves and do not share lubricant. Clean and disinfect hands, penis, anus, used toys and paraphernalia thoroughly every time you change partners.

More information?
Our nurses can answer any of your questions.

HIV is a virus that invades and destroys your cells, weakening your defences. You can get HIV through sex without a condom (in vagina and anus) and there is a small risk when swallowing semen during blowjobs. You can also get HIV through blood—open wounds or sores, by sharing drug syringes or through a tattoo or blood transfusion abroad (where blood is often not tested for HIV, or where it is not hygienic).


If you have contracted an HIV infection, it does not always cause immediate symptoms. There may be flu-like symptoms after 1 to 6 weeks. You will then have an acute HIV infection. Early signs include:

  • Fever
  • General malaise (headache, sore throat, muscle aches)
  • Skin rash

Not everyone recognises these complaints and symptoms as an indication of HIV. So it is important to remain alert to your body and what it is telling you. These complaints may disappear on their own in the weeks after contracting the infection—but the infection remains.


Since there are very few symptoms of a HIV infection, it is often undetected or left untreated. When the amount of viruses increase, however, your immune system is increasingly affected. This may take two years, or even as long as ten years (or more) or as long as ten years or more. Without treatment (taking anti-HIV drugs every day), HIV keeps on reproducing and eventually you have AIDS.

If you have AIDS, these symptoms may occur:

  • Fatigue
  • Unexplained weight loss
  • Fever
  • Night sweats
  • Diarrhoea
  • Shortness of breath
  • Skin rash

With AIDS, your defences become increasingly weakened, making you more susceptible to pathogens (bacteria, viruses and fungi). For example, simple infections like a cold can turn into dangerous, potentially fatal pneumonia.
Because you can be infected with HIV for years without knowing it, it is important to get tested regularly. It can take 6 weeks to 3 months for an HIV infection to show up in the test, so we recommend testing once every three months. If you have had sex without a condom or had a broken condom, please consult with the ACS nurses.

Unfortunately, there is still no cure for the HIV virus and AIDS. However, the HIV virus can be effectively suppressed with medication (HIV inhibitors). This can prevent you from getting AIDS, common symptoms and from transmitting the virus to others. Many continue to live a good life with HIV successfully suppressed. It does not necessarily mean you should avoid having children.

Medication is often also effective even if you now have AIDS. Your symptoms may disappear and you might feel better, but the HIV virus will remain in your body for life. Treatment of HIV and AIDS always takes place in a HIV treatment center (usually a hospital), under the supervision of a doctor.

You can maintain your immunity (as much as possible) by starting treatment with HIV inhibitors as soon as possible. This treatment ensures that your immune system is allowed to recover as best as possible, and patients reach their golden years! Another advantage of treatment is that given you always use a condom during sex, you will avoid passing on to others.


There is no vaccine against HIV yet, but for some target groups there are PrEP drugs to prevent HIV infection.

Want more information about the HIV virus, AIDS and medication?
Our nurses can answer any of your questions.

Genital warts (HPV virus)
Genital warts are caused by types 6 and 11 of the HPV virus. There are many different types of this virus. The HPV virus is very contagious and can be contracted through sex (penetration), but also through direct contact of the genitals, i.e. when they rub against each other. The virus can also be transmitted through fingers or a used towel.

  • Warts around or on the penis, vulva or anus
  • Warts in the vagina or on the cervix (you cannot see these yourself)
  • Warts in the anus
  • Itching, pain, burning sensation

Not everyone who contracts the virus gets warts. You can still pass on the virus.


Genital warts are harmless. However, they can spread and grow. Not everyone likes this and it can affect how comfortable you feel during sex. It is therefore a good idea to treat the warts.

No test is necessary. A physical examination by a medical professional suffices for the diagnosis.

Do you think you have genital warts?


The HPV virus usually disappears on its own. However, this can take years. You can speed up this process by treating the warts yourself with a cream. Speak to your chemist about the right type of cream. The cream creates an irritation at the site of the wart and jumpstarts your immune system to clear the HPV virus.

If the warts are in an awkward or non-visible part of your body and it is not easy for you to treat it yourself, the doctor will treat the warts by freezing them. Sometimes, it is necessary to remove it with surgery, but only a local anaesthetic is needed.


Do you have genital warts? Be careful when shaving, as this can spread the virus across your skin and cause more warts. There are several vaccines against the HPV virus, including one that protects against the variants of HPV that cause genital warts. Unfortunately, these vaccines are not free. ACS nurses can give you more information about these vaccinations.

HPV and the risk of cancer

There are also variants of the HPV virus that increase the risk of cancer of the cervix, vulva, vagina, penis, anus, mouth and throat later in life. There are also vaccinations against these variants. Even if you have had the HPV virus, there is wisdom in being vaccinated.
In the Netherlands, all women aged 30 and over with a vagina and uterus are advised to have a PAP smear of the cervix every five years to prevent cervical cancer.

Need more information about the HPV-virus?
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Genital herpes
Genital herpes is caused by the herpes simplex virus (HSV). This virus can occur not only on the genitals, but also on the mouth (cold sores). Then it is called ‘herpes labialis’. The virus is very contagious. You can catch it through kissing, oral sex, penetration and by direct contact of the genitals (rubbing together) with someone who is a carrier of the virus. You can also transmit it with your fingers. Blow jobs and licking can also be the cause of the virus being passed on.

The risk of infection is greatest when someone has blisters or open sores. This is because the blisters contain fluid with many virus particles. Condoms do not grant 100% protection against herpes as the blisters often appear in places not covered by the condom—on the lips, around the vaginal opening or anus or at the base of the penis.

Always check if your client is free of cold sores.


Most people who have the herpes virus have no symptoms and do not know they have been infected. If you do develop symptoms, it is usually a week after being infected. Usually, a herpes attack (outbreak) begins with fever and muscle aches. You feel flu-like. After one or two days, symptoms will appear, such as:

  • Painful moist blisters/sores on or near the penis, vulva, around the anus or on the mouth
  • Painful fluid blisters that you cannot see (in vagina or anus)
  • The fluid blisters may itch
  • Difficulty/pain when urinating or defecating
  • Swollen glands in the groin
  • Inflammation in the urethra (of the penis)

The blisters and sores slowly dry out, forming scabs. After about three weeks, these spots usually recover. Only when you no longer can see the spots, are you no longer contagious.


Most people become infected with genital herpes at least once. Unfortunately, there is no treatment against an attack (outbreak) yet.
You are more at risk when you have less resistance (e.g. if you are ill, stressed, haven’t slept enough or have taken a lot of drugs/alcohol). Hormones can also have an impact. Some women are more susceptible around their periods.
The first time you have an attack, symptoms are greater. The attacks after that are usually (increasingly) milder.

You can only test herpes the moment you have blisters. A medical professional will be able to recognise herpes from a visual examination. The fluid in the blisters can be tested with a cotton swab. If you have wounds or blisters, or you have had sex with someone you suspect had herpes, contact ACS by phone as soon as possible to make an appointment or consultation.


The blisters or sores will go away by themselves. To deal with pain and irritation, there are creams that speed up the drying out period. There is also medication to provide temporary numbing, especially if urinating or defecating is very painful.

It is possible to take antiviral drugs that will make your symptoms less severe and long-lasting. You can also take medication for a longer period that suppresses the virus somewhat. For those with at least six attacks a year, this can provide relief.

Need more information about genital herpes?
Our nurses can answer any of your questions.

Vaginal discomforts
Individuals with vaginal discomfort can also experience symptoms that are not caused by an STI, but by a disruption in the natural balance of the vagina. If you suffer from this, there is a greater risk of you contracting an STI.

Bacterial vaginosis

Bacterial vaginosis is a disturbance of the acidity of the vagina. This allows the bacterium gardnerella vaginalis, naturally found in the vagina to grow excessively. The cause often remains unknown, but sometimes it can be due to:

  • (Internal) Douching the vagina with soaps
  • Medication use
  • Sex (too dry or lubricant or condom that reacts with your PH levels/comfort)
  • Having a menstruating sponge or tampon in for too long
  • More discharge, often more watery and greyish-white in colour
  • Smellier discharge (often fishy)
  • If the discharge comes into contact with semen, the smell becomes even stronger
  • Pain or some bleeding during sex
  • Slight nagging pain in the lower abdomen
Candida (vaginal yeast infection)

Candida is yeast (a type of fungus) that normally lives on skin and inside the body. It can be found in the mouth, throat, gut, and vagina. Normal, healthy levels is expected and does not cause problems. However, when the balance in the vagina is disturbed, candida can grow excessively. The cause of a vaginal yeast infection often remains unknown, but sometimes it can be due to:

  • Antibiotic use
  • Stress
  • Reduced immunity
  • Hormonal changes, for example around your period
  • Wearing clothes or thongs that are too tight. (Candida actually feels very much at home in warm and humid places)

Complaints that are part of a candida-infection:

  • Itching in the vagina and/or vulva
  • Redness and swollen vulval lips
  • Discharge like white cottage cheese or yoghurt
  • Pain during sex and urination
  • A somewhat sour smell

The ACS only tests for bacterial vaginosis and candida when you have symptoms of these. Do you have complaints?


Bacterial vaginosis is easy to treat with antibiotics. We will give you a prescription for this. A candida infection can be treated well with a vaginal cream and vaginal capsules. These two remedies are also available without a prescription at the chemist.

Please note that use of these medications can affect the effectiveness of the condom for up to three days. So, it is better not to work until you are well. This will also give your vagina chance to rest and heal properly.

If your yeast infection is persistent, do consult a doctor.

Need more information about vaginal discomforts?
Our nurses can answer any of your questions.

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