Mpox is caused by an orthopoxvirus that occurs primarily in countries in West and Central Africa. In spring 2022, the disease was detected in people in Europe who had no direct connection to those areas in Africa. The disease then spread in Europe, North America and in other areas than where it originated. After a spike in the summer of 2022, the number of reported cases declined sharply in the fall of 2022.

Monkeypox is now called mpox

The World Health Organization (WHO) announced a new name for the infectious disease monkeypox in late November 2022. This is because the original name led to racist and stigmatising comments in many countries around the world. Therefore, the WHO came up with a new, neutral name: mpox.

What is mpox?

Mpox, also known as monkeypox,  is a viral infection that originally occurred mainly in West and Central Africa. Sometimes a traveller from that region will carry the disease to Europe. It is a zoonosis (a disease that can be transmitted from animals to humans) that mainly comes from rodents in Africa. The course of illness is usually mild in humans, but can cause great pain and leave permanent scars. The word ‘monkeypox’ is often used for impetigo on the islands of Aruba, Bonaire and Curaçao and in Suriname.

Infection mpox

As of 6 September 2023, there were 1,274 confirmed cases of monkeypox in the Netherlands. 

Reported cases of monkeypox

Skip chart Reported cases of mpox in the Netherlands and go to datatable

There is a delay of a few days between the moment that a person shows symptoms of mpox for the first time (the first day of illness) and the date that this person is reported to the Municipal Public Health Service (GGD). Therefore, there are usually no reported cases of people with a first day of illness shortly before the latest update of the figures.

Symptoms of mpox

The symptoms of an infection with the mpox virus are similar to smallpox, but mpox generally causes a much milder course of illness. The most important symptom is the skin rash, which can present as red spots, bumps or lesions. These bumps or lesions eventually form the blisters, which can be painful. The blisters dry up and form a crust, leaving scabs that eventually fall off two to three weeks later. The blisters may leave scars.

Other general symptoms that are associated with mpox include:

  • fever
  • headache
  • muscle ache
  • swollen lymph nodes 
  • chills
  • tiredness

Some cases of mpox start with general symptoms followed by the skin rash, while others start with the rash and then develop other symptoms. A number of people in the current outbreak have also had proctitis, a painful inflammation of the lining of the rectum (the final part of the intestines). Sometimes proctitis is the only symptom.

Pictures of mpox

Phase 1

Monkeypox (apenpokken) op vinger, fase 1

Mpox on finger, phase 1

Phase 2

Monkeypox (apenpokken) op vinger, fase 2

Mpox on finger, phase 2

Phase 3

Monkeypox (apenpokken) op vinger, fase 3

Mpox on finger, phase 3

How the mpox virus spreads

More and more confirmed cases of mpox have been found in the Netherlands. Anyone can get mpox, and infections with the virus occur in all age categories. Most of the recent infections so far have involved MSM contact (men who have sex with men). The highest risk of infection is among men who frequently have sex with multiple partners. Mpox is transmitted through intimate contact (kissing, making love and sexual intercourse) with someone who is infected. Very occasionally, the virus is also transmitted through unprotected contact with contaminated materials (such as bedding). The virus can enter the body through the mucous membranes or through tiny wounds or tears in the skin. The virus can also spread via droplets of fluid from the blisters or from the mouth and nose, although this risk is currently considered low.

You may already be contagious before developing any visible symptoms. Some people develop flu-like symptoms or a skin rash before the blisters appear. Blisters may also form in less visible locations, such as in your mouth or inside the rectum, where they may resemble ulcers. Some people with mpox only have 1 blister. The scabs from the blisters can also transmit the virus.

close-up van een pok (apenpokken)

Close-up of a mpox lesion

Preventing infections

There are various ways to prevent infection. Do your part to stop mpox. You can avoid or minimise high-risk contacts to reduce your risk of getting monkeypox. Less contact involving sex and cuddling lowers the risk of infection. Quickly recognising symptoms that could indicate mpox is another way to prevent exposure to the virus. If you or someone else may have been infected, it is important not to have sexual intercourse or any intimate contact – not even with a condom. Also, make an appointment with the Municipal Public Health Services (GGDs) or your GP to get tested for Mpox as soon as possible.

If you test positive for Mpox, the GGD will start source and contact tracing. Contacts who have a high risk of exposure to a person infected with mpox are eligible for a vaccination. Vaccinating people who have MSM contact and a higher risk of Mpox exposure also helps to prevent transmission of the virus. However, further research is still needed to determine the extent to which the vaccine protects against mpox. For that reason, it is important to follow the recommendations to prevent infection even after vaccination.

Source and contact tracing

If a person tests positive for mpox, the Municipal Public Health Service (GGD) starts source and contact tracing. The aim is to find out the source of the infection and whether the infected person has been in contact with others. It is important to take part in source and contact tracing. The sooner the GGD can notify people who have been in contact with an infected person, the more likely it is that potential new infections can be prevented. This is especially important because the incubation period seems to be about 8.5 days on average at this point, but it may be as long as three weeks before someone starts showing symptoms. 

Source and contact tracing differentiates between low, medium and high-risk contact with an infected person. Specific rules apply to the different risk groups. After consulting with the GGD, high-risk contacts may be eligible for vaccination as a form of post-exposure prophylaxis (PEP).


If you test positive for mpox, you need to self-isolate (stay at home) and follow the rules for isolation. You should not have any contact with others until all your symptoms are gone. In the context of mpox, that means that all the scabs from the blisters must have fallen off and new, healed skin must have formed.  This is because it is also possible to catch the virus from contact with the scabs. The rash often persists longer than any other symptoms.  If you also have proctitis (inflammation of the lining of the rectum), all the symptoms associated with proctitis, such as anal discomfort, must also have resolved completely.


In the efforts to control the mpox virus, RIVM is working closely with Soa Aids Nederland and the regional Municipal Public Health Services (GGDs), including the Centres for Sexual Health. RIVM provides guidelines for diagnostics, source and contact tracing and general medical information. RIVM also provides information about the vaccine and the vaccination and informs the GGDs about implementation of the mpox vaccination. RIVM activities also include arranging transport and distribution of the vaccines and registering data about mpox vaccination for monitoring and research purposes. The Municipal Public Health Services (GGDs) are the regional coordinators of the mpox vaccination programme. Soa Aids Nederland maintains close contacts with the target audience and other stakeholders and is handling outreach and information about how to prevent infection with the mpox virus.

DNA of monkeypox virus in sewage

Sewage can serve as an indicator of public health in the Netherlands. Many diseases that occur within a group of people can be detected in sewage. RIVM is therefore conducting research into the monkeypox virus in sewage. Read more about the monkeypox virus sewage research.

Frequently asked questions about mpox