Malaria is a disease caused by parasites. These parasites may enter your body when you are being bitten by a mosquito. Malaria causes fever, headache, chills and muscle ache. Malaria is seen regularly in the Netherlands, in people who have contracted the disease in the tropics or subtropics.

What is malaria?

Malaria is caused by infection with the Plasmodium parasite. There are various types of Plasmodium parasites that may cause people to fall ill, the most common of which are Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale and Plasmodium malariae. The first symptoms of the disease typically occur some 10 to 14 days after being bitten by an infected mosquito. The parasites of P. vivax and P. ovale pass through a stage (hypnozoites) during which they lie dormant in the patient’s liver. Such parasites sometimes do not become active and cause symptoms until months or even years after the initial infection.

Malaria symptoms

Symptoms include fever, chills, muscle ache and headache, often preceded by flu-like symptoms. Infection with P. vivax or P. ovale is characterised by bouts of fever recurring every 48 hours (tertian malaria), while infection with P. malariae results in bouts of fever recurring every 72 hours (quartan malaria).

How to prevent being infected with malaria

Malaria is transmitted through the bite of female Anopheles mosquitoes. These mosquitoes are active between sunset and sunrise. The parasite cannot be transmitted directly from human to human. Malaria prevention measures are focused on travellers who are going to or have just come from a risk area for malaria in the tropics or subtropics. Malaria infection can be prevented by taking an anti-malarial drug. Such drugs prevent severe falciparum malaria caused by P. falciparum. The risk of infection can also be reduced by wearing clothes that cover one’s entire body and by using mosquito nets and mosquito repellent during those times of the day when mosquitoes are active.

How common is malaria in the Netherlands?

Each year some 150 to 300 cases of malaria are reported in the Netherlands (Figure 1). The majority of these are caused by infection with P. falciparum. Every once in a while, infections with other types of malaria or mixed infections with the aforementioned Plasmodium types are reported. The current malaria situation in the Netherlands is presented in the Atlas Infectieziekten [Infectious Diseases Atlas]. 
[mixed infection or unknown]

Figure 1. Annual number of malaria cases reported in the Netherlands by type of Plasmodium, 2007-2017.