How do I recognise the symptoms of leishmaniasis?

Many people carry the parasite without noticing it. Some people do get symptoms. The symptoms of leishmaniasis in humans depend on the place in the body where the parasite causes disease and the type of parasite. Patients may have leishmaniasis on the skin, on the mucous membranes, or in the organs in the abdomen.

Leishmaniasis on the skin (cutaneous leishmaniasis) is the most common. This creates sores where the infected sandfly has stung. The sores can spontaneously disappear after months or years. These places can become severely scarred.

Leishmaniasis on the mucous membranes first produces a skin sore. Next, the patient develops sores, especially on the mucous membranes of the mouth or nose. These can deform the entire face.

Leishmaniasis in the organs in the abdomen (abdominal leishmaniasis) is also called kala-azar ('black fever'). This causes the spleen and liver to expand. Other symptoms include:  

• anaemia
• tiny bleeding spots in the mucous membranes
• spots on the skin
• weight loss
• long-term fever
• feeling ill
• diarrhoea
• occasional coughing

Once people get sick with abdominal leishmaniasis, it is almost always fatal unless treated. However, there are also people who have no or only mild symptoms with this form of leishmaniasis. It depends on the person's immune system. If their immune system deteriorates later, that person could become seriously ill.

Animals can also get leishmaniasis. Dogs in particular can get sick, but also many other animals, such as rodents, cats, sheep and goats. In dogs with abdominal leishmaniasis, the disease symptoms are similar to those in humans. Dogs also often suffer from weight loss, hair loss around the eyes, muzzle and ear tips, and fast-growing, fragile nails. Cattle can also become infected with leishmaniasis. Cattle exhibit symptoms such as fever, swollen lymph nodes and skin sores.

How do I get leishmaniasis?

The Leishmania parasite is transmitted by the bite of a sandfly. The parasite can be transferred from human to human or from animal to human.  

There are many types of Leishmania, for example, Leishmania infantum. This species also occurs around the Mediterranean, where sandflies transfer the parasite from dogs and rats to humans.  

The time between getting infected and developing symptoms ranges from 10 days to several years. On average, it takes 2 to 6 months from the bite of the sandfly to the onset of symptoms.  

The adult sandflies are hard to see. They are very small (about 1.5 to 3.5 millimetres), do not buzz and their sting is not always noticeable. Most sandflies rest during the day in places with a lot of shade. They are mainly active between sunset and sunrise. They are poor flyers that stay close to the ground. Sometimes the wind carries the sandflies for miles.

How do I prevent leishmaniasis?

There is no leishmaniasis vaccine. That is why it is important to protect people and animals from the sandflies. This can be done with:  

• Protective clothing (long sleeves, long trousers, socks, closed shoes) - especially after sunset
• Insect repellents
• A fine-meshed mosquito net (the flies are 1.5 to 3.5 millimetres in size)
• For dogs: a special collar with insecticides  

The sandflies are mainly active around dusk and are usually found near water (beach, riverbank, lake). They are less often present in homes, where people can control them with insecticides.

Can leishmaniasis be treated?

Leishmaniasis on the skin usually heals itself after 2 to 15 months, but can take longer. There are several treatments to make it heal faster and better. However, it will still take a long time for the sores to heal. The treatment depends on the type of parasite and the symptoms.  

Leishmaniasis on the mucous membranes can potentially cause deadly infections and should therefore always be treated. There are several medicines for that.  

Without treatment, abdominal leishmaniasis is fatal. The treatment given to a patient depends on the type of Leishmania, its side effects and the availability of the medicines plus any other diseases the patient may have.  

How often does leishmaniasis occur?

Leishmaniasis occurs in 88 countries worldwide, especially in tropical regions and around the Mediterranean. In the Netherlands, the disease only occurs in people who have been abroad or have moved from abroad to the Netherlands. Sometimes they do not develop abdominal leishmaniasis until years after their travels. This only happens when their immune resistance is lowered due to another disease or chemotherapy.     

In the Netherlands, there are a number of cases of leishmaniasis each year, imported from abroad in humans and dogs. The disease also occurs in holiday destinations such as Spain, Portugal, Italy and France. In recent years, there have been more cases of leishmaniasis on the skin, particularly in travellers from Spain, Turkey, Morocco and Central and South America.  

The sandfly that transmits Leishmania does not live in the Netherlands. The disease will therefore not spread further in the Netherlands.