Weil’s disease often causes jaundice

Weil’s disease causes jaundice in half of the cases in people who suffer from it. Moreover, this is often accompanied by reduced urine production. But meningitis can also occur due to the infectious disease. But what is Weil’s disease? And why is Weil’s disease becoming more common in modern times? Read all about Weil’s disease.

More Weil’s disease

The GGD in Friesland reported an increase in the number of cases of Weil’s disease in 2014. In 2014, 13 people came to the facility suffering from the disease. Normally there are only between 2 and 4. Nationally too, there were twice as many reports of Weil’s disease in 2014 than in previous years.

Rat disease

Weil’s disease is also called rat disease. This is because the brown rat is the main spreader of the disease. There are also other animals that transmit the condition. These are;

  • Muskrats
  • Field mice
  • House shrews


How do you get Weil’s disease?

Weil’s disease is transmitted when people come into contact with water that contains the disease through the urine of infected animals. The infectious disease is also transmitted through intensive contact with infected animals. For this reason, people who have an agricultural profession are also at greater risk of the disease. Cows in a milking parlor that urinate there and have the disease (they do not have to become ill themselves) can infect the farmer. The striking thing is that animals excrete the bacteria through their urine for weeks to years. This means they can transmit the disease for a very long time. In the Netherlands, there are intensive control programs such as tank milk testing in cows that produce milk and blood testing in cattle for meat. This means that the chance that they can pass on Weil’s disease untreated is small.

Greatest chance of Weil’s disease

People who swim in surface water where rats live are at greatest risk of developing Weil’s disease. If the water is stagnant or flows little and is tepid, that is an even greater risk factor. Then the conditions are very favorable for the bacteria.
Farmers who have contact with infected cows are also at risk, but less than in the past. A third of people who contract Weil’s disease do so abroad where control is much less well regulated and where many rats and mice live. It is therefore important to avoid surface water that hardly flows and to avoid places where many mice or rats are expected to live.

Weil’s disease in dogs

Not only people can contract Weil’s disease, dogs are also susceptible. This is because they:

  • Swimming in open water
  • Licking each other’s genitals
  • Licking up urine



The symptoms of Weil’s disease are diverse. For most people, they first suddenly develop a very high fever. Weil’s disease is often confused with the flu at first. Other symptoms include:

  • Cold shivers
  • Red eyes
  • Stomach ache
  • muscle strain
  • Headache
  • Vomit



Half of the people also develop jaundice and this is often in combination with reduced urine production. The liver and kidneys are severely affected by the disease.


Weil’s disease is treated with antibiotics. People suffering from the disease can make a full recovery if treatment is started on time. But if this is not done, the disease can even be fatal.

Be careful when swimming in non-flowing water or contact with water

Swimming in certain water (where the rodents frequent) or contact with surface water where the animals swim and urinate is the greatest risk factor for developing Weil’s disease. People who become ill with the flu after swimming in open water or having been in frequent contact with water are advised to go to the doctor as soon as possible and report all these facts.

Mice or rat plague

It is not entirely clear why Weil’s disease was much more common in 2014 than in previous years. There is probably a connection with a mouse or rat plague. In Friesland there was a real mouse plague in the southwest of the province in 2014.