The symptoms of tularaemia

There are different types of bacteria that cause the disease tularaemia. Not everyone who gets infected with the bacteria develops symptoms. Whether someone gets sick depends on:

• the type of bacteria
• the method of contamination (e.g. through the skin, inhalation or food)
• how many bacteria have entered the body
• a person's immune system

The disease has different forms. Most people get sores on their skin after touching infected dead animals or from the bite of an infected insect.

The disease usually starts with:

• fever
• headache
• muscle ache
• cold chills
• sore throat (uncommon)

Within 24 to 48 hours, an inflamed blister appears at the location of the infection. This is usually on a finger or arm, in an eye, or on the palate. Other possible symptoms include:

• swollen lymph nodes
• throat infection (laryngitis)
• eye infection (conjunctivitis)
• pneumonia
• severe abdominal pain and diarrhoea

After an infection, people become ill after 1 to 21 days. In most cases, it takes 3 to 5 days.

The disease is rare and the symptoms are similar to those of other diseases. That is why a doctor often does not immediately think of tularaemia.

People with weak immune systems can get very ill from tularaemia

People whose immune system does not work properly are at risk of becoming more seriously ill than healthy people.

How can I get tularaemia?

In the Netherlands, the risk of getting tularaemia is very small. People who come into frequent contact with wildlife, such as hunters, butchers, farmers and some laboratory workers, are at greater risk. A person may get tularaemia from:

• Contact with infected animals, e.g., a shot hare. The bacteria can penetrate through damaged skin.
• A bite from an infected horsefly, mosquito or tick.
• Eating contaminated food, such as contaminated meat that is not properly cooked.
• Drinking contaminated water.
• Inhalation of the bacteria through dust. For example, dust from mowing.
• Contact with the bacteria in the laboratory without proper precautions.

The bacteria can also infect dogs or cats. Transmission of infection from a dog or cat to a human is rare. Humans cannot infect each other.

How to prevent tularaemia?

There is no vaccination to prevent tularaemia. The bacteria can survive for a long time in a cool, humid environment. The recommendations below reduce the risk of the disease. 
In nature:

• Do not touch wild hares or rodents; if you must touch them, wear gloves.
• Avoid bites from insects and ticks:
  • Wear solid shoes, long sleeves and long trousers. Tuck your trouser legs into your socks.
  • Apply an insect repellent containing DEET to uncovered skin.
  • Check regularly for tick bites. Remove ticks quickly and carefully.
  • Do not drink surface water (rivers, ditches, lakes) and avoid contact with surface water.

Also:

• Wear gloves and a face mask when working with dead animals that may be contaminated or if you perform activities that generate a lot of dust (e.g. mowing).
• Cook game meat thoroughly. Freezing animals or meat does not kill the bacteria.

Someone who has had tularaemia does not get the disease again.

How to treat tularaemia?

Tularaemia is treated with antibiotics. Patients can have symptoms for weeks, but most people completely recover with antibiotics. If the GP suspects that someone has tularaemia, it is important to have (laboratory) tests done.

How often does tularaemia occur?

In the Netherlands, tularaemia first occurred in 1953, but not for years after that. Since 2011, the bacterium has been occasionally found in humans and hares. A total of 39 people with tularaemia were reported from 2011 to 2024. This varied from 0 to 9 patients per year, across the country. Eight people were probably infected abroad. Extremely rarely have multiple people become ill from the same source; this only occurs sometimes within families.

The bacterium that causes tularaemia is found in the Northern Hemisphere. In Europe, the disease is most common in Sweden and Finland. The type of bacteria in North America differs from that in Europe and Asia. The type in North America makes people ill more easily and more severely.