Introduction

Tularemia is known as a “zoonotic disease”.¹ This means that it is passed from an infected animal to humans.¹

It is not very common, as fewer than 300 people were found to have Turalemia per year in America.¹ However, it has been found in America, Russia and Europe,² and the disease is very infectious, which means that it only takes a very small sample of the bacteria to make someone very ill.¹ This means that understanding the symptoms and treatment of Tularemia is very important.

What is tularemia?

Tularemia is a disease that humans catch when they come into contact with F. tularensis bacteria.¹ This contact can be by:¹

• Breathing in the bacteria from the air
• Being bitten by either an infected animal or a tick 
• From eating contaminated food
• Drinking drinks with F. tularensis in them
• From touching infected animals

Inside everyone’s body, there are “immune cells” which help to fight infection.³ These cells are part of your immune system, and they usually absorb bacteria to break them down so that they cannot hurt you.³ However, F. tularensis bacteria do not die when they are consumed by immune cells.¹ Instead, it multiplies inside them, and eventually the immune cells break, letting the bacteria back out into your body in large numbers.¹ This can make you very ill.

Tularemia symptoms usually appear between three to five days after the person has had contact with the bacteria, though it can take up to a fortnight before symptoms become noticeable.¹

How is tularemia treated?

If you think that you or someone you know has Tularemia, the affected person should see a doctor straight away.¹

Fortunately, Tularemia is curable in humans.¹ Your doctor will give you antibiotics, either in tablet form or by injection, and this will help you fight off the infection.1 If you have other symptoms due to Tularemia, they may treat these with other methods.¹

The medicines most commonly given for Tularemia are:¹

• Levofloxacin
• Gentamicin
• Ciprofloxacin
• Streptomycin
• Azithromycin
• Doxycycline

Who is at risk of tularemia?

People who spend a lot of time with animals are the most likely to get Tularemia.¹ This means you have a higher chance than average of catching it if:¹

• You are a lab worker who works with F. tularensis
• You hunt or cook game
• You work on a farm
• Work with animals, e.g., as a zookeeper or vet
• You have a reduced immune system (eg, you are taking immunosuppressants or have a disease like HIV)
• You live or work around insects that bite

Types of tularemia

There are different kinds of Tularemia that people can have, usually depending on how they caught it.¹ These types are listed below.

Typhoidal tularemia

This kind of Tularemia occurs when the person has a high temperature or fever.¹ People with this type of infection usually report a high temperature, being disoriented, experiencing chills, nausea and/or vomiting, being unable to eat, diarrhoea, aching muscles, stomach pain, and a sore throat.¹ 

Ulceroglandular tularemia

This is the most common kind of Tularemia that humans get.¹ It happens when the person is bitten by an animal that has Tularemia or by an infected tick. People with this form of Tularemia experience symptoms in their skin and their lymph nodes (glands which are an important part of your immune system).⁴ 

The symptoms of this form of Tularemia are an ulcer or sore on the skin, usually at the point where the bacteria got into the body (eg, via a bite), high temperature and swollen and sore lymph nodes.¹ 

Pneumonic tularemia

Pneumonic Tularemia is the most life-threatening form of Tularemia, though it is still treatable with antibiotics.¹ It is either caused by breathing in the bacteria or if you caught the disease another way (for example, by a bite), and then the bacteria spread to your lungs.¹

If you have this kind of Tularemia, the symptoms usually present as a cough which may involve bringing up blood, a high temperature, a rash on the skin, being unable to catch your breath, aching muscles and pain or a feeling of tightness in the chest.¹

Glandular tularemia

This is another kind of Tularemia that is caught by an infected animal or a tick bite.¹ However, this kind of Tularemia only affects your lymph nodes and not your skin.¹

The common symptoms of glandular tularemia are swollen, painful lymph nodes and high temperature.¹

Oropharyngeal tularemia

This type of Tularemia is caught by eating or drinking something with Tularemia bacteria on it, or by touching something with Tularemia bacteria on it and then touching your face.¹

Symptoms of oropharyngeal tularemia can include: pain in the stomach, high temperature, diarrhoea which may have blood in it, a sore throat which may have swelling and white patches inside and vomiting.¹

Oculoglandular tularemia

People with this kind of Tularemia have caught the bacteria when the bacteria have got into their eyes.¹ It usually only happens in one eye while the other is fine, but if both eyes have had contact with the bacteria, then it can be present in both.¹

If you have this kind of tularemia, you may have an ulcer on your cornea, pain in the eyes, pain and swelling in the lymph nodes of your neck and ears, watering eyes, and pain when you are around bright lights.¹

Tularemia in children compared to adults

It is more common for children to experience the glandular form of Tularemia, whereas in adults, it is more common for the ulceroglandular form to be found.⁵ This may be due to the skin ulcers common in ulceroglandular tularemia being missed and so going unnoticed.⁵

Some studies suggest that Tularemia may be more severe in children, though this may be because of how long it took for the children to be diagnosed with Tularemia.⁵

Other studies have found that children with Tularemia are more likely to have a high temperature, tiredness, a sore throat, and problems with their liver and spleen than adults with Tularemia.⁶ 

How is tularemia diagnosed?

When you see your doctor, they will do some tests to try to work out what is causing your symptoms. They will carry out several tests.

Taking your medical history

Your doctor will ask you about your symptoms, including how long you have had them and how much they are affecting you.¹ They may also ask if you have been in contact with any raw meat or animals that may have been ill, and how long ago any contact may have been.¹

Physical examination

Your doctor will usually ask to check you to check your problems for yourself. This may include:¹

• Checking your lymph nodes, both by looking to see if they are swollen and by feeling them to see if this causes you to feel any pain or discomfort
• Checking your throat and mouth if you have a sore throat
• Checking your eyes to see if you have a corneal ulcer 
• Looking at your skin to examine any ulcers or rashes you may have noticed

Blood tests

One of your medical team members will take a small amount of blood from your arm to be sent to a laboratory and examined.⁷ This will let them see if F. tularensis or any other bacteria are present in your body.¹ 

Biopsy

Your medical team may take a tissue sample from the affected area, e.g., your skin or lymph node, to be sent to a laboratory and tested.⁸ This lets them assess if there is F. tularensis bacteria present.¹

Swab test

Your doctor may use a tool similar to a cotton bud to get a sample of mucus from your throat or nose if these have been affected.1 This sample will then be sent to the laboratory for testing to see if any bacteria are present that could be making you ill.¹

Thoracentesis 

If you have pneumonic tularemia, you may need thoracentesis.¹ This is when your doctor will send you to the hospital so that a specially trained doctor can use a needle to remove fluid from the wall of your chest and the outside of your lung.⁹ 

After this procedure is done, some of the liquid that was removed can be sent to the lab and tested for bacteria.

Preventing tularemia

There are many ways you can reduce the chances of catching tularemia. These include:¹

• Use an oven to cook meat, rather than a barbecue, and always follow cooking instructions
• Wear long sleeves and trousers while walking outside, especially if you are in areas with forests or long grass. This will help you avoid ticks.
• Wear insect repellent
• Do not use a lawn mower around any dead animals. Running over a carcass with lawnmowers can cause bacteria that were in the animal to vaporise into the air, letting you breathe it in.
• If you have been walking in places where ticks may live, check yourself and your family and your pets once you get home in case you have been bitten.
• Do not eat or drink anything that may have been contaminated by bacteria
• Wear gloves if you ever have to deal with dead animals, and wash your hands carefully afterwards
• Clean surfaces and cutlery after preparing meat

Summary

Tularemia is a serious zoonotic disease caused by Francisella tularensis. It is transmitted through animal bites, tick exposure, contaminated food or water, or inhalation. This condition can infect various parts of your body and can lead to different forms, such as ulceroglandular, pneumonic, and glandular tularemia. Common symptoms of tularemia include fever, swollen lymph nodes, ulcers, or respiratory issues. Tularemia can be treated with antibiotics like oxytetracycline or ciprofloxacin. In order to lower the risk of infection, preventive strategies include wearing protective clothing outside, avoiding contact with dead animals, applying insect repellent, and properly cooking meat. If you think you or someone you know has tularemia, you should make an appointment with your doctor immediately.