Brucellosis

Overview

Brucellosis is a bacterial infection that can spread from animals to humans. It often causes a fever that comes and goes, along with joint pain and tiredness. It is also called undulant fever or Malta fever.

In the UK, brucellosis is very rare — fewer than 10 cases are reported each year. Worldwide, however, it is one of the most common infections passed from animals to people.

It mainly affects people who work closely with livestock, such as sheep, cattle, goats, pigs, and dogs. Travellers who visit countries where the infection is common can also get it, especially if they eat unpasteurised dairy products.

Symptoms

Common symptoms

• Fever that comes and goes, often higher in the evening
• Heavy sweating, sometimes with a musty smell
• Headache
• Joint and muscle aches
• Feeling very tired or weak
• Loss of appetite and weight loss
• Stomach pain or discomfort

Symptoms in children

• Fever, often with chills
• Tummy pain
• Poor feeding or loss of appetite in younger children
• Being unusually fussy or irritable
• Tiredness and not wanting to play

Symptoms in older adults

• Persistent high fever
• Severe tiredness and weakness
• Joint stiffness, especially in the hips, knees, or back
• Confusion or trouble concentrating
• Symptoms that can be mistaken for flu or other age-related conditions

Causes

Main causes

• Infection with bacteria of the Brucella species
• Drinking unpasteurised milk or eating cheese and other dairy products made from it
• Direct contact with infected animals or their blood, urine, or birthing fluids
• Bacteria entering through cuts or grazes in the skin when handling animals
• Breathing in dust or particles contaminated with the bacteria on farms or in laboratories

Risk factors

• Working as a farmer, shepherd, vet, or abattoir worker
• Travelling to regions where brucellosis is common, such as parts of the Mediterranean, Africa, Latin America, and Asia
• Eating raw or unpasteurised dairy products while travelling
• Working in a laboratory that handles Brucella bacteria
• Hunting or handling wild animals that can carry the infection, such as wild boar or bison

When to see a doctor

See a doctor urgently if:

• You have a fever with a severe headache and a stiff neck
• You feel suddenly weak, confused, or have trouble speaking
• You have breathing problems or chest pain

Book a routine appointment if:

• You have a fever, heavysweats, or unusual tiredness that lasts longer than a few days
• You have new joint or muscle pains without a clear reason
• You have recently travelled to a country where brucellosis is common or worked with animals

Diagnosis

A doctor will ask about your symptoms, any animal contact, and travel history. Because brucellosis is rare, they will also rule out more common causes of fever. Diagnosis is confirmed with blood tests.

Tests that may be done

• Blood test to look for antibodies against the bacteria
• Blood culture to try to grow the bacteria from a sample
• Sometimes a bone marrow or fluid sample if the infection is hard to find
• Repeated blood samples, because the bacteria can be difficult to detect at first

What to expect at your appointment

You may need to give several blood samples over a few days or weeks. Results can take a while because the bacteria grow slowly. If brucellosis is diagnosed, you will usually be referred to an infectious disease specialist.

Treatment

Brucellosis is treated with antibiotics. The full course takes several weeks, and it is very important to finish all the medicine even if you start feeling better earlier. Your doctor will monitor you to make sure the infection has cleared.

Self-care at home

• Get plenty of rest, especially when you have a fever or feel exhausted.
• Drink enough fluids to stay hydrated.
• Use a cool cloth or fan to help bring down a high temperature.
• Take over-the-counter fever or pain relief that your pharmacist or doctor recommends — but check with them first, especially if you have other health conditions.

Medical treatments

A combination of antibiotics is usually prescribed for at least six weeks. The exact plan depends on your age, health, and how severe the infection is. It is important to complete the entire course to stop the infection from coming back. Your doctor may also arrange follow-up blood tests to confirm the bacteria are gone.

When is surgery considered?

Surgery is not usually needed for brucellosis. In rare cases, if the infection causes an abscess in an organ or around a joint, a procedure might be required — but this is uncommon.

Living with this condition

During treatment, you may feel tired and unwell for weeks. Allow yourself time to recover, and gradually return to your normal activities as your strength improves. If you work on a farm or with animals, tell your doctor — you may need to stay away from certain tasks until the infection is cleared.

Lifestyle tips

• Keep all medical appointments and finish your full course of antibiotics.
• Take time off work if you feel too unwell; ask your doctor for a sick note if needed.
• Wash your hands well after handling animals or animal products.
• Avoid unpasteurised dairy products, especially while travelling.
• Talk to your doctor before getting any vaccinations while you are still ill.

Diet and exercise

Eat a balanced diet to help your body recover. Gentle exercise, like short walks, can help with energy and mood, but rest when you feel feverish or exhausted. Listen to your body and don't push too hard.

Mental health and emotional wellbeing

Living with a long infection can feel frustrating and isolating. It is normal to feel low, anxious, or worried. If these feelings last or affect your daily life, speak to a healthcare professional — they can offer support and can refer you for talking therapy if needed. If you are in crisis, reach out to your local emergency mental health services.

Prevention

Yes. The simplest way is to avoid drinking unpasteurised milk or eating unpasteurised dairy products, especially while travelling. People who work with animals should wear protective gloves, eyewear, and cover any cuts, and follow farm hygiene practices like washing hands and equipment thoroughly.

Vaccines

There is no vaccine for humans. Vaccines are available for animals in some countries, but they are not used in the UK.

Screening programmes

Routine screening is not normally offered. Workplaces with high exposure risk, such as veterinary laboratories, may have their own health checks — ask your employer or occupational health team for details.

Complications

If left untreated

• Long-term, recurring fever and exhaustion
• Joint damage, especially in the spine, hips, and knees
• Inflammation of the heart lining (endocarditis)
• Inflammation of the liver or spleen
• Rarely, infection of the brain or the tissue around it

Long-term outlook

With early treatment, most people with brucellosis recover fully. The infection may take several weeks to clear, and some people feel tired for a few months afterwards, but serious problems are uncommon when the full antibiotic course is taken. Follow your doctor's advice and you can expect your health to keep improving.

Find support

External links open third-party websites. Ruqelo Health is not responsible for external content. Listing an organisation does not imply endorsement.