Brucella Canis symptoms and what to look out for as three Britons contract bacterial infection from dogs and dog cases skyrocket

For the first time in Britain, three Britons have been infected with Brucella canis – a disease usually restricted to dogs imported from Eastern Europe.

The unidentified cases contracted the bacterial infection after contact with infected pets, with at least one requiring hospital treatment for their symptoms.

But officials also revealed the bug is spreading among British canines for the first time, raising the prospect of further human infections.

A record 91 cases in dogs were discovered in the first six months of this year alone.

Here, MailOnline answers all your questions about the bacterial infection, including how to protect yourself and your pet.

Brucella canis can infect both humans and dogs, but causes different symptoms

What is Brucella canis?

Brucella canis is a bacterial infection that mainly affects dogs.

However, other canines, such as foxes, wolves and coyotes, are also susceptible.

It was first identified in the 1960s after breeders in the US reported that their dogs were having miscarriages.

Brucella canis is considered an incurable disease in dogs and in rare cases can also infect humans.

Although infection is not a death sentence for animals, the bacteria can remain dormant in a dog, meaning the animal is at risk of transmitting the infection to others for the rest of its life.

Historically, the vast majority of cases of Brucella canis in Britain have come from imported dogs, mainly from Eastern Europe where the disease is more common.

However, health chiefs warned this week that the disease is now spreading in Britain.

Does Brucella canis need to be reported in Great Britain?


In 2021, Brucella canis was made a reportable animal pathogen across Great Britain.

This means people are legally required to report a case to the government’s Animal and Plant Health Service.

Even suspected cases of Brucella canis must be reported or people risk legal sanctions from the Department for Environment Food and Rural Affairs (DEFRA).

How do dogs get Brucella canis?

Brucella canis is mainly spread through contact with the reproductive fluid of an infected dog.

This means that dogs can get it by mating with an infected animal or by coming into contact with infected semen, vaginal or menstrual secretions.

If an infected dog is pregnant, he can transmit the bacteria to his puppies in the womb, during birth or while drinking his milk.

Brucella canis infection is also possible via exposure to other infected biological material such as blood, feces, saliva, or snot, although this is considered less common.

How do people get Brucella canis?

People can contract Brucella canis through contact with fluids produced by infected dogs.

This usually happens when a dog gives birth, with veterinarians and dog breeders most at risk.

Infection occurs when material contaminated with Brucella canis comes into contact with people’s mucous membranes, such as the eyes and mouth, or through an open cut in the skin.

People can also get Brucella canis from other biological material produced by infected dogs, such as urine or feces, although this is much less likely.

However, repeated exposure over a long time increases the risk.

The bacteria can also spread through airborne droplets during very specific veterinary procedures involving an infected animal.

Human-to-human transmission of Brucella canis is technically possible through a transfusion of infected blood or an organ transplant, but no such cases have been recorded.

It is generally believed that people with compromised immune systems, such as cancer patients undergoing chemotherapy, are at greater risk of developing serious illness from a Brucella canis infection.

Officials have broken down where dogs have been recorded behind the 43 Brucella canis infections, with animals from Romania making the biggest contribution.  This data was measured by officials because 22 individual incidents may have involved multiple animals

Officials have broken down where dogs have been recorded behind the 43 Brucella canis infections, with animals from Romania making the biggest contribution. This data was measured by officials because 22 individual incidents may have involved multiple animals

What are the symptoms in dogs?

Symptoms can include general infertility in both male and female dogs, and miscarriage in the latter.

Other signs of an infection in both sexes include lethargy, loss of libido, premature aging and walking problems, usually due to back pain.

However, many dogs may not show obvious signs of a Brucella canis infection for years while still being contagious.

What are the symptoms in humans?

Brucella canis usually causes general flu-like symptoms in humans.

These include fever, headache, generally feeling unwell, aches and pains and unexplained weight loss.

Symptoms typically develop within three to four weeks after infection.

But as with dogs, some people who are infected may not show any signs for years.

This, combined with symptoms that can be common to many conditions, can lead to difficulties in diagnosing the disease.

People with Brucella canis may also suffer from recurring infections for several years.

Is there a test available?

Yes. Tests for Brucella Canis in both dogs and humans are available, although they are not 100 percent accurate.

The number of tests on dogs has skyrocketed in Britain, with 5,773 tests carried out between January and July this year, compared to just 1,332 in 2018.

How is it treated?

There is no cure for dogs. Euthanasia is the only recognized treatment if the dog is suffering from an infection.

Although antibiotics can be used to treat the infection, this dog can still transmit the infection to other animals and people.

Human cases are treated with antibiotics, although this has not always been successful.

Previous human cases also required surgical intervention if the infection became severe.

This graph shows the number of Brucella canis tests carried out in the UK each year

This graph shows the number of Brucella canis tests carried out in the UK each year

How can I reduce the risk of infection?

People who adopt an adult dog from a Brucella canis hotspot, such as Romania, will have to pay to have a Brucella canis test done, experts say.

If you adopt a puppy from Eastern Europe, checks should also be carried out when the dog is an adult, as there is an increased risk of a false negative result when the animal is still very young.

Brucella canis is technically incurable, meaning a dog with the disease will be a risk of infection for the rest of its life.

To reduce the risk of becoming infected yourself, an owner must take a number of precautions.

These include using personal protective equipment such as gloves and goggles when handling material contaminated by a dog’s urine, menstrual blood or birth fluids, and thoroughly cleaning the environment where the dog regularly lives.

It is recommended that infected dogs be neutered and given antibiotics to reduce the risk of transmitting the infection to other animals and people.

Both owners of infected dogs and the general public are advised not to allow dogs to lick their faces to reduce the risk of infection.

How can I protect my dog ​​from infection?

Preventing dogs from mixing with dogs that have Brucella canis is the best way to lower the risk of infection.

For example, keeping them on a leash in public areas can limit this contact.

However, official guidance states that a one-off ‘transient’ contact between animals on a single occasion is unlikely to lead to an infection.

But multiple or prolonged contact increases the risk.

If you already have a dog and want to adopt it from abroad, you are strongly advised to pay for a Brucella canis test, especially if the animal comes from hotspots such as Romania.

People with dogs infected with Brucella canis should inform holiday kennels of their pet’s infection before allowing their dog to stay there, in case it passes the bacteria on to other pets.

Is a Brucella canis infection dangerous?

The vast majority of Brucella canis infections in humans are mild.

No human deaths from Brucella canis have been reported worldwide.

However, serious diseases have been recorded, although rare.

Serious infections of the heart, bones, brain tissue and blood have been reported in people after Brucella canis infection.

Of the three cases discovered in people in Britain, one was later found in an immunocompromised person who required hospital treatment.

In the second case, a veterinarian employee took a test after contact with an infected dog. The results showed that they were positive, but they did not develop any symptoms.

No details have been shared for the third case.

The bacterial infection can jump to humans, although serious illness is rare.  Pictured the Brucella canis bacteria under a microscope

The bacterial infection can jump to humans, although serious illness is rare. Pictured the Brucella canis bacteria under a microscope

What is being done about the increase in cases?

In addition to the three human cases, there has been a sharp increase in the number of cases in dogs in Britain.

Human Animal Infections and Risk Surveillance (HAIRS), an intergovernmental group, recently published a report on Brucella canis in Britain.

This report details how 43 cases were found in dogs in Britain in the first quarter of 2023, more than double the comparable figure last year.

A further 48 cases were identified by the end of July, bringing the total this year to 91.

For comparison, a total of 143 dogs tested positive between 2020 and 2022.

HAIRS has said the rise in cases is likely linked to an increase in testing, partly due to increased awareness of the disease.

Although transmission of Brucella canis has been confirmed among British-born dogs, the majority of cases are still imported into Britain.

Dr. Christine Middlemiss, DEFRA’s Chief Veterinary Officer, has said the Government is considering introducing a mandatory testing requirement for dogs imported from Brucella canis hotspots.

“We are gathering the evidence, various risk assessments are adding to that evidence and we will consider it,” she said.