For the first time in the UK, three Britons have been infected with Brucella canis, a disease usually limited to dogs imported from Eastern Europe.
The unidentified cases contracted the bacterial infection after contact with infected pets, and at least one required hospital treatment for their symptoms.
But officials also revealed that the virus is spreading among UK canines for the first time, raising the possibility of more human infections.
In the first six months of this year alone, a record 91 cases were detected in dogs.
Here, MailOnline answers all your questions about bacterial infection, including how to protect yourself and your pet.
Brucella canis can infect both people and dogs but produces different symptoms
What is Brucella canis?
Brucella canis is a bacterial infection found primarily in dogs.
However, other canines, such as foxes, wolves, and coyotes, are also susceptible.
It was first identified in the 1960s, after breeders in the United States reported that their dogs were suffering miscarriages.
Brucella canis is considered an incurable disease in dogs and is also capable of infecting humans in rare cases.
While an infection is not a death sentence for animals, 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 Brucella canis cases in the UK come from imported dogs, mainly from Eastern Europe where the disease is most common.
However, health chiefs warned this week that the disease is spreading in the UK.
Is Brucella canis notifiable in the UK?
Yeah.
In 2021, Brucella canis became a notifiable animal pathogen across the UK.
This means that people are legally required to report a case to the Government’s Animal and Plant Health Agency.
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 transmitted primarily through contact with the reproductive fluid of an infected dog.
This means that canines can contract 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, she can transmit the bacteria to her puppies in the womb, during birth, or while they drink her milk.
Brucella canis infection is also possible through exposure to other infected biological material such as blood, feces, saliva or mucus, although it is considered less common.
How is Brucella canis contracted?
People can contract Brucella canis through contact with fluids produced by infected dogs.
This occurs most often when a dog gives birth, and veterinarians and dog breeders are most at risk.
Infection occurs when material infected 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 contract Brucella canis through other biological material produced by infected dogs, such as urine or feces, although this is much less likely.
However, repeated exposure over a long period of time increases the risk.
The bacteria can also spread through airborne droplets during very specific veterinary procedures with an infected animal.
Transmission of Brucella canis from person to person is technically possible through an infected blood transfusion or organ transplant, but no such cases have been recorded.
People with compromised immune systems, such as cancer patients receiving chemotherapy, are generally considered to be at higher risk of developing severe illness from Brucella canis infection.

Authorities have broken down where the dogs behind the 43 Brucella canis infections were recorded, with animals from Romania contributing the most. This data was measured by officials as 22 individual incidents that could involve several animals each.
What are the symptoms in dogs?
Symptoms can include general infertility in both male and female dogs and spontaneous abortion in the latter.
Other signs of infection in both sexes include lethargy, loss of libido, premature aging, and difficulty walking, most commonly due to back pain.
However, many dogs may not show obvious signs of Brucella canis infection for years while still being infectious.
What are the symptoms in people?
Brucella canis mainly produces general flu-like symptoms in people.
These include fever, headache, malaise, aches and pains, and unexplained weight loss.
Symptoms usually appear three to four weeks after infection.
However, like dogs, some infected people can go for years without showing any signs.
This, combined with symptoms that could belong to many conditions, can cause problems 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 are available in both dogs and people, although they are not 100 percent accurate.
Dog testing has soared in the UK with 5,773 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 suffers from its infection.
While antibiotics can be used to treat the infection, this dog can still spread the infection to other animals and people.
Human cases are treated with antibiotics, although this has not always been successful.
Previous cases in people have also required surgical procedures if the infection becomes severe.

This graph shows the number of Brucella canis tests carried out in the UK each year.
How can I reduce the risk of getting infected?
According to experts, people who adopt an adult dog from a Brucella canis hotspot, such as Romania, must pay to have a Brucella canis test performed.
If a puppy is adopted from Eastern Europe, checks should also be carried out when the dog reaches adulthood, as there is a greater risk of a false negative result when the animal is very young.
Brucella canis is technically incurable, meaning that a dog with the disease will be at risk of infection for the rest of its life.
To reduce the risk of becoming infected, the owner will need to follow several precautions.
These include using PPE, such as gloves and goggles, when dealing with material soiled by a dog’s urine, menstrual blood, or birth fluids, and thoroughly cleaning the environment where the dog lives regularly.
It is recommended that infected dogs be neutered and given antibiotics to reduce the risk of them 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 chances of contracting the infection.
How can I protect my dog from infections?
Preventing dogs from mixing with dogs that have Brucella canis is the best way to reduce the risk of infection.
For example, keeping them on a leash in public spaces can help limit such contact.
However, official guidelines state that a single “transient” contact between animals is unlikely to result in infection on a single occasion.
But multiple or sustained contact will increase the risk.
If you already have a dog and want to adopt it abroad, we strongly recommend that you pay for a Brucella canis test, especially if the animal comes from hot spots like Romania.
People with dogs infected with Brucella canis should inform boarding kennels of their pet’s infection before their dog stays there, in case they spread the bacteria to other pets.
Is a Brucella canis infection dangerous?
The vast majority of Brucella canis infections in people are mild.
No human deaths from Brucella canis have been reported worldwide.
However, serious, although rare, illnesses have been recorded.
Serious infections of the heart, bones, brain tissue, and blood have been reported in people after a Brucella canis infection.
Of the three cases detected in people in the UK, one was later found in an immunocompromised person who required hospitalization for treatment.
In the second case, a person who worked at a veterinarian was tested after contact with an infected dog. The results showed that they were positive but did not develop any symptoms.
No details have been shared for the third case.

Bacterial infection can affect people, although severe disease is rare. In the photo, the bacteria Brucella canis under a microscope.
What is being done in the face of the increase in cases?
In addition to the three human cases, there has been a sharp increase in cases detected in dogs in the UK.
Human Animal Infections and Risk Surveillance (HAIRS), an intergovernmental group, recently published a report on Brucella canis in the United Kingdom.
This report details how 43 cases were found in dogs in the UK in the first quarter of 2023, more than double the comparable figure from last year.
By the end of July, another 48 cases had been identified, bringing this year’s total to 91.
In comparison, a total of 143 dogs tested positive between 2020 and 2022.
HAIRS has said the increase in cases is likely related to an increase in testing due in part to increased awareness of the disease.
While transmission of Brucella canis between dogs born in the UK has been confirmed, the majority of cases are still imported into Britain.
Dr Christine Middlemiss, DEFRA’s veterinary director, has said the Government is considering introducing a mandatory testing requirement for dogs imported from Brucella canis hotspots.
“We are gathering evidence, various risk assessments are contributing to that evidence and we will consider it,” he said.