Brucellosis is a hot topic in the UK veterinary world currently. This bacterial disease can have serious consequences for both pets and people, and vets are on the front-line for diagnosis, prevention, management and control. Many veterinary surgeries and hospitals are putting certain controls in place to try and reduce risk to both staff, clients and patients – but are they right to do so?
Table of contents
What is brucellosis?
Brucellosis is a highly infectious disease, caused by the bacterium Brucella canis. It can affect dogs of all breeds, sizes and ages, although is most common in breeding dogs. It can also spread to humans and cause severe disease, especially in the young, elderly and immunocompromised.
The risk to animal heath
Infection with Brucella canis can cause a range of symptoms in dogs. Many infected animals show no signs of illness, but can still transmit the disease. Others will become severely unwell. In pregnant female dogs, brucellosis can cause miscarriage or stillbirth of puppies, and affect fertility and uterine health. In male dogs, infection can result in infertility and testicular disease. But in all dogs, this bacterium can cause spinal pain, uveitis (swollen eyes), lethargy, swollen lymph nodes and kidney infections.
Brucella canis is spread between dogs mainly via bodily secretions, such as saliva, vaginal discharge, semen and urine. The bacterium can survive on surfaces in the home, and be transmitted through sniffing or licking at infected objects such as food and water bowls or bedding.
The risk to human health
B. canis is a zoonosis – this means it can be transmitted from dogs to people. Infection via this route is not hugely common, but the consequences can be severe. Infection is usually through contact with infected bodily fluids, such as aborted material, vaginal discharge or birthing fluids. This means that people around infected dogs at time of birth, such as dog breeders or vets, are more at risk. Brucellosis can be transmitted via the person’s mouth, eyes, broken skin or through droplets in the air. The bacterium can also be found in milk, faeces, urine and saliva, although in much lower numbers, and can survive in the environment on surfaces and objects.
Symptoms in humans are often fairly vague: fever, headache, back pain, fatigue and weight loss. If untreated, the disease can become chronic and more severe.
Treating brucellosis
Treatment for this disease is not easy. Antibiotics can control the infection, but there is no known cure or fully effective treatment. Neutering can also help control the risk of transmission, and manage the most common symptoms. However, current guidance from the Animal & Plant Health Agency (APHA) recommends euthanasia of infected dogs: to prevent suffering and to reduce transmission of disease.
Why should we be worried?
Brucellosis is currently an uncommon disease in the UK. It is mainly seen in countries with high populations of stray dogs, as it is usually spread through breeding. However, case numbers of B. canis are rising rapidly, correlating with the huge increase in imported dogs.
According to the APHA, more than 66,000 dogs were imported into the UK in 2020, and there are likely to be many more who entered illegally. Currently, imported dogs do not need to undergo any form of health testing, they merely need a rabies vaccination and some worming treatment.
Cases of brucellosis are rising rapidly in the UK. Before 2020, only three cases were recorded. Between 2020 and 2021 there were 87 recorded cases, and 54 in 2022. These numbers may well be the ‘tip of the iceberg’, as many infected dogs have no symptoms, and the disease has only recently become reportable.
Brucella canis is known to be highly infectious. It is very likely that cases will continue to rise – and quickly.
A recent case highlights the risk to both animals and humans. A dog foster carer took on a pregnant dog imported from Europe. She contracted brucellosis and was hospitalised for over two weeks. Three of her four dogs also became infected, and all dogs were euthanised. This was a tragic case, and many veterinary professionals are worried it will become a more common story if certain measures are not put into place.
Are changes being made?
The government is currently reviewing risk assessments for bacterial disease. Leading voices in the veterinary world, including renowned parasitologist Ian Wright, have called for stricter control on imported dogs, by making testing for diseases such as brucellosis compulsory.
Vets are obviously concerned with animal health and welfare, but they have a degree of responsibility for public health as well – and this includes them and their families. Dogs carrying Brucella canis are of risk to both staff, clients and patients when undergoing treatment at a veterinary surgery. This is why many vets are now imposing some new controls when dealing with dogs imported from abroad. This may include compulsory testing for brucellosis, barrier nursing to protect other patients and wearing protective equipment to protect staff. If you have a dog which has come from abroad, you may find vets unwilling to see your dog in non-emergency scenarios unless they have been tested for Brucella.
These measures are not an over-reaction, or a punishment for those who chose to import dogs from overseas, but a sensible precaution when dealing with a highly infectious and potentially serious infection. Brucellosis is currently uncommon in the UK, and we all want to keep it that way.
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Discussion
I would love to see the evidence that the author used when making this claim: “Brucella canis is known to be highly infectious.”
It is, though, from products of abortion and other reproductive fluids, which is what this is talking about: “B. canis is a zoonosis – this means it can be transmitted from dogs to people. Infection via this route is not hugely common, but the consequences can be severe. Infection is usually through contact with infected bodily fluids, such as aborted material, vaginal discharge or birthing fluids.”
Massive Knee Jerk over reaction.
Here was hardly any recordings of this before because they weren’t screening all foreign dogs before, now more and more vets demand the test and so of course this disease that causes no effects to many dogs and merely non lethal fly symptoms to humans in very rare occasion in countries endemic with it. Euthanasia such a mild disease, when the real issue is dog imports sre high because dog breeding in UK has become an expensive monopoly.
If the idea is to protect healthy dogs, why are we putting down healthy dogs to accomplish it.
But it’s not a mild disease, and the fatality rate in humans is reported as 4%.
I think we need to be exceptionally clear here that David Harris is NOT saying that there is a mortality rate of 4% among people infected with Brucella Canis. The government HAIRS report (2021) could find NO cases of human mortalities from Brucella canis. Therefore, we currently are working on a published mortality rate of 0% for Brucella canis. Mortality from some other species of Brucella is reported in humans, but I would be keen to see a reference for the 4% value.
Absolutely, Brucella canis is so massively underdiagnosed (given its biological differences from other clinically relevant Brucella species) that we don’t have the information to determine a mortality rate.
Irritatingly I can’t put my hands on the papers citing a 4% mortality rate in Brucellosis more generally, but I agree that in the UK it’s unlikely to be that high with rapid diagnosis and treatment… if, that is, patients and medical staff recognise it as a differential diagnosis. Many people insist that this is such a rare disease there’s no need to test, which isn’t the case…
But I still think we need to be very clear that there are currently NO scientific reports of anyone dying from Brucella canis. Indeed, the UK government HAIRS Report 2021 highlights this in their report. A key feature of this report is the extrapolation across of different claims simply because it has NOT been reported in the scientific literature as a consequence of Brucella canis. So, while it is always important to be watchfully aware with any disease with infectious component, we should be careful to keep this in proportion to the evidence available. At the moment, Brucella canis appears to have a 0% risk of mortality in humans.
That is true – but it is equally true that there were no scientific reports of anyone dying of Covid in January 2020. While no-one is arguing that B. canis is like Covid, deaths from exotic diseases are systematically underreported because no-one looks for them. Since B. canis is harder to diagnose using standard medical testing techniques than other Brucella species, it seems quite unlikely that it would be unique in being non-virulent to humans, when we know that serious complications have occurred and been caught and rapidly treated. How many others were not caught and were not reported as B. canis because no-one thought to look?
So if it is infectious disease and you care about health and wellbeing, why on earth you are requiring imported sogs who have been here for years to now have this test done and not testing any home bred dogs ? Surely imported dogs could pass on bacteria already or you know something differently?
Yes they could – but as far as we know the chances of a home-bred dog having the infection is much lower than an imported dog. Unfortunately, we have to play the probabilities – the condition has historically been so rare in UK bred dogs that the risks of false positives on testing are disproportionately high, even when using a modern twin-test protocol.
So as we now have a lot of imported dogs playing around with home bred dogs , chances are definitely going higher that home bred dogs are likely to be infected , but if we don’t test them we don’t know and numbers are going to be low right ?
It’s not transmitted THAT easily! I’d be more worried about imported dogs breeding with naive local dogs and spreading the infection that way. I do know that some practices will test every dog who had an imported parent for that reason; perhaps more should be…
So, in that case, perhaps we should consider instead routine neutering of imported dogs, and testing instead if they have clinical signs for are intended for breeding? By your own admission (you have been a star pupil in that respect and a considerable about face from the VV crowd over the last 4 months so well done), the risk of false positives is very high when prevalence is low. You are now acknowledging that it doesn’t spread THAT easily – so are the current draconian measures we are seeing within some practices really necessary? We are trained in infection control and risk management, care for other animals with zoonotic diseases routinely, and now by your own admission, the public health concern is not that great as it doesn’t spread ‘THAT easily’. Let’s take the next step towards sensible management and work with the rescue and owner community, rather than forcing clients into positions of euthanasing their family members unnecessarily.
I reviewed the data, with colleagues, and we drew our own conclusions – which is of course what we’re supposed to do.
I would have no problem with compulsory neutering of imported dogs, I think that’s a sensible solution if we’re stupid enough to keep importing them. B. canis is just one among many unpleasant exotic pathogens we really don’t need!
We have also written some newer articles on the subject, this one is Lizzie’s viewpoint, which isn’t necessarily identical to mine!
I have read your new articles. Indeed, many of my colleagues took time to contact me to let me that my work had clearly inspired an about face by Veterinary Voices, though somewhat shameful that one of the authors felt the need to quickly remove a late night post acknowledging my efforts in bringing this to mainstream veterinary. I think you may wish to review the 2.3% BC figure though by re-reading the paper that you took the figure from. Great to see you doing EBVM, but peer review might be helpful here.
Yes, good catch, thank you! 3 peer reviewers and I all missed that, probably because the paper alternated between B. canis and Br. canis… I’ve updated the article and the VVUK page has an update queued as well.
However, I don’t think it changes the balance of the points being made.
Well, vets practices , some of them , are now requiring all imported dogs to be tested otherwise they will not provide any further treatment until the dog is not tested and if dog test positive they offer euthanasia for the dog.
Some are; however, personally I think refusing treatment is an overreaction. Testing is really sensible – it’s a shame so few rescues test appropriately – because then we know what precautions to take.
Lots of rescues are testing and have been for ages. What I found very interesting is that their efforts have been badly dismissed in many veterinary quarters for using unreliable in house testing kits – but then I noticed that the Veterinary Voices document suggests using in house test kits as a way of getting round the issue of a high prevalence of false positive results among positive dogs when the prevalence of BC is low. Surely, as they propose using this test as a screening test and sending for external testing if the test is positive, they are proposing a solution which is similar or potentially worse than overseas dog rescues? They test and if positive, either do not send to the UK, or treat any comorbidities, then retest again at an external laboratory (commonly IDEXX Germany for the charities I most commonly liaise with), and only import the dog if it is now negative on this test? So, basically, the Veterinary Voices document, is now proposing a solution that rescues have been critiqued for over the last few years? Indeed, based on the FASTtest claimed figures for sensitivity and the APHA ones (and making the assumption – that may be erroneous – that any dog that is a true positive on the FASTtest will also be a true positive on the APHA one, the VV solution would thereby miss around 18 in every 100 positive dogs that the APHA tests would identify? Isn’t this one of the very concern that has led veterinary professionals to reject the in house tests from Rescues that have been leading the way in testing before importation?
Actually, I think the bigger concern with SNAP tests from overseas is the real issue with fraudulent documentation, that the Dogs Trust reported on a couple of years ago. I very much doubt that many in my, or your former, profession in the UK would falsify such data, and of course there are genuine rescues out there that are not fronts for puppy farming or worse. But inaccurate veterinary documentation from countries with a lower standard of professionalism in their veterinary sector is a very real issue.