The import of companion animals like dogs and cats, as well as people taking their pets abroad with them on holiday, poses a risk that they could be carrying an emerging infectious disease into the UK. There are currently concerns around Brucella canis infection, brown dog tick (Rhipicephalus sanguineus), the tapeworm Echinococcus multilocularis and heartworm Dirofilaria immitis (Wall, 2023) – all of which have varying effects on pets.
While animals are mainly affected, there are concerns around the risk some of these diseases may play to humans, and those working in veterinary practice may be particularly at risk.
Last month, when commenting on the King's speech which banned the live export of animals for slaughter, British Veterinary Association President Anna Judson said: ‘… the government needs to urgently turn its attention to strengthening rules on animal importation which are exposing the UK to the serious emerging diseases like B. canis.’
Brucella canis as a risk to humans
Since 2020, there has been an increasing number of reports of B. canis infection in dogs. Most of these have been in dogs directly imported into the UK from Eastern Europe, or in close contacts of these dogs.
In recent months, concern has grown around the spread of B. canis to humans. As of July 2023, two laboratory-confirmed cases of B. canis human infection have been found in the UK.
One of these cases was identified based on clinical suspicion in hospital. However, a second case had no clinical symptoms, worked at a veterinary practice and was identified through the follow-up of people exposed to B. canis-positive dogs by public health officials. In both cases, the dogs were not known to be infected at the time of human exposure, but subsequently tested positive for B. canis (UK Health Security Agency, 2023).
While the impact to human health has been assessed to be very low for the UK population, those working in veterinary settings are at higher risk – although it is still assessed as low risk, and immunocompromised individuals may be at higher risk of severe infection (UK Health Security Agency, 2023).
B. canis in the UK is still mainly associated with imported dogs and their canine contacts and/or offspring. Due to a lack of data, it is not currently possible to determine if it has become endemic in the UK dog population.
What veterinary professionals need to know about Brucella canis
The UK Health Security Agency (2023) recommends that those with a greater risk of exposure to B. canis, such as veterinary professionals and those in contact with potentially infected dogs, and/or susceptibility to infection (for example immunocompromised individuals who are at risk of exposure) should be informed of the risks and health impacts, as well as how dogs can be diagnosed within the UK. UKHSA also highlight that it is important veterinary professionals are aware that the risk of B. canis infection in dogs is higher in those coming from known endemic countries.
If caring for an imported dog with clinical signs suggestive of a possible B. canis infection in a veterinary setting, appropriate personal protective equipment should be used and testing should be arranged (Animal and Plant Health Agency, 2023). Table 1 shows the signs and symptoms of B. canis in dogs.
Table 1.
Signs and symptoms of Brucella canis (Animal and Plant Health Agency, 2023)
| Female dogs |
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| Male dogs |
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| Non-specific symptoms for both sexes |
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Parasitic risks
As mentioned previously, pets travelling abroad can be exposed to many different parasites. The tapeworm E. multilocularis is endemic in much of mainland Europe, with a few exceptions including the UK. Dogs returning to the UK must be treated for tapeworm before being allowed entry (Gov.uk, 2023a), and it is hoped these measures will stop it becoming endemic. E. multilocularis can also infect foxes, and if the parasite spreads into the large fox population there are fears it will quickly become endemic.
E. multilocularis can cause severe illness in humans, but dogs do not usually show clinical signs of infection. E. multilocularis is a notifiable animal disease (Department for Environment, Food and Rural Affairs and Animal and Plant Health Agency, 2021).
The heartworm D. immitis is another risk to travelling dogs. It is found in southern Europe, where it is spread by the bite of a mosquito. The disease can be prevented with use of an appropriate anti-parasitic medication. D. immitis does not affect people, but it can be serious in dogs.
Conclusions
While the risks of veterinary nurses – and the general public – contracting one of these diseases is low, it is important to stay up to date with the relevant advice in order to remain safe.