Dogs imported into Finland may bring along new infectious diseases

June 19/2019

The number of dogs imported into Finland has increased in the recent years. The import of dogs from countries with a different disease situation than Finland can contribute to the spread of diseases also in Finland as well as their formation as a permanent problem. Some of the diseases can also be transmitted to humans with serious consequences, and this could entail great costs for society, for example, by cases of suspected diseases caused by illegal imports. The Finnish Food Authority’s Risk Assessment Unit has assessed whether the import of dogs into Finland poses a risk to humans or animals in Finland with regard to certain diseases.

The risk assessment focused especially on the rabies vaccine antibody levels of imported dogs and on whether the dog was carrying canine brucellosis (Brucella canis), the Echinococcus multilocularis parasite and antibiotic-resistant ESBL-producing bacteria and MRSA bacteria. In addition, the samples taken from dogs were analysed for presence of Dirofilaria repens, Dirofilaria immitis and Leishmania infantum (leishmaniosis). As part of the risk assessment, samples were taken from imported dogs for the purpose of conducting the analyses mentioned above.

Climate change can contribute to the emergence of new parasites

The parasite Echinococcus multilocularis does not occur in Finland, and the situation is maintained by, for example, requiring medication against tapeworms for all dogs imported into Finland. The parasite can also be transmitted to humans and cause serious illness. Dogs carrying the parasite don’t have symptoms.

Based on the conducted risk assessment, however, wide spreading of Echinococcus multilocularis in Finland is not likely, if the import requirements are followed. On the other hand, sporadic Echinococcus multilocularis exposures can occur, if dogs are imported illegally from endemic areas without treatment against echinococcosis.

Some of the studied parasitic diseases can also be spread by mosquitoes. Based on the risk assessment, the risk of an epidemic is minor for leishmaniosis and D. immitis, but in case of D. repens, a larger epidemic is possible, because the parasite can spread by mosquitoes already present in Finland. The climate may also change over the next few decades to favour the spread of leishmaniosis.

Bacteria and resistance to antibiotics can also spread through imports

MRSA bacteria and ESBL-producing bacteria are multidrug-resistant, i.e., they are capable of resisting several types of antimicrobial medication. Although they already occur in Finland, the resistance situation is good. Because dogs live in close contact with humans, resistant bacteria can easily be transmitted between them. 

The ESBL property has been identified, among others, in the bacterium Escherichia coli which is normally present in the intestinal flora of humans and animals without causing any illness. The main risk factors for ESBL carriage in dogs are feeding raw meat and use of antimicrobial medication. In imported dogs, ESBL appears to be quite common, whereas MRSA was not present in the dogs examined.

The risk of antimicrobial resistance in an imported dog depends, for example, by the hygiene level and the use of antibiotics in the country of origin. The health status and diet of the dog affect whether the dog will remain a carrier of resistant bacteria. The dog carrying resistant bacteria may be healthy and asymptomatic.

Dogs are imported into Finland from countries where Brucella canis infections occur. B. canis is mainly transmitted in connection with mating, as well as through aborted fetuses and obstetric secretions. As a result, imported dogs that are sterilized or castrated have a lower risk of spreading the disease than dogs imported, for example, into kennels for breeding purposes. The bacterium can rarely also be transmitted to humans, but its significance to public health is still unclear. 

Rabies must always be taken seriously

Finland is rabies-free, and all imported dogs must be vaccinated against it. In addition to dogs, rabies can be transmitted to humans and other mammals. Rabies is always lethal, if prophylactic treatment is not started in sufficient time after the exposure.

The risk of an imported dog being infected with rabies depends on the disease status of the country of origin, the vaccination status, and whether the dog has lived as a street dog, for example. On the basis of our risk assessment, there are at least 400 unvaccinated dogs arriving in Finland from rabies areas each year and, in addition, approximately 80 dogs with insufficient antibody levels due to other reasons.

Unvaccinated dogs imported from rabies areas pose a risk, even if the likelihood of an individual dog having rabies is low. A rabies-infected dog always poses a high risk to the people and animals in close contact with it. If the vaccination coverage of dogs in Finland is high, the spread of the disease in Finland is not likely.

Dogs are imported into Finland from several countries

Dogs are imported into Finland from several countries worldwide. Most dogs are imported from Russia, Spain, Estonia and Romania. Dogs imported into Finland can be roughly divided into registered dogs, which are imported, among other things, for breeding, and so-called rescue dogs and dogs from puppy mills. Adult dogs imported from Romania and Russia are usually street dogs, i.e., their background is at least partly unknown. They may also have been exposed to various illnesses even before arriving at the dog shelter.

Dogs imported from Spain are usually abandoned pets and hunting dogs that most likely have not been street dogs for a very long time. The background of these dogs is not fully known either. Homeless dogs are imported into Finland by both registered associations as well as private people.

The risk assessment carried out is based on information obtained from samples of imported dogs, published scientific research and expert interviews. See the report Zoonotic pathogens in imported dogs (in Finnish), the description in English.

Read
An imported dog may pose a risk
Those importing a dog or considering transferring a dog to Finland can review the current import regulations from the Finnish Food Authority’s website:
from EU countries 
outside of the EU 

For more information, please contact:
Heidi Rossow DVM (PhD), Senior Researcher, tel. +358 40 548 0071, Risk Assessment Unit
Suvi Joutsen LVM, Senior Researcher, tel. +358 50 500 4056, Risk Assessment Unit
Pirkko Tuominen DVM (PhD), Head of Unit, tel. +358 400 211 624, Risk Assessment Unit