The exotic tick-borne parasite, babesia gibsoni, has now been found in two dogs in Christchurch.
The Ministry for Primary Industries announced last week a staffordshire bull terrier had to be put down due to the parasite.
"It was found in a dog in Christchurch at the end of March 2024 and investigations revealed a second affected dog on 10 April," an MPI spokesperson said.
"We're working to find out how the two dogs became infected with this parasite not previously found in New Zealand and determine if there are other cases.
"Dog owners should ensure their animals' flea and tick treatments are up-to-date. Vets should contact us if they come across any suspected cases: freephone 0800 80 99 66."
Babesia gibsoni is a parasite that primarily only affects dogs and can cause anaemia, lethargy and other symptoms.
A small number of dogs that were close contacts of the initially infected animal were tested as part of the MPI's investigation.
Chief veterinary officer Dr Mary van Andel told 1News that led to the new infection being detected.
"This new case is a dog known to have been involved in a tussle with the first dog confirmed with the disease," she told 1News.
"This newly discovered dog has shown no obvious signs of illness."
The blood parasite was widespread overseas but it was still unclear how it came to be in New Zealand.
It most commonly affected bull breeds and greyhounds and was usually spread via ticks or dog bites.
Most dogs with the disease would only experience mild symptoms, but it could be severe in some cases, MPI says.
How is it spread?
Babesia gibsoni is blood-borne and spreads where there is transfer of blood between dogs. It can be transmitted by ticks and the New Zealand cattle tick (Haemaphysalis longicornis) is capable of spreading it between dogs. Ticks that are exotic to New Zealand, such as the brown dog tick (Rhipicephalus sanguineus) also spread this parasite.
Along with ticks, Babesia gibsoni can also be spread through dog bites, blood transfusion, and through the placenta from an infected mother to her pups.
In countries where Babesia gibsoni is widespread, the focus is on preventing infection by treating dogs with tick treatments (similar to flea treatments) and limiting fighting behaviour.
There are several approaches to treatment, however, these don’t completely eliminate the parasite which means dogs may remain carriers once infected.
What should dog owners do?
Dog owners should not be concerned. Most dogs with this disease will only experience mild symptoms, if any, and there are treatments to manage it.
It is important dog owners ensure their animals' flea and tick treatments are up-to-date. A range of tick treatments or combined flea and tick products are available over the counter in New Zealand. Owners should ask their vets about the best product for their particular circumstances.
Babesia gibsoni can also be spread through dog bites, so we recommend limiting any fighting between dogs. If you have any concerns about your dog’s health, talk to your veterinarian.
What is Biosecurity New Zealand doing about the parasite?
The investigation is focused on how the dogs in Canterbury became infected and understanding if there are any other cases in the country.
The second case was discovered through tests on all close contacts of the original case. All other dogs have so far tested negative, including a dog from the same household as the first case.
MPI does know that the second positive dog was imported to New Zealand two years ago. It met all importing requirements including tests for babesia gibsoni which were negative.
This dog’s owners have been issued with legal directions to manage any risk of spread.
We are asking vets and anyone else who works with dogs to help our investigation. Contact us if you have any suspected cases of babesia gibsoni – freephone 0800 80 99 66.
What species are affected by B. gibsoni?
Dogs are the most affected species. Pit bull terriers, Staffordshire bull terriers, and greyhounds are the most commonly affected breeds.
