The Mahoneys say, Buddy, their 6-year-old German Shepherd, started having trouble breathing in mid-April.
On Easter, Robert Mahoney got the call confirming that he had tested positive for the virus.
He had been dealing with symptoms for weeks and during that time Buddy developed thick mucus in his nose and started breathing heavily.
The family says so little was known about the virus in animals and so much of the response was focused on saving human lives that it was difficult getting Buddy tested.
As they searched for a veterinarian that would test him for COVID-19, Buddy's condition continued to deteriorate.
They say he lost weight and became lethargic.
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Buddy was put on antibiotics, and later, steroids after other testing detected a heart murmur.
It took the family a month, but Bay Street Animal Hospital finally agreed to administer Buddy a test, which came back positive.
The family's other dog, a 10-month-old German Shepherd named Duke, was also tested.
His results came back negative.
Additional testing just five days later showed the virus was no longer in Buddy's system, though he did have the antibodies, confirming he had had the virus.
Even after his diagnosis, though, Buddy continued to get worse.
The Mahoneys say about every two weeks a new problem would arise; he could no longer control his bladder and his urine was bloody, his breathing grew much heavier, and then he developed trouble walking.
On the morning of July 11, Allison Mahoney found Buddy in the kitchen throwing up clotted blood.
"It looked like it was his insides coming out. He had it all over. It was coming from his nose and mouth. We knew there was nothing that could be done for him from there. What are you going to do for a dog with this? But he had the will to live. He didn't want to go," Allison told National Geographic.
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She and her husband rushed Buddy to the vet, and they made the decision to euthanize him.
New blood work the day Buddy was euthanized showed he most likely had lymphoma, a type of cancer.
The family says the most confusing part of it all was the fact that no one seemed interested in learning from Buddy's death or studying what role COVID-19 played in it, considering how few cases had been confirmed in animals.
National Geographic also points out that Buddy's death highlights the fact that the reporting of animal testing is not mandatory and is not widely shared, therefore there currently isn't enough data to know if, say like humans, animals with pre-existing conditions are more likely to contract the virus.
The Mahoneys say they're confident the team at Bay Street did their best for Buddy.
"I think they are learning as well. It's all trial and error. And they tried to help us the best way they can," Allison told National Geographic.
The Mahoneys chose to have Buddy cremated and they hope to pick up his ashes this week.
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