A dog from North Carolina who died of “acute illness” earlier this month has positive for coronavirus, authorities said on Monday.

Death may be a rare, potentially fatal case of COVID 19 in a pet, but it is still unknown if there are other factors that have led to its death.

After signs of respiratory distress earlier that day the dog was taken to NC State Veterinary Hospital in Raleigh, the Department of Health and Human Services of North Carolina said in a statement.

The person taking the animal to the hospital told his staff that a family member had tested positive for coronavirus previously, but a subsequent test showed negative results, the department said.

The department received no further detail on the dog or person who brought him to the hospital citing patient confidentiality.

The dog died the same day, a spokeswoman for the department said. A positive outcome was obtained from the dog examined in a medical lab, which is verified by the United States. National Veterinary Services Laboratory Department of Agriculture, the statement said.

Investigators also sought to figure out why she died, the statement said.

According to a registry compiled by the Department of Agriculture, only a few animals have developed the disease in the United States. The Centers for Disease Control and Prevention found that most of these infections have occurred after contact with people who have coronavirus.

The Department says there is still a small risk of animals transmitting the disease to humans.

As of Aug. 7, when the list of dogs was last updated, 13 cases of dogs in 8 states were confirmed, including a previous positive antibody test in North Carolina. Many cats, according to the report, have contracted the disease. Eight lions and tigers in the Bronx Zoo did likewise.

National Geographic announced last month that the first dog to test positive in the USA, the seven-year – old German shepherd named Buddy from New York, died six weeks after the disease was identified.

The magazine mentioned Buddy having lymphoma at his death, and how much the cancer and the virus have led to his death is unknown.

Michael San Filippo, a US Veterinary Medical Association spokesperson, says most dogs contracting the disease are asymptomatic or display only mild symptoms of infection.

This “seems to indicate this dogs don’t have a big problem,” he said. “So we have to know more about how it could interact with other disorders in order to create more serious problems. We ‘re also vigilant to keep pets away from the sick and to maintain a social distance between your pet and other pets and those away from home.”