The pet dog of a family taking part in a study at Duke University is apparently the first in the U.S. to test positive for the virus that causes COVID-19.

Dr. Chris Woods, the lead investigator of the Molecular and Epidemiological Study of Suspected Infection (MESSI), confirmed in a statement to CBS News that, "To our knowledge, this is the first instance in which the virus has been detected in a dog. Little additional information is known at this time as we work to learn more about the exposure."

Early last month, Hong Kong health authorities said a coronavirus patient's pet dog that tested positive for the virus was "likely" the first case of human-to-animal transmission. Since then there have been several cases reported in cats, but research shows dogs are not very susceptible to the virus.

Winston, the pug. McLean family

WRAL-TV in Raleigh, North Carolina, which was first to report the U.S. development, said the dog, a pug named Winston, is part of a family in Chapel Hill.

Get Breaking News Delivered to Your Inbox

The mother, father and son in that household were enrolled in the study and tested positive as well, WRAL said.

But another family dog and a cat didn't test positive. The family's lizard wasn't tested.

The station quoted the mom, Heather McLean, a pediatrician at Duke, as saying Winston was having mild symptoms.

Son Ben McLean told CBS News, "There may be more animals that have coronavirus, there just isn't any testing. Obviously those tests should be going to people rather than pets, but because we were part of a research study, we found out about Winston."

"However," he added, "people should not worry about their pets getting sick and dying from this disease, there remains little evidence that it is very harmful to them."

He told WRAL that Winston "licks all of our dinner plates and sleeps in my mom's bed, and we're the ones who put our faces into his face. So, it makes sense that he got" the virus.

According to WRAL, the McLeans' daughter, Sydney, was the only family member who didn't test positive. Her husband works in the emergency room at UNC Hospitals.