We asked veterinarians and experts around town about the flu, and what you can do to prevent it.

How worried should I be?

“We should be concerned, but not panicked,” said Dr. Dennis J. Slade, an internist at the Animal Medical Center on the Upper East Side. Dr. Slade said that the current strain of the virus was pretty infectious and that it would most likely spread to other boroughs. While most healthy dogs should be fine, he said, there is about a 10 percent chance that dogs could develop a secondary infection that could be fatal.

What happens when a dog is infected?

Symptoms include cough, mild lethargy, a drop in appetite, possibly a fever and discharge from the nose and eyes, said Dr. John de Jong, the president-elect of the American Veterinary Medical Association. Dogs can infect others for weeks after symptoms have diminished.

What should I do if my dog becomes ill?

Call your vet. Sick dogs should be given fluids, rest and a proper diet, Dr. de Jong said. As a precaution, if your dog is infected or ill, keep it away from other dogs for at least three weeks.

Where did this flu come from?

This flu strain was first diagnosed in Asia around 2005 and it moved to the United States in 2015, when an outbreak in Chicago sickened thousands of dogs, said Edward Dubovi, a professor of virology at Cornell University College of Veterinary Medicine, which tracks the disease. Dr. Dubovi theorized that this strain came from dogs rescued from meat markets in South Korea.