If your new parrot looks droopy, be on guard. People who bought pet birds in the last three months may be at risk for an infection that can cause pneumonia, the Minnesota Department of Health said Friday.

The health department issued the alert after an employee of a Shakopee pet store, Petland, came down with the illness, known as psittacosis (sit-a-CO-sis), which can be spread to humans by infected birds.

State officials said that birds infected with the disease may have been sold at PetSmart stores throughout Minnesota since Oct. 1, as well as at the Shakopee Petland since its opening Nov. 10. Both stores have stopped selling the potentially infected parakeets, parrots, love birds and cockatiels.

The birds all came from a single Florida distributor.

The disease, once known as "parrot fever," can be treated with antibiotics, and has not turned up in any customers yet, said Dr. Joni Scheftel, the state public health veterinarian. But she said the health department is urging customers and employees alike to look out for its flu-like symptoms, such as fever, chills, headache, muscle aches, chest tightness and a dry cough.

"It can be very serious if it's not diagnosed and treated, but it's very easily treated with antibiotics," Scheftel said. "All we're trying to do is alert people to be aware."

She added that the illness is "absolutely not" connected to bird flu.

The Petland employee who fell ill has been treated and is now "doing fine," she said. The unidentified woman, who developed pneumonia, apparently was infected from contact with the dried droppings of a sick bird, Scheftel said. Petland officials could not be reached for comment.

Although healthy birds can carry the bacteria that cause the infection, it rarely spreads to people unless the bird itself is sick, Scheftel said. Sick birds may appear droopy and have diarrhea. The birds can be tested and treated by veterinarians, she said, and do not have to be returned or destroyed.

The health department learned of the Shakopee case only Friday, Scheftel said. The same day, Florida health officials notified Minnesota and other states that some infected birds had been shipped to pet stores in their areas. She declined to identify the Florida distributor involved in the case, saying only that it was taking the proper steps to correct the problem.

Jennifer Ericsson, a spokeswoman at PetSmart headquarters in Phoenix, said the company stopped selling the birds "a few days ago" after learning of the problem.

She said random tests found several infected birds at some PetSmart stores, though not in Minnesota. "We're sending a letter out to customers in those stores," she said, adding that there were no reports of illness among customers or employees. "We're doing this as a precautionary measure," she said.

PetSmart has also posted a fact sheet about the illness on its website, petsmartfacts.com.

Maura Lerner • 612-673-7384