PHOENIX — At least 50 dogs in the Phoenix area have been sickened by a bacterial infection since last year that can be spread to people, a health official said.

Craig Levy with the Maricopa County Department of Health said such a large number of leptospirosis cases in a year is rare.

“We’ve got 50-plus dogs reported so far. In an average year, the entire state of Arizona might see about five cases,” he said, adding that three dogs have been killed by the infection since February 2016.

Levy said the majority of the cases have been reported in Scottsdale, but others have been reported in Phoenix, Gilbert, Tempe, Litchfield Park and Avondale.

Dogs infected with leptospirosis — also called Weil’s disease — can display several different symptoms, according to Levy.

“A lack of energy, a lack of appetite, excessive urination and excessive thirst or, sometimes, just not urinating at all,” he said.

Levy said the infection is spread through urine, be it from dogs or another animal.

He said dog owners who think their dog may be infected should wear protective clothing when cleaning up after their animal, avoid dog parks and daycares and should get the dog to the veterinarian for treatment.

“Getting the leptospirosis vaccine and the appropriate vaccine for your pet is probably a pretty good idea,” he said.

The cause of the recent outbreak is unknown.

“A traveler bringing an infected dog from outside the state could have been the introduction source for the infection, but we don’t know that,” Levy said.

KTAR’s Bob McClay contributed to this report.

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