Cobb County’s animal shelter will remain closed after two dogs housed there tested positive for a highly contagious bacterial infection, county officials said Wednesday.

The shelter closed last week after a half-dozen pets became sick. Samples sent to the University of Georgia’s Veterinary School showed at least two dogs tested positive for streptococcus zooepidemicus, an infection that affects the respiratory system and spreads quickly among animals in close contact.

The infection is believed to be responsible for the death of at least one dog at the shelter in the past week, though additional animals housed there have died recently, county spokesman Ross Cavitt said. Several other dogs and cats are being treated for symptoms of “strep zoo."

Veterinarians believe an animal dropped off at the shelter likely spread the infection to others, though they probably won’t be able to pinpoint which pet was responsible for the outbreak. Cobb Animal Services said it has ordered antibiotics and will begin treating the animals when the medicine arrives Friday.

As of Wednesday, the shelter had 157 cats and 111 dogs.

Any animal showing symptoms will be quarantined, and all the dogs and cats housed at the facility must go two weeks without symptoms, Cavitt said.

“If an animal shows symptoms on Tuesday we’ll have to restart the clock,” he said.

This isn’t the first time Cobb’s shelter has dealt with an outbreak of the bacterial infection. Last fall, at least two dogs died of strep zoo, though the infection was likely responsible for the deaths of additional animals.

“Our Animal Services personnel dealt with a strep zoo outbreak a year ago,” Randy Crider, Cobb’s public safety director, said in a statement. “They quickly contained the outbreak then, and their experience will help them keep the infection from spreading this time. It is important for us to save the lives of the dogs and cats we are caring for.”

In the meantime, animal services officers will continue to respond to calls and any pet brought to the shelter will be kept separate from the other animals. The facility will undergo a deep cleaning and those who recently adopted pets will be notified of the outbreak and advised to seek treatment for their dog or cat, if necessary.

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