The Fairfax County Animal Shelter has temporarily suspended its intake of new dogs after about a dozen canines exhibited symptoms of an unspecified upper respiratory illness and one died of pneumonia, officials said.

The staff said the infection could be Canine Influenza, which can spread rapidly through a shelter population and be transferred to cats. It does not pose a risk to humans, but people can transfer the virus to pets via their hands and clothes.

The staff is working with veterinarians on a treatment program and containment plan. The shelter will have test results confirming the cause of the outbreak by Tuesday or Wednesday.

Shelter volunteers and the public will be asked to take special precautions to prevent the spread of the illness. Sick dogs are being isolated from other dogs and the public while they undergo treatment.

The shelter will continue to adopt out healthy dogs.