SAN FRANCISCO (CBS 5) – The San Francisco SPCA has warned Occupy SF protesters of a possibly fatal virus being spread among dogs who run free at the downtown encampment in Justin Herman Plaza.

Dr. Jennifer Scarlett, Co-President of the San Francisco SPCA, said three puppies were being treated at SPCA’s veterinary hospital for parvovirus. The virus discovery was made during a free vaccine clinic offered Monday.

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Each is 3 to 4 months old: “Hope,” a Shepherd mix; “Willarou,” a border collie; and “Lucille,” a Labrador mix are all very sick and hooked up to IVs for rehydration and medicine, Scarlett said.

Parvovirus is highly contagious and spread by dogs’ fecal matter. It causes vomiting and diarrhea and can be deadly, especially for puppies.

KCBS’ Margie Shafer Reports:

Scarlett said the virus can live in the soil for months. “So we have a population that is under a great deal of stress, living outdoors. Loud, unvaccinated, nutritional status questionable, that are just sitting ducks, you might say, for this disease.”

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SPCA officials believe there are many more dogs who have contracted the virus but their owners may not have taken advantage of the free clinic Monday because of a distrust among the campers of dealing with authorities.

“We have 3 confirmed, and how many did we miss? How many didn’t show up at our vaccine clinic?” said Scarlett. “How many just caught the disease yesterday – and will be clinical tomorrow? That’s what really keeps me up at night worrying about the animals down there.”

There were also dogs at the camp that showed symptoms of two other diseases: kennel cough and giardia, said SF SPCA spokesperson Krista Maloney.

The parvovirus can be contained with antiviral vaccines and humans are not threatened by any exposure – but giardia, another contagious disease that causes diarrhea, can be passed to humans said Maloney.

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