TUCSON (KGUN9-TV) - It's highly contagious and has no known cure.
"It's fatal in almost every instance," said Pat Brayer, clinic director at the Humane Society of Southern Arizona.
She's talking about distemper, a disease that affects dogs' respiratory and nervous systems.
The shelter has recently seen an increase in dogs entering the shelter with the virus.
Because of the outbreak, the shelter is not accepting new dogs for one week. They ask that anyone who wants to surrender a dog take it to Pima Animal Care Center.
"I think approximately five came to the shelter that were already infected but that is definitely a higher percentage than we would normally see," said Brayer.
She says the shelter had to euthanize several infected dogs whose symptoms were too far advanced. The shelter couldn't immediately provide 9OYS with exactly how many dogs had to be put down.
Brayer says puppies are the most vulnerable to this virus but there's no risk to fully vaccinated dogs.
"It's completely preventable," she said. "We encourage every dog owner to make sure their pet is fully vaccinated."
Symptoms of the virus include lethargy, dizziness and vomiting or diarrhea. Anyone who sees these symptoms in their pet should take them to the veterinarian immediately.
The shelter is offering free vaccination clinics during June and July to prevent the disease from spreading further.
Clinics will be offered every Wednesday, Friday and Saturday starting at 9 a.m. The shelter asks that you arrive promptly at 9 a.m. because they can only vaccinate approximately 35 pets at each clinic.
Brayer says the dogs still at the shelter are all healthy and available for adoption, but because of this outbreak, anyone who wants to surrender their pet now has to make an appointment to ensure the pet is vaccinated before it enters the shelter.
"The fact that we've seen the number that we have is definitely cause for alarm," said Brayer. "We know it's in the community."