Cases of parvo are especially bad this spring, with Arizona being one of the states hit the hardest.
Animal experts say parvo can kill your dog within three days of exposure.
According to animal rescue worker Cheryl Wade, Parvo is always a worry. However, what's different this year is the amount of cases popping up so quickly.
"We're scared. I'm scared. I'm on the streets 12 plus hours a day (looking for sick animals)," Wade said.
Wade blames a mild winter for the increase in cases. That is because parvo normally dies off in freezing temperatures. This winter, though, it barely happened.
To keep your dog safe, experts strongly recommend that you make sure they are up-to-date on vaccinations.
Even with medical care, parvo has a less than 50% survival rate.
As for the warning signs, most dogs get unusually tired when they first get parvo.
From there, they will likely have major stomach issues and start losing weight rapidly.