DENVER - A few weeks ago, 9NEWS reported on an increase in dogs contracting the parvo virus. A virus that's easily preventable but once a dog has it, it can be very expensive to treat. The survival rate is about 50-50.

9NEWS put in a call to several shelters around the metro area, all of them are still seeing a steady influx of parvo virus.

The MaxFund Shelter in Denver had 15 puppies infected with parvo left on their doorstep.

"Fifteen just within the last month or so," said Heidi Hahn, Clinic Director at the MaxFund Shelter.

In some cases, the owners also leave a note saying they can't afford the treatment, and they know the puppies need medical attention immediately.

"It's incredibly frustrating, and it's heart breaking," Hahn said. "You see a box of four sick puppies, or you see puppy left in kennel with a note on it. Yes, this is the right place because we are a no-kill shelter. So, we're going to do what we can for the animal."

The vaccine for parvo is a series of three shots that average only $17.

"It's preventable," Hahn said. "It's a shot at 8, 12, and 16 weeks and they're time sensitive."

But compare that to the amount it costs to treat parvo.

"It's anywhere from $1,500 to $2,000, depending on the case," she said. "Parvo needs supportive care."

For more information on parvo go to: MaxFund Animal Wellness Center www.maxfundclinic.org or 303 595-0532

Planned Pethood Plus can provide affordable parvo treatment: 303-433-3291.

Spay Today can provide reduced rates on vaccines: 303 984 7729, as does Pet Aid Animal Hospital (formerly Harrison Memorial Animal Hospital): 303-772-5800

Kittens can also contract a form of parvo. Not many kittens get sick with the virus, because they don't often go out to parks and public places.