Giardia, a water-borne parasite, has people and pooches running for help again this summer, Utah Health Department officials and veterinarians say.

While campers may remember to bring their own water, or boil and treat water from campgrounds and streams, they often forget to protect their pets.And that is when the disease, affectionately known as the Rocky Mountain Two-Step, takes hold.

"There's quite a bit of giardia in pets," said Dr. Roger Kodel, a Salt Lake veterinarian, who estimates upward of 20 percent of dogs come down with symptoms associated with the disease. "We're seeing more cases than we used to see. I think there's more giardia around.

"We've seen a lot of dogs that have been in the watershed areas of the Uintas and Lake Powell" experiencing chronic diarrhea and dehydration caused by a canine strain of the parasite, said Kodel.

Giardia enters streams and lakes through animal wastes, and symptoms appear within three to 25 days after infection by the parasite.

Pets who are infected with giardia while romping through the swamps can infect their owners. Dogs can pick up the parasites found in contaminated water on their coats, said Ed Tierney, coordinator for the Utah Health Department's communicable-disease program.

When people do not wash their hands properly after petting their dogs, the parasite can get into food and water, Tierney said.

"We normally get 300-350 cases of giardia a year, and actually we're a little bit down at 89 through the end of June," Tierney said, adding it is during the summer months that those affected make trips to the doctor's office.

"People are out in the summer, exposed more, and they come down with it. A lot of people will go several months before they're diagnosed," he said.

People and dogs display similar symptoms, with diarrhea the most noticeable. Symptoms will reappear if giardia is not treated promptly and thoroughly.

"Giardia can be a problem that cycles, meaning you'll get sick, you'll wind up with diarrhea, it'll flush a large number of organisms out, and it will take three or four weeks for the ones that are left to build up enough numbers to cause symptoms again," Tierney said.

For humans and pets, lab tests of a stool sample can detect the organism and allow for proper treatment. For dogs, treatment is an antiflatulent, while people are given prescription drugs that destroy the organism.

Tierney also said over-the-counter medications that remedy the diarrhea cut down on acid production that may kill the organism, or prevent the body from trying to flush out the parasite.

"Giardia is one of the ones that won't go away without treatment," he said. While the very young and very old tend to seek medical help more frequently, "People in-between who wind up with diarrhea usually grin and bear it for a longer time."

The case for pets, however, is different, said Kodel.

"You wouldn't leave it untreated - it's such a profuse diarrhea. It would just get worse and worse."

Precautions for people include bringing water from home that is known to be contaminant free, boiling campground or stream water for at least 10 minutes and using iodine or chlorine tablets, Tierney said.

Kodel suggests leaving the pooch home during the outing or giving the pet antiflatulent treatments as a preventative measure if the family camping trip is near watersheds.