Officials warn of swimmer’s itch

Friday, June 6, 1997 | 5:47 a.m.

Five people wading in Lake Mead have developed swimmer's itch caused by a flatworm larva. The ailment is not life-threatening, officials said.

National Park Service biologist Bill Burke said roughly one of three people who come in contact with the micrscopic parasites develop red spots about an hour after leaving the water. Then 10 to 15 hours later, the itching starts and lasts for about a week.

Three cases reported to the Clark County Health District came from Boxcar Cove, north of Las Vegas Bay. The other two developed at Rotary Cove, north of Callville Bay, and at Burro Point, northeast of Hoover Dam on the lake's Arizona shore.

The arrow-shaped fluke, called schistosome, needs ducks, snails and warm, shallow waters to flourish, Burke said. On-shore winds also help push colonies of them toward bathers and waders.

The parasite lives inside ducks and geese, then releases eggs into lake waters. The eggs hatch into small larvae that burrow into water snails. After incubating in the snails, the parasite moves back to waterfowl, maturing there.

Burke said the best thing to do is swim away from the shoreline to avoid pockets of the parasites. Also avoid sitting in shallow waters and keep moving at the shoreline, he said.