Even as officials at Harford Memorial Hospital sought to identify new cases of Legionnaire's disease, experts say outbreaks of the infection are far more common nationwide than many people believe and could be controlled.
"It's hundreds of other hospitals that this is happening to right now," said Dr. Victor Yu, the country's leading expert on Legionnaire's and a professor of medicine at the University of Pittsburgh. "There are ways to prevent Legionnaire's disease that any hospital in the U.S. should be doing."
Five cases of Legionnaire's disease have been diagnosed at Harford Memorial since June 26, and three people, 79-year-old Elizabeth M. Cox and two unidentified patients, have died. Preliminary tests show that the source of the infection is a hospital water tank.
Officials said yesterday that a staff of 10 nurses have contacted about 350 of the more than 400 people hospitalized at Harford Memorial since May 1, including a half-dozen who were identified as particularly vulnerable by a Johns Hopkins Hospital epidemiologist.
"We have been constantly on the lookout for new cases," said Bob Netherland, a spokesman for Upper Chesapeake Health Systems Inc., which runs the hospital. "We have not identified any new cases since Friday."
The Havre de Grace facility heat-treated and flushed its water system to kill any bacteria on July 2. The incubation period for the disease is two to 10 days.
The bacteria that causes Legionnaire's grows well in lukewarm water and is found everywhere from creeks to people's homes. A person can breathe the bacteria through aerosolized droplets from showers and air conditioners or inhale droplets while drinking water.
The elderly, heavy smokers and people with weakened immune systems are most susceptible to the disease, a form of pneumonia.
According to the U.S. Centers for Disease Control and Prevention in Atlanta, 20 percent to 60 percent of hospitals have Legionella bacteria in their drinking water. As a result, Yu and others have called for hospitals to test the water every year, as is being done in the Pittsburgh and New York City areas.
But the CDC says more research must be done before adopting that guideline for health care facilities nationwide.
"We just don't have the data to know," said Barry Fields, chief of the CDC's respiratory disease diagnostic lab.
No mandated testing
