Air coli: New outbreak goes beyond food

The Hook's November 13 cover story highlighted the growing concern over a vicious strain of E. coli bacteria that has killed a child and seriously injured dozens more through the once unsuspected medium of sweet cider. Now comes word that the deadly bacteria can be transmitted through the air. –editor

At least 19 people who had gone to a county fair in Ohio in 2001 fell ill with E. coli after the bacteria apparently spread through sawdust in the air at an exhibition hall– the first time researchers have connected an outbreak to a contaminated building.

Testing at the building in Lorain County found E. coli O157 in the rafters, the walls, and the sawdust– in some cases 10 months after the fair.

"This is an entirely new mode of transmission," says Dr. Michael S. Donnenberg, professor of medicine and head of infectious diseases at the University of Maryland, who was not involved in the study.

The study was conducted by the Centers for Disease Control and Prevention and published in the November 26 edition of the Journal of the American Medical Association.

Tainted food is the most common source of E. coli outbreaks, which cause an average of 61 deaths and 73,000 illnesses a year in the United States. But people can also become infected from animal or human feces.

Altogether, 23 people who had attended the fair became sick with E. coli. Nineteen of them had gone to a dance at the hall or had otherwise visited the building, which contained exhibits involving cattle, sheep, horses, and dogs. The building had a clay floor covered with sawdust, and some of those at the dance complained the air was dusty.

E. coli can cause fever, abdominal cramps, and severe, sometimes bloody, diarrhea. While six of the infected were hospitalized, none died.

Hand washing is usually the best defense against E. coli, but it might not have worked in this case.

"We do not have any proof that persons were infected because the E. coli O157 landed directly in their mouth, but our study suggests this is possible," says Dr. Jay K. Varma of the CDC, who led the study.

Researchers were also surprised at how long E. coli remained in the building.

"It's possible that the E. coli that live for that long are not abundant enough or virulent enough to cause infection," Varma says, but the study "raises this as a dangerous possibility."

Researchers said the few precautions available for reducing the risk of outbreaks at fairs include not using sawdust, providing soap and water, and disallowing eating at places were animals are on display.

Since the study, the CDC has learned of two other outbreaks that might have been caused by building contamination, Varma says. One happened at the University of Wisconsin, the other at the Lane County Fair in Oregon.

Kimberly Kessel takes her 4-year-old son Makyah Outman for a walk with husband Tim Outman and younger son Kyler, 2, at their home in rural McKenzie Bridge, Oregon in June. The family has joined two dozen others in a lawsuit against the Lane County Fair Board.