The North Carolina Department of Health and Human Services today released the final report on the public health investigation into an outbreak of Legionnaires’ disease in people who attended the NC Mountain State Fair held Sept. 6–15, 2019 at the Western North Carolina Agricultural Center in Fletcher, NC.
The investigation determined the outbreak of Legionnaires’ disease was likely caused by exposure to Legionella bacteria in aerosolized water from hot tubs on display during the fair. Hot tubs are a well-established source of aerosolized water exposure and have been linked to other Legionnaires’ disease outbreaks nationally and internationally.
The outbreak was first identified on Sept. 23, 2019, eight days after the Mountain State Fair ended. State and local public health departments rapidly launched an investigation with assistance from the U.S. Centers for Disease Control and Prevention (CDC) and in cooperation with the North Carolina Department of Agriculture and Consumer Services.
“This report highlights the rapid, coordinated public health response that occurred,” said Dr. Zack Moore, State Epidemiologist. “Thanks to the dedication and work of local and state public health staff and our partners, we were able to quickly rule out any significant ongoing exposures at the Western North Carolina Agricultural Center and provide early investigation findings to the public in less than two weeks.”
This outbreak is a reminder of the importance of caring for and properly maintaining hot tubs and other equipment that can aerosolize water. In response to this outbreak and investigation, the Division of Public Health and CDC have developed and distributed guidance for vendors and public health practitioners on how to minimize risks at fairs and other temporary events from hot tubs and other display equipment that aerosolizes water.
Legionnaires’ disease is a form of bacterial pneumonia (lung infection). People can get Legionnaires’ disease when they breathe in aerosolized water (small droplets of water in the air) that contains the Legionella bacteria. Legionnaires’ disease is a serious illness but can be treated effectively with antibiotics. Legionella bacteria can also cause a milder flu-like illness called Pontiac fever, which resolves without treatment.
The outbreak investigation identified 136 cases of Legionnaires’ disease and one case of Pontiac Fever in residents of multiple states and North Carolina counties who had attended the Mountain State Fair. Ninety-six patients were hospitalized and four died.
The final report and other information about the outbreak are available at https://epi.dph.ncdhhs.gov/cd/legionellosis/outbreak.html.
More information about Legionella bacteria and Legionnaires' disease can also be found on the CDC website at https://www.cdc.gov/legionella/index.html and on the DPH website at https://epi.dph.ncdhhs.gov/cd/diseases/legionellosis.html.