Skip all navigation Skip to page navigation

DHHS Home | A-Z Site Map | Divisions | About Us | Contacts

NC Department of Health and Human Services
NC Division of Public Health
N.C. Public Health Home


Investigation of an Outbreak of Legionellosis in Western North Carolina

Outbreak Summary

  • On September 23, 2019, the NC Division of Public Health was notified about an increase in the number of Legionnaire’s disease cases in Buncombe and Henderson counties.
  • 136 cases of Legionnaires’ disease or Pontiac Fever were identified in residents of multiple states and North Carolina counties who attended the NC Mountain State Fair, held September 6-15, 2019 at the Western North Carolina Agricultural Center in Fletcher, NC.
  • The Division of Public health has released a Final Outbreak Report (PDF) with findings from the investigation.
  • If you have questions about Legionnaires’ disease or the outbreak, you can find more information in our FAQ (PDF).
  • Final case count:
County of Residence Confirmed Cases*
Buncombe County 49
Burke County 1
Caswell County 1
Cherokee County 1
Gaston County 1
Granville County 1
Haywood County 11
Henderson County 33
Jackson County 3
Madison County 6
McDowell County 5
Mecklenburg County 5
Mitchell County 2
Polk County 1
Rutherford County 1
Transylvania County 3
Yancey County 1
Out of State 11

*No new cases linked to the outbreak have been identified since the end of October. Some previously reported cases did not meet the case definition for this outbreak once a full clinical and risk history were assessed.

Case Characteristics  
Male 77 (57%)*
Female 58 (43%)*
Median age in years (range) 61 (24-91)
Hospitalizations 96 (71%)*
Deaths 4
Legionnaires' Disease 135 (99%)
Pontiac Fever 1 (1%)

*some cases were reported with unknown gender or hospitalization status


Outbreak Case Definition

Clinical Criteria

  • A. Legionnaire’s Disease
    Pneumonia (clinical or radiologically confirmed) in an individual who attended or worked at the 2019 NC Mountain State Fair, with symptom onset within 2 – 14 days after fair attendance


  • B. Pontiac Fever
    Fever, myalgia, headache, chills, nausea, vomiting or diarrhea within 3 days of attending or working at the 2019 NC Mountain State Fair.

Laboratory Criteria

Laboratory confirmed Legionella

  • By culture: isolation of any Legionella organism from respiratory secretions, lung tissue, pleural fluid, or other normally sterile site
  • By detection of Legionella pneumophila serogroup 1 antigen in urine using validated reagents
  • By seroconversion: fourfold or greater rise in specific serum antibody titer to L. pneumophila serogroup 1 using validated reagents on specimens collected 3–6 weeks apart

Confirmed Case: Patient meets clinical criteria A or B AND laboratory criteria

Sources and for more information: