A large Q fever outbreak in an urban school in central Israel.
BACKGROUND. On 28 June 2005, numerous cases of febrile illness were reported among 322 students and employees of a boarding high school located in an urban area in central Israel. Subsequent investigation identified a large outbreak of Q fever which started 2 weeks earlier. We describe the investigation of this outbreak and its possible implications. METHODS. We conducted a case-control study to identify risk factors for Q fever disease. Environmental sampling was conducted to identify the source and the mode of transmission of Coxiella burnetii, the infectious agent. RESULTS. Of 303 individuals, 187 (62%) reported being ill between 15 June and 13 July 2005. Serological evidence for C. burnetii infection was evident in 144 (88%) of the 164 tested individuals. Being a student, dining regularly at the school dining room, and boarding at school during a June religious holiday and the preceding weekend were all significant risk factors for contracting Q fever. C. burnetii DNA was detected using polymerase chain reaction on samples from the school dining room's air conditioning system, supporting contribution of the air conditioning system to the aerosol transmission of the infectious agent. CONCLUSIONS. We report a large outbreak of Q fever in an urban school, possibly transmitted through an air conditioning system. A high level of suspicion for C. burnetii infection should be maintained when investigating point source outbreaks of influenza-like disease, especially outside the influenza season.
Amitai
Ziva
Z
Tel Aviv District Health Office, Ministry of Health, Israel.
Bromberg
Michal
M
Bernstein
Michael
M
Raveh
David
D
Keysary
Avi
A
David
Dan
D
Pitlik
Silvio
S
Swerdlow
David
D
Massung
Robert
R
Rzotkiewicz
Sabine
S
Halutz
Ora
O
Shohat
Tamy
T
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000389:Air Conditioning; D000907:Antibodies, Bacterial / Q000097:blood; D016022:Case-Control Studies; D016997:Coxiella burnetii / Q000302:isolation & purification*; D004269:DNA, Bacterial / Q000302:isolation & purification; D004196:Disease Outbreaks; D004783:Environmental Microbiology; D005260:Female; D006801:Humans; D007557:Israel / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011778:Q Fever / Q000453:epidemiology*; D012574:Schools; D014505:Urban Population; D055815:Young Adult
D000907:Antibodies, Bacterial; D004269:DNA, Bacterial