J Bacteriol Virol.  2002 Dec;32(4):299-306.

Seroprevalence to Coxiella burnetii in Patients with Acute Febrile Episodes during 1993

• Jung KD
• Jang WJ
• Kim JH
• Lee SH
• Kim IS
• Choi MS
• Kim YW
• Hwang YI
• Park KH

Abstract

Coxiella burnetii is the etiological agent of Q fever, that may occur either acutely or the chronically. To understand the seroepidemiological patterns of C. burnetii infection in Korea, we examined a total of 3,178 sera from patients with acute febrile episodes by using indirect immunofluorescence assay (IFA) for detectable antibodies to C. burnetii and other eight rickettsial antigens. The IFA seropositivity>or=1:20 for C. burnetii phase II was 11.5% (368 out of 3,178 sera). The co-existence of antibodies to other rickettsial antigens was found in 216 out of the 368 positive sera. Thirty-seven point five percent (n=138) had antibodies to R. tsutsugamushi (cutoff>or=1:20), 16% (n=59) to Ehrlichia sennetsu, 14.9% (n=55) to Rickettsia typhi, 13.5% (n=50) to R. akari, 11.4% (n=42) to R. japonica, 8.9% (n=33) to R. prowazekii, 7.6% (n=28) to R. sibirica, and 6.7% (n=25) to R. conorii by IFA, respectively. These results are consistent with previous reports documenting diverse serum cross-reactivity in chronic Q fever. Therefore we excluded the samples that reacted to other rickettsial antigens at same or higher titers than to C. burnetii, resulting in the seropositive rate of 4.1%. The serological prevalence was 2% (n=64) when the conventional cut-off titer of 1:80 was used. Our results suggest that infections with C. burnetii are more prevalent than expected previously and should be differentially diagnosised for febrile illness occurring after exposure to ticks or other vectors.

Keyword

C. burnetii; Q fever; Rickettsia; Sero-epidemiological survey; Korea

MeSH Terms

Antibodies
Coxiella burnetii*
Coxiella*
Diagnosis
Fluorescent Antibody Technique, Indirect
Humans
Korea
Neorickettsia sennetsu
Prevalence
Q Fever
Rickettsia
Rickettsia typhi
Seroepidemiologic Studies*
Ticks
Antibodies