%0 Journal Article
%T Detection of Q Fever Specific Antibodies Using Recombinant Antigen in ELISA with Peroxidase Based Signal Amplification
%A Hua-Wei Chen
%A Zhiwen Zhang
%A Erin Glennon
%A Wei-Mei Ching
%J International Journal of Bacteriology
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/707463
%X Currently, the accepted method for Q fever serodiagnosis is indirect immunofluorescent antibody assay (IFA) using the whole cell antigen. In this study, we prepared the recombinant antigen of the 27-kDa outer membrane protein (Com1) which has been shown to be recognized by Q fever patient sera. The performance of recombinant Com1 was evaluated in ELISA by IFA confirmed serum samples. Due to the low titers of IgG and IgM in Q fever patients, the standard ELISA signals were further amplified by using biotinylated anti-human IgG or IgM plus streptavidin-HRP polymer. The modified ELISA can detect 88% (29 out of 33) of Q fever patient sera collected from Marines deployed to Iraq. Less than 5% (5 out of 156) of the sera from patients with other febrile diseases reacted with the Com1. These results suggest that the modified ELISA using Com1 may have the potential to improve the detection of Q fever specific antibodies. 1. Introduction Q fever is a worldwide zoonotic disease caused by infection with Coxiella burnetii. This agent is highly infectious for humans by aerosol, where a single organism can cause the disease. Due to Q feverĄ¯s worldwide distribution and the high infectivity of C. burnetii, US military and civilian personnel deployed overseas are at high risk of being infected. Several studies [1¨C3] showed that Q fever poses a greater threat to US forces deployed in Iraq than previously predicted. An investigation of febrile illness outbreak among marines in Hit, Iraq, highlights the fact that Q fever is capable of causing localized outbreaks in exposed military personnel with attack rates up to 50% and perhaps higher [4]. The U.S. Army Center for Health Promotion and Preventive Medicine (USACHPPM) initiated a Q fever surveillance program in early 2007. Over 150 cases have been confirmed among U.S. military personnel deployed to Iraq since 2007 [5]. In addition, the largest known reported Q fever outbreak involved approximately 4,000 human cases and occurred from 2007 to 2010 in the Netherlands [6]. Acute Q fever illness most commonly presents as a flu-like illness, pneumonia, or hepatitis. Symptoms of Q fever are easily confused with those due to a variety of other pathogens (e.g., dengue, malaria, and leptospirosis) that may require different treatment regimens. The chronic form is infrequent (<5% of patients with acute infections), but the potentially consequent endocarditis is often fatal if left untreated [6, 7]. Therefore, early diagnosis to guide an appropriate treatment is critical for patient care. Although the presence of C burnetii DNA can be
%U http://www.hindawi.com/journals/ijb/2014/707463/