ELISAs for differentiation of acute and chronic Q fever
A new range of ELISAs provides differentiated analysis of antibodies against Coxiella burnetii, the causative agent of Q fever. According to Immunological Methods for the Detection of Infectious Diseases (MiQ. 2017), separate detection of antibodies against phase 1 and phase 2 antigens of C. burnetii is recommended to aid discrimination of acute and chronic infections. Acute primary infections are characterized by IgM and later IgG antibodies against phase 2 antigens, while antibodies against phase 1 antigens occur only in chronic infections. Three new ELISAs from EUROIMMUN provide sensitive detection of IgM or IgG antibodies against phase 2 antigens or IgG antibodies against phase 1 antigens and thus support the differentiation of acute and chronic C. burnetii infections. In evaluation studies with precharacterized sera the three ELISAs demonstrated high sensitivities and high specificities, underlining their suitability for use in screening analyses. The ELISAs are fully automatable.
Q fever occurs worldwide and is transmitted to humans by direct or indirect contact with infected animals, consumption of unpasteurized milk or bites from infected ticks. Acute infections manifest with mild flu-like symptoms, whereby complications such as atypical pneumonia or remittent fever can occur. Chronic courses are characterized by infection durations of more than six months and mostly lead to chronic endocarditis. Diagnosis of Q fever is based primarily on serological methods.