PCR assay with C. burnetii performed with primers of nested PCR as described in the materials and methods. Lanes: 1, negative control of first PCR; 2, negative control of nested PCR; 3, 100 bp DNA ladder; 4, C. burnetii suspension 1×; 5, C. burnetii suspension 10×; 6, C. burnetii suspension 102×; 7, C. burnetii suspension 103×; 8, C. burnetii suspension 104×; 9, C. burnetii suspension 105×; 10, C. burnetii suspension 106×; 11, C. burnetii suspension 107×; 12, C. burnetii suspension 108×; 13, C. burnetii suspension 109×; 14, C. burnetii suspension 1010×; 15, C. burnetii suspension 1011×; 16, C. burnetii suspension 1012×; and 17, C. burnetii suspension 1013×.