Table 2.
Differential reactivities of commercial laboratory (N = 56) and TUES (N = 20 paired sera) samples to all four SFG Rickettsia species antigens
| Rickettsia rickettsii | Rickettsia montanensis | Rickettsia parkeri | Rickettsia amblyommii | ||
|---|---|---|---|---|---|
| Commercial | Reactivity (%) | 82.1 | 92.9 | 98.2 | 98.2 |
| Mean titer | 361.7 | 262.2 | 375.9 | 474.8 | |
| % specific reactivity | 0 | 0 | 0 | 55.4 | |
| TUES | Reactivity (%) | 92.5 | 97.5 | 90.0 | 90.0 |
| Mean titer | 2,072 | 1,234 | 1,264 | 1,340 | |
| % specific reactivity | 0 | 5 | 5 | 20.0 |
SFG = spotted fever group; TUES = Tennessee Unexplained Encephalitis Surveillance. Percent reactivity and mean titer of the sera were based on the initial immunofluorescence assay (IFA) screening while specific reactivity was based on cross-absorption of sera followed by IFA.