Table 3.
Results of Xenodiagnostic Testing
| Group | ID | Protocol | No. of Fed Ticks Tested by PCR/Culture | No. of Positive Ticks | No. of Fed and Partially Fed Larvae Tested by IA/PCR/ESI-MS | No. of IA/PCR/ESI-MS Positive Results |
|---|---|---|---|---|---|---|
| EM | A-01 | 2 | 6 | 0 | 4 | 2 |
| EM PTxa | A-01R | 2 | ND | ND | 10 | 0 |
| EM PTx | B-01 | 1 | 0 | N/A | N/A | N/A |
| EM PTx | B-02 | 1 | 1 | 0 | N/A | N/A |
| EM PTx | B-03 | 1 | 2 | 0 | N/A | N/A |
| EM PTx | B-04 | 1 | 8 | 0 | N/A | N/A |
| EM PTx | B-05 | 2 | 11 | 0 | 11 | 0 |
| High C6 | C-01 | 1 | 0 | N/A | N/A | N/A |
| High C6 | C-02 | 1 | 1 | 0 | N/A | N/A |
| High C6 | C-02R | 2 | ND | ND | 21 | 0 |
| High C6 | C-03 | 1 | 1 | 0 | N/A | N/A |
| High C6 | C-03R | 2 | ND | ND | 9 | 0 |
| High C6 | C-04 | 1 | 5 | 0 | N/A | N/A |
| High C6 | C-04R | 2 | ND | ND | 24 | 0 |
| High C6 | C-05 | 1 | 1 | 0 | N/A | N/A |
| High C6 | C-06 | 1 | 0 | N/A | N/A | N/A |
| High C6 | C-06R | 2 | ND | ND | 23 | 0 |
| High C6 | C-07 | 1 | 0 | N/A | N/A | N/A |
| High C6 | C-07R | 2 | ND | ND | 20 | 0 |
| High C6 | C-08 | 2 | 8 | 0 | ND | ND |
| High C6 | C-09 | 2 | 19 | 0 | ND | ND |
| High C6 | C-10 | 2 | 9 | 0 | ND | ND |
| PTLDS | D-01 | 1 | 0 | N/A | N/A | N/A |
| PTLDS | D-02 | 1 | 5 | 1 | N/A | N/A |
| PTLDS | D-02R | 2 | 1 | 0 | 1 | 1 |
| PTLDS | D-03 | 1 | 0 | N/A | N/A | N/A |
| PTLDS | D-04 | 1 | 7 | 0 | N/A | N/A |
| PTLDS | D-05 | 2 | 22 | 0 | ND | ND |
| PTLDS | D-06 | 2 | 24 | 0 | ND | ND |
| PTLDS | D-07 | 2 | 15 | 0 | ND | ND |
| PTLDS | D-08 | 2 | 7 | 0 | 5 | 0 |
| PTLDS | D-09 | 2 | ND | ND | 24 | 0 |
| PTLDS | D-10 | 2 | 5 | 0 | 5 | 0 |
| HV | E-01 | 1 | 0 | N/A | N/A | N/A |
| HV | E-02 | 1 | 1 | 0 | N/A | N/A |
| HV | E-03 | 1 | 0 | N/A | N/A | N/A |
| HV | E-04 | 1 | 3 | 0 | N/A | N/A |
| HV | E-05 | 1 | 0 | N/A | N/A | N/A |
| HV | E-06 | 1 | 0 | N/A | N/A | N/A |
| HV | E-07 | 1 | 2 | 0 | N/A | N/A |
| HV | E-08 | 1 | 0 | N/A | N/A | N/A |
| HV | E-09 | 2 | 8 | 0 | 10 | 0 |
| HV | E-10 | 2 | 11 | 0 | 11 | 0 |
Abbreviations: EM, erythema migrans; EM PTx, after completing antibiotic therapy for erythema migrans; High C6, subjects with persistently elevated C6 antibody serum levels; HV, healthy volunteers; IA/PCR/ESI-MS, isothermal amplification followed by polymerase chain reaction and electrospray ionization mass spectroscopy; N/A, not applicable; ND, not done; PCR, polymerase chain reaction; PTLDS, posttreatment Lyme disease syndrome; R, repeat xenodiagnostic procedure.
a Procedure was repeated 7 months after completing antibiotic therapy and the patient was asymptomatic. Nymphal ticks were tested by PCR and culture in protocol 1; larval ticks were tested in protocol 2. Direct testing of ticks by IA/PCR/ESI-MS was performed only under protocol 2. Individual ticks were evaluated by only 1 of the 2 methods.