Fig 1.
Counties in California in which samples were collected.
The California counties in dark green represent high endemic counties for Lyme disease and those in light green represent low endemic counties for Lyme disease. Number and percentages of sera samples by county are provided. High endemic Lyme disease counties are defined as those with ≥ 1 case per 100,000 annually and low endemic Lyme disease counties are defined as < 1 case per 100,000 annually [16].
Fig 2.
Flowchart of testing strategies.
Testing strategy followed for the 1,700 blood donors from California. Each step of the diagram details the testing strategy and the number of samples tested.
Table 1.
Demographic characteristics of sera samples and positive Bb STTT and Bm GlpQ.
Table 2.
Testing results of sera samples for B. burgdorferi and B. miyamotoi by county.
Fig 3.
B. burgdorferi and B. miyamotoi western blot seroreactivity in blood donors from higher and lower risk counties for Lyme disease in California.
For B. burgdorferi, each run included a serum band locator (SBL) control, which shows reactivity to Lyme diagnostically significant bands at position 93, 66, 58, 45, 41, 39, 30, 28, 23 and 18 kDa and weakly reactive (WR) control, which shows reactivity to the 41 kDa band. Additionally, control serum from persons confirmed positive for B. burgdorferi or B. miyamotoi were included. Serum samples seropositive for 5 or more bands are shown. For B. miyamotoi western blots, control sera from patients confirmed positive for B. burgdorferi or B. miyamotoi were included along with a negative control serum. A monoclonal antibody to GlpQ was also included as a locator for the GlpQ antigen. The two samples with seroreactivity to GlpQ are shown.
Table 3.
Antibody testing results of human samples.