TABLE 1 .

Prevalence of ospC alleles of B. burgdorferi in Ixodes ticks in 3 geographic areas

ospC type or subtype	Northeast			Midwest			California
	No. of ospC alleles	Prevalence	Ranka	No. of ospC alleles	Prevalence	Rank	No. of ospC alleles	Prevalence	Rank
A	57	0.144	2	30	0.068	3	22	0.111	4
B	48	0.121	3	14	0.032	11	10	0.051	8
C	15	0.038	11	6	0.014	20	0	0.000
Da	15	0.038	12	0	0.000	5	0	0.000	6
Db	0	0.000		23	0.052		17	0.086
E	16	0.040	10	6	0.014	20	1	0.005	11.5
Fa	18	0.045	7	17	0.038	2	19	0.096	5
Fb	2	0.005		33	0.074		0	0.000
Fc	0	0.000		8	0.018		0	0.000
G	10	0.025	13	13	0.029	14	12	0.061	7
Ha	21	0.053	6	0	0.000	1	0	0.000	3
Hb	1	0.003		101	0.228		25	0.126
Ib	19	0.048	8	14	0.032	11	0	0.000
J	3	0.008	16	7	0.016	18	0	0.000
K	77	0.194	1	17	0.038	9	0	0.000
L	1	0.003	17	29	0.065	4	0	0.000
M	4	0.010	15	18	0.041	8	7	0.035	9
N	37	0.093	4	20	0.045	7	0	0.000
O	6	0.015	14	8	0.018	17	0	0.000
T	17	0.043	9	13	0.029	14	1	0.005	11.5
Ua	28	0.071	5	10	0.023	11	0	0.000
Ub	0	0.000		4	0.009		0	0.000
A3	0	0.000		6	0.014	20	0	0.000
B3	1	0.003	18	2	0.005	22	0	0.000
C3	0	0.000		13	0.029	14	0	0.000
D3	0	0.000		1	0.002	23	0	0.000
E3	0	0.000		9	0.020	16	31	0.157	2
F3	0	0.000		21	0.047	6	0	0.000
H3	0	0.000		0	0.000		48	0.242	1
I3	0	0.000		0	0.000		5	0.025	10
Total	396	1.000		443	1.000		198	1.000

^a If counts were equal, then the same rank was assigned; subtypes of D, F, H, and U were combined.

^b All type I alleles were subtype Ia.