TABLE 1.

Records with data on rates of infection of I. ricinus ticks with B. burgdorferi sensu lato in Europe^a

Country	Reference	Year(s)	Method(s)	Infection rate (%)	No. of ticks
					Total	Nymphs	Adults
Austria	117	1997	DFM	20.8	1,163	853	310
	53	1989-2002	DFM	23.2	422	211	211
Belgium	85	1996	PCR	23	489	444	45
Bulgaria	9	2000	PCR	32.7	202	90	112
	8	NG	BSK	17	47		47
Croatia	100	1995	PCR	45	124	34	90
Czech Republic	4	1995-1998	PCR	4.5	779	572	207
	48	1988-1996	DFM	20.7	8,339	3,546	4,793
	128	1987-1991	IFA	15.3	5,104	4,417	687
	50	1992	DFM	27	163	34	129
	20	2000	PCR	20.3	370	261	109
	49	1995	DFM	24.3	350	150	200
	49	1996	DFM	22	350	150	200
	49	1997	DFM	26	350	150	200
	49	1998	DFM	24.9	350	150	200
	49	1999	DFM	17.7	350	150	200
	49	2000	DFM	17.7	350	150	200
	49	2001	DFM	24	350	150	200
	53	1989-2002	DFM	21.8	1,094	586	508
	51	1991	DFM	15.2	350	150	200
	51	1992	DFM	23	350	150	200
	51	1993	DFM	22.3	350	150	200
	51	1994	DFM	19.8	350	150	200
	52	1988	GS	8.5	378		378
	47	1988-1989	DFM	20.2	460	209	251
	68	NG	DFM	7.9	570	NG	NG
	114	1997	DFM	5.4	555	145	410
	114	1998	DFM	11	163	13	150
Denmark	74	1990-1991	IFA	18.6	317	202	115
	59	1995	IFA	5.3	396	396
	59	1996	IFA	3.1	829	829
	59	1997	IFA	2.4	327	327
	60	1996	IFA	5.1	1,151	1,045	106
Estonia	79	2000	PCR	15	100		100
Finland	62	1996	PCR, DFM, BSK	32.2	726	303	423
	63	1992	BSK	5.5	1210	392	818
	79	2000	PCR	5.1	454	343	111
France	94	1994	PCR	12	249	249
	95	1995	PCR	8.2	461	461
	31	1992	IFA	9.8	1,556	1,014	542
	31	1992	IFA	6.4	1,822	1,422	400
	31	1992	IFA	4.7	1,295	811	484
	129	1991	IFA	10.7	383	314	69
	96	1994-1995, 1998	PCR	14.3	638	419	219
Germany	25	1985-1986	IFA	14.6	2,369	1,157	1,212
	26	1994	IFA	19.1	472	157	315
	27	1997	PCR	36.2	492	91	401
	97	1999-2000	PCR	35.2	1,055	507	548
	38	1992-1993	DFM	10.4	279	68	211
	38	1992-1992	DFM	4.7	1,185	1,185
	38	1992-1993	BSK	8.4	598	485	113
	38	1992-1993	IFA	12.4	194	147	47
	64	1991	IFA	18.4	414	414
	126	1992	DFM	16	100		100
	126	1993	BSK	18	100		100
	126	1994	PCR	22	100		100
	111	1996	PCR	9	3,926	3,520	406
	69	NG	PCR	18.1	226		226
	71	1987-1988	IFA	6.3	1,954	1,954
	88	1998-2000	PCR	15.8	3,138	NG	NG
	44	1999-2000	PCR	11.1	305	243	62
	65	1986	BSK	5.8	173	49	124
	98	1994	PCR	9	112	112
	90	NG	PCR	31.5	165	NG	NG
	125	1993-1994	BSK	16.3	559		559
	81	1991	DFM, IFA	17.9	756	531	225
Ireland	36	1997-1998	PCR	12	183	164	19
	37	NG	IFA	12	100	100
	66	1995	PCR	14.9	915	686	229
	34	1992-1993	IFA	2.6	2,587	2,518	69
	33	1990-1991	IFA	6.5	612	509	103
	67	1995	PCR	18.4	512	411	101
Italy	13	1994	PCR	40	227	218	9
	11	NG	PCR	4.4	420	NG	NG
	105	1997-1998	PCR	2.9	1,503	1,475	28
	12	NG	PCR	19.8	86	84	2
	24	1998	PCR	11.4	55	55
	106	NG	PCR	4.3	141	125	16
	80	1995	BSK	0	80	80
	80	1995	PCR	0	110	110
Latvia	69	NG	PCR	31.3	300		300
	23	1999	PCR	31.2	205	55	150
	23	2000	PCR	25.7	300	150	150
Lithuania	86	1988-1991	DFM	10.1	3,820	287	3,533
The Netherlands	121	NG	BSK	10.5	248	176	72
	102	1994	PCR	15.6	96	39	57
	102	1994	IFA	19.5	210	120	90
	101	1988-1993	IFA	24.6	463	341	122
	17	1991	DFM	12.5	522	476	46
Norway	58	1999	PCR	15.8	341	185	156
Poland	110	1997-1998	PCR	21.6	616	48	568
	113	2000	PCR	11.6	424		424
	108	1999	PCR	7.8	1,710	1,160	550
	122	1993	IFA	11.5	1,666	1,070	596
	7	2000	IFA	11.3	1,387	1,264	123
	7	2001	IFA	9.6	993	931	62
	93	1996	DFM, BSK	20.7	92	6	86
	93	1996	DFM, BSK	12.8	815	110	705
	83	1998	IFA	18.6	587	538	49
	83	1998	IFA	13.6	536	464	72
	107	1999	PCR	18.9	514	234	280
	127	1998	PCR	4	1,262	835	427
	127	1999	PCR	5.7	1,379	1,006	373
	127	2000	PCR	4.8	1,356	955	401
	127	2001	PCR	3.3	1,439	894	545
	14	2000	DFM	8.8	114	50	64
	14	2001	PCR	5.3	549	265	284
	112	1996	IFA	8.1	1333	554	779
	123	1994	IFA	8.8	3,958	2,395	1,563
Portugal	18	1998	PCR	75	55		55
	69	NG	PCR	14.7	217		217
Slovakia	22	1991	DFM	18.5	2,857		2,857
	29	1998	IFA	49.1	114		114
	115	1994	DFM	4.8	809	149	660
	115	1995	DFM	17.2	805	215	590
	115	1996	DFM	15.6	805	155	650
	115	1996	DFM	14.2	399	113	286
	69	NG	PCR	40.5	585		585
	21	2002	PCR	43.3	60	20	40
	42	2000	PCR	28.2	177	93	84
	43	1999	PCR	32.2	966	382	584
	43	2000	PCR	33.2	328	174	154
Slovenia	104	1990	IFA	7.7	496	411	85
	116	NG	BSK	19	363	206	157
Spain	3	1992-1993	PCR	1.5	134		134
Sweden	40	1988-1991	IFA	14.4	2974	397	2,577
	119	1994-1995	PCM	13	1,908	1,908
	28	1999	PCR	11	301		301
	120	1991	PCM	15.4	408	408
	120	1992	PCM	20.6	471	471
	120	1993	PCM	24.1	551	551
	82	1988	PCM	12.8	539	459	80
	82	1989	PCM	8.6	1,005	946	59
	5	1991	IFA	20.8	149	92	57
	56	1991	PCM	9.1	396	396
	6	1989	PCM	2	42	42
	57	1992	PCM	12.6	381	381
	57	1993	PCM	11	581	581
	57	1994	PCM	14.2	604	604
	39	NG	IFA	29.6	54	16	38
Switzerland	92	1987-1993	IFA, DFM, BSK	30.4	727		727
	54	1993	BSK	13.7	95	22	73
	84	1987	IFA	30.8	182	94	88
	75	1991	BSK	16.5	133		133
	76	NG	PCR	49	100		100
	61	1999-2001	IFA	10.9	460	415	45
	55	1993-1994	BSK	19.1	235	93	142
	109	NG	BSK	13.6	118	NG	NG
	30	1990	DFM	21.4	56	56
United Kingdom	16	1997	BSK	8.5	128	NG	NG
	72	1995-1996	PCR	4.6	680	580	100
	41	NG	PCR	7.7	65		65
	89	1994	IFA or PCR	8.3	109	73	36
	89	1995	IFA or PCR	3.9	333	221	112

^aThe total infection rate is indicated. The number of nymphs and adults examined shows the stage composition of all ticks examined (total) for each record. BSK, cultivation in BSK medium; DFM, dark-field microscopy; GS, Giemsa-stained smears; IFA, immunofluorescence assay; PCM, phase-contrast microscopy; NG, not given. The average infection rate was 13.7%, and a total of 112,579 ticks were examined.