TABLE 2.

Prevalences of reported coinfections of humans with Borrelia burgdorferi (LD), HA, and babesiosis by geographic region

Region	Study population characteristics	Reference	No. tested	Method of determinationa			No. (%) with:
				LD	Babesia	HA	LD + babesiosis	LD + HA	HA + babesiosis	Triple coinfection
North America	LD patients
California	LD patients screened for Babesia strain WA-1	Stricker et al. (199)	255		S		60 (24)
Connecticut	LD-seropositive persons	Krause et al. (105)	735	S	S		—f (9.5)
Connecticut	LD-seropositive patients with EM rash	Magnarelli et al. (117)	40	S	S	S	3 (8)	3 (8)
Connecticut, Rhode Island	Persons with positive IgM titers for B. burgdorferi	De Martino et al. (50)	34	S		S		7 (21)
Connecticut, Rhode Island	Patients diagnosed with LD	Krause et al. (106)	240	PCR, S	PCR, S		26 (11)
Connecticut, Rhode Island	4-yr prospective study of patients with culture-proven EM rash	Steere et al. (194)	93	C	PCR, S	PCR, S	2 (2)	2 (2)	0	0
Nantucket Island	LD patients according to CDC surveillance case definition	Wang et al. (217)	171	D, S	M, S		37 (22)
New York	LD-seropositive persons	Aguero-Rosenfeld et al. (3)	175	S		S		45 (26)
	LD patients with culture-confirmed EM		42	C	S	9 (21)
New York	LD patients from areas of Babesia endemicity	Benach et al. (22)	30	S		S	20 (67)
Wisconsin, Minnesota	Patients with EM and laboratory-confirmation of LD	Mitchell et al. (128)	96	C, S	S	S	2 (2)	5 (5)		2 (2)
	HA patients
Wisconsin, Minnesota	HA patients positive by PCR	Mitchell et al. (128)	19	S	S	PCR		1 (5)	1 (5)	1 (5)
Wisconsin	Patients with HA or LD	Belongia et al. (20)	121	S		M, PCR, S		11 (9)
Wisconsin	HA patients identified through active surveillance	Belongia et al. (19)	142	S	S	M, PCR, S		7 (5)	7/102 (7)
		Other tick-borne illness
Connecticut, Nantucket Island, Rhode Island	Symptomatic patients with laboratory evidence of >1 tick-borne pathogen	Krause et al. (104)	192b	PCR, S	M, PCR, S	M, PCR, S	61 (32)	7 (4)	3 (2)	4 (2)
Massachusetts, New York	Babesiosis patients	Benach et al. (22)	41	S		S	14 (34)
		Febrile patients
Connecticut	Febrile patients with tick exposure and leucopenia or thrombocytopenia	Magnarelli et al. (118)	375c	S	S	S	22 (6)	15 (4)	2 (0.5)	2 (0.5)
Wisconsin	Patients with unexplained febrile illness during tick season	Belongia et al. (21)	62	S	M, S	M, PCR, S	0	2 (3)	0	0
New York	Prospective seroincidence: 1-yr study of adults with high-risk exposures	Hilton et al. (84)	671	S	S	S	0	0	0	0
Europe
	LD patients
Bulgaria	Patients with EM rash	Christova and Dumler (42)	145	D		S		14 (10)
Norway	Patients with acute LD	Bakken et al. (13)	58	D, S		S		6 (10)
Poland	Hospitalized LD patients	Hermanowska-Szpakowicz et al. (81)	74	D, PCR, S	PCR	PCR	0	8 (11)	0	0
Switzerland	LD-seropositive persons	Brouqui et al. (28)	70	S		S		12 (17)
Switzerland	Patients previously diagnosed with LD	Pusterla et al. (159)d	149	S		S		19 (13)
United Kingdom	LD-seropositive persons	Sumption et al. (202)	40	S		S		3 (8)
Slovenia	Other tick-borne illness: febrile pediatric patients with established tick-borne infectione	Arnez et al. (10)	28	C, D, S	S	PCR, S	0	1 (4)	0	0
Sweden	Febrile patients: prospective study of febrile patients following tick exposure	Bjöersdorff et al. (24)	27	D, S		PCR, S		3 (11)
Sweden	Community serosurvey: permanent residents of Koster Islands of Sweden; seroprevalence of HA (11%) similar to that of LD (14%)	Dumler et al. (61)	185	S		S		6 (3)

^aC, bacterial culture; D, diagnosed clinically; M, microscopy; PCR, DNA detection; S, serology.

^bA total of 310 participants enrolled with EM rash or influenza-like illness indicative of tick-borne disease; 192 (62%) of 310 had confirmed tick-borne infection. Coinfection was documented for 75 (39%) of 192 subjects.

^cOne hundred eighty (48%) of 375 patients tested demonstrated serologic evidence in acute- or convalescent-phase sera of a tick-borne disease; 47 (26.1%) of 180 had antibodies to two or more tick-borne agents..

^dThe highest seroprevalence of HA occurred among persons who were seropositive for central European TBE virus (40 of 205 [20%]).

^eEvidence of dual infection with TBE virus and B. burgdorferi sensu lato was found for 4 (14%) of 28 pediatric patients.

^fSpecific number not reported by authors.