TABLE 1.

Prevalence of resistance to antimicrobial agents among different groups of S. enterica serovar Choleraesuis isolates

Antimicrobial agent	All isolates (% resistant) (n = 199)	All isolates			PFGE cluster			PFGE gt-1a
		Human (n = 42) (% resistant)	Swine (n = 157) (% resistant)	P valuea	GA (n = 134) (% resistant)	GB (n = 65)	P valuea	Human (n = 30) (% resistant)	Swine (n = 76) (% resistant)	P valuea
Ampicillin	95	95	96	0.933	93	100	0.032	97	97	0.844
Cephalothin	1	5	0	0.007	1	0	0.463	7	0	0.030
Chloramphenicol	96	86	99	0.001	94	100	0.132	87	97	0.100
Ciprofloxacin	29	64	19	<0.001	43	0	<0.001	73	34	<0.001
Enrofloxacin	29	64	19	<0.001	43	0	<0.001	73	34	<0.001
Gentamicin	47	43	48	0.852	46	49	0.867	40	51	0.510
Nalidixic acid	99	98	100	0.053	99	100	0.485	97	100	0.110
Nitrofurantoin	47	17	55	<0.001	31	80	<0.001	13	45	0.003
Norfloxacin	29	64	19	<0.001	43	0	<0.001	73	34	<0.001
Streptomycin	61	88	54	<0.001	73	37	<0.001	93	67	0.019
Tetracycline	97	98	97	0.951	96	100	0.115	97	99	0.492
SxTb	42	86	31	<0.001	61	3	<0.001	90	49	<0.001

^aBy chi-square test.

^bSxT, trimethoprim-sulfamethoxazole.