TABLE 1.

Isolation of V. cholerae O1 and O139 from clinical and environmental samples collected at Bakerganj and Mathbaria between January 2004 and May 2005^a

Yr and mo	Clinical surveillanceb						Environmental surveillancec
	Bakerganj			Mathbaria			Bakerganj			Mathbaria
	Total no. of samples	Total no. positive		Total no. of samples	Total no. positive		Total no. of samples	Total no. positive		Total no. of samples	Total no. positive
		V. cholerae O1	V. cholerae O139		V. cholerae O1	V. cholerae O139		V. cholerae O1	V. cholerae O139		V. cholerae O1	V. cholerae O139
2004
Jan.	1	0	0	2	0	0	NDd	ND	ND	ND	ND	ND
Feb.	4	0	0	2	0	0	ND	ND	ND	ND	ND	ND
March	5	0	0	3	0	0	24	0	0	12	0	2
April	10	2	0	24	13	0	24	0	0	ND	ND	ND
May	7	0	0	17	11	0	24	0	0	30	0	0
June	10	2	0	9	0	0	24	0	0	30	0	0
July	10	3	0	7	0	0	24	0	0	30	0	1 (1)
Aug.	6	1	0	1	0	0	24	0	0	51	0	0
Sept.	8	1	0	5	0	0	24	16 (4)	0	36	0	4 (1)
Oct.	18	6	0	9	0	0	24	0	0	36	0	0
Nov.	17	4	0	11	2	0	24	2	0	36	0	0
Dec.	27	11	0	11	0	0	24	1	0	36	12	0
2005
Jan.	6	0	0	11	0	0	24	1 (1)	0	54	0	0
Feb.	8	0	0	7	0	0	24	0	0	36	0	0
March	9	0	0	19	0	4	24	0	0	36	0	0
April	17	5	0	41	12	6	24	11 (2)	1 (1)	36	2	19 (3)
May	19	4	0	15	4	0	24	0	0	36	1 (1)	0
Total	182	39	0	194	42	10	360	31 (7)	1 (1)	495	15 (1)	26 (5)

^aClinical and environmental surveillance began in January and March 2004, respectively.

^bClinical samples were collected every 15 days for three consecutive days.

^cEnvironmental samples were collected monthly in Bakerganj and biweekly in Mathbaria. Numbers in parentheses indicate strains isolated from LA plates, based on a positive CBH signal.

^dND, not done.