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Volume 13, Number 12—December 2007

Escherichia coli O157:H7 in Feral Swine near Spinach Fields and Cattle, Central California Coast1

Michele T. Jay*Comments to Author , Michael Cooley‡, Diana Carychao‡, Gerald W. Wiscomb§, Richard A. Sweitzer¶, Leta Crawford-Miksza*, Jeff A. Farrar#, David K. Lau**, Janice O’Connell*, Anne Millington#, Roderick V. Asmundson**, Edward R. Atwill, and Robert E. Mandrell‡
Author affiliations: *California Department of Public Health, Richmond, California, USA; †University of California, Davis, California, USA; ‡US Department of Agriculture, Albany, California, USA; §US Department of Agriculture, Sacramento, California, USA; ¶University of North Dakota, Grand Forks, North Dakota, USA; #California Department of Public Health, Sacramento, California, USA; **US Food and Drug Administration, Alameda, California, USA;

Main Article

Table 1

Escherichia coli O157:H7 isolated from environmental samples collected at ranch A, California, September–November 2006

Sample type No. tested No. positive (%) No. matches*
Cattle feces 77 26 (33.8) 15
Cattle water trough 10 0 NA
Compost (chicken pellets)† 1 0 NA
Feral swine
Necropsy 40 2 (5) 2
Buccal swab 8 0 NA
Colonic feces 40 2 (5) 2
Rectal-anal swab 8 0 NA
Tonsil 8 0 NA
Feces from ground 47 11 (23.4) 6
Subtotal 87 13 (14.9) 8
Other animal specimens‡ 26 0 NA
Surface water§ 79 3 (3.8) 2
Soil/sediment 37 3 (8.1) 3
Well/irrigation water¶ 18 0 NA
Total 335 45 (13.4) 28

*No. samples indistinguishable from the major spinach-related outbreak strain by pulsed-field gel electrophoresis (XbaI-BlnI PulseNet profile EXHX01.0124-EXHA26.0015). NA, not applicable.
†Commercial, heat-treated chicken manure.
‡Included feces from coyote (n = 1), deer (n = 4), dog (n = 1), horse (n = 2), sheep/goat (n = 3, composite), waterfowl (n = 2), unknown species (n = 11), and owl (n = 2).
§Surface water (rivers, streams, ponds) was sampled by collection of 100-mL grab samples or placement of a modified Moore swab for 4–5 d.
¶Well water was sampled from 3 wells or sprinkler heads by collection of 100-mL or 1,000-mL grab samples or by concentration of 40,000 mL to 500 mL by using ultrafiltration (7).

Main Article

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Main Article

1This work was presented in part as a poster at the 107th General Meeting of the American Society for Microbiology, Toronto, Ontario, Canada, May 24, 2007.

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