More Vaccines in Works To Thwart HUS E coli
A pair of USDA researchers in Ames, Iowa, have applied for patents on two vaccines they developed to curtail the growth of E. coli O157:H7 in cattle.
The research adds to similar efforts in the private sector that are now in use and in trial in the U.S. and Canada.
The vaccines are designed to prevent E. coli O157:H7 from proliferating inside cattle, which would reduce contamination of meat at the packinghouse and have other benefits.
E. coli ground beef outbreaks have been numerous in the past two years and there is currently an active restaurant steak E. coli outbreak that has involved a major recall of beef products from five restaurant chains, including Applebees and Olive Garden.
Besides combatting the dangerous spread of E. coli O157:H7 in beef, reduced shedding of the microbe into the animals’ manure would help protect produce fields, too. Manure-borne E. coli can be moved by rainfall into irrigation water, and can contaminate fruits, vegetables or other crops, increasing risk of a E. coli HUS outbreaks of foodborne illness.
The USDA vaccines were developed by Agricultural Research Service microbiologists Vijay K. Sharma and Thomas A. Casey. In preliminary tests, Holstein calves were immunized at age 3 months with a placebo or either form of the vaccine. Six weeks later, the animals were given a dose of E. coli O157:H7, and, for the next 18 days, their manure was tested for evidence of the microbe. Calves that received either vaccine had reduced or non-detectable levels of E.coli in their manure within only a few days after being inoculated with the bacteria, Sharma and Casey found.
Tags: Cattle E coli, e. coli steak
