A new British study says vaccinating cattle against E. coli
0157:H7 could cut food poisonings from the poison-producing bacteria by up to
85 per cent.
The report, published this week in the National Academy of
Sciences journal in the United Kingdom, comes just as Bioniche Inc. of
Brockville, Ont., has decided to sell its animal-products division, including
the E.coli vaccine for cattle that was the basis for the study.
The research team says few farmers are using the vaccine,
which costs about $6 per animal, because it does nothing to improve the health
of their cattle.
Cattle vaccines effectively halve the frequency
of shedding of the bacteria, the authors say.
But because of the role played by supershedders,
the human benefit of vaccine use in cows should be “substantially greater than
anticipated from the observed efficacy,'' and could be underestimated by those
who don't take the supershedder effect into consideration, they write.
“Specifically, we show that vaccines producing a
50 per cent reduction in shedding frequency in cattle (consistent with reported
efficacies) could reduce human cases by nearly 85 per cent. We conclude that
vaccination of cattle, the major reservoir for E. coli O157, could be an
especially effective public health control against a serious disease.''