KAW press release about U.S. Department of Agriculture (USDA) researchers who have shown that feeding chickens the antibiotic tylosin to promote growth – not to treat disease – greatly increases the number of erythromycin-resistant Campylobacter on chicken carcasses. Erythromycin, a drug vital for treating severe food poisoning in humans, is a close cousin of tylosin. Campylobacter is the second leading cause of bacterial food borne illness in the U.S., causing an estimated 1.5 million illnesses each year with children and the elderly most often infected.