Researchers found that 41% of Campylobacter isolates from poultry in Kenya and Tanzania were resistant to 3 or more antibiotics.
Of backyard flock samples, 22% tested positive for Campylobacter, compared with 12% of the farm samples, and many were antibiotic-resistant.
Raw Farm (formerly Organic Pastures) of Fresno, California, has been linked to the outbreak.
The incidence of domestically acquired campylobacteriosis, pathogenic E coli infection, yersiniosis, vibriosis, and cyclosporiasis increased.
The illnesses were caused by Campylobacter, Salmonella, E coli, or Listeria monocytogenes.
The agency is urging member states to be alert for cases of drug-resistant Campylobacter in men who have sex with men.
Data on Salmonella and Campylobacter bacteria from people and food-producing animals show high levels of resistance to commonly used antibiotics.
The new detection comes just a week after the CDC warned health providers about a rise in imported measles cases.
State health officials have identified 14 people with campylobacteriosis, 12 of whom have consumed raw milk products.
The percentage of resistant infections increased by 21% for ciprofloxacin and by 27% for erythromycin.
