The CDC and FDA are also investigating a second similar Salmonella outbreak that has sickened 184 people in 24 states.
The outbreak has sickened 109 people in 29 states, according to the CDC.
The FLiRT variants are fueling new COVID-19 waves in some countries, but so far US markers don't show major upticks.
The illnesses were caused by Campylobacter, Salmonella, E coli, or Listeria monocytogenes.
Two of the 12 patients developed hemolytic uremic syndrome, a serious and potentially fatal kidney condition.
Uncooked chicken had the highest levels of antibiotic-resistant E coli, with similar levels found in chicken-based raw dog food.
The products, which appear pre-browned and cooked, are often cooked from a frozen state, which increases the chance that the raw chicken component may not reach a safe internal temperature.
So far 12 illnesses in 7 states are confirmed in the outbreak.
Data on Salmonella and Campylobacter bacteria from people and food-producing animals show high levels of resistance to commonly used antibiotics.
At least 10 people have been sickened by E coli in an outbreak tied to raw milk cheese, and a Salmonella outbreak linked to charcuterie meats has grown to 70 cases.
