If you eat chicken, heads up! Consumer Reports’ tests of more than 300 raw chicken breasts purchased at stores across the country found potentially harmful bacteria in nearly all the samples. You can read its full investigation here.

Consumer Reports tested the chicken for six bacteria, including salmonella and campylobacter, which are common causes of food poisoning and E. coli and enterococcus, which are typical measures of fecal contamination.

More than half of the chicken breasts were tainted with E. coli and enterococcus.

And all the major brands tested — Perdue, Tyson, Sanderson Farms, and Pilgrims — contained worrisome bacteria, as did smaller brands and packages labeled “organic” or “no antibiotics.”  

Most troubling, when Consumer Reports looked at all of the chicken breasts tested, about half harbored at least one bacterium that was resistant to three or more common families of antibiotics.

The Food and Drug Administration has just issued voluntary new guidelines that would limit the way farmers can use antibiotics in chicken. Consumer Report says it’s a good first step but much more needs to be done.

Consumer Reports says when it comes to preparing chicken, you can’t be too careful.

The tests did not reveal any better choice, despite some differences among brands and types. You really want to make sure to cook chicken until it reaches 165 degrees in the center. It’s also important to wash your hands well after handling raw chicken.

And don’t wash raw chicken under the faucet – that can spread bacteria and increase your risk of getting sick.