The Center for Science in the Public Interest put out a report today detailing the "riskiest meats." It is interesting framing. Why didn't they write the article, reverse the order, and title it the "safest meats?" Probably because saying sausage and ham is relatively safe isn't as head-line grabbing as saying ground beef and chicken are relatively risky.
In any event, what I want to point out here is that the the study authors should really perform the ranking on a per pound of meat eaten (or per dollar spent) basis, as we argued should be done in this piece a month or so back in Food Safety Magazine.
Chicken is the most widely consumed meat. Thus, it shouldn't be at all surprising to find that it causes the most illnesses. There's just a lot of it. Similarly, ground beef is (I believe but could be wrong) the most widely consumed beef product. What you want to do to judge relative risk is put things on an equivalent basis - like pound-per-pound or dollar-per-dollar. In a sense, all the CSPI authors have done is ranked meats in terms of their volume of consumption.
Finally, to put things in perspective, it is important to ask whether meat, overall, is getting safer or riskier. I don't know about meat specifically, but for food generally, the CDC tracks these numbers. When you look at major, problematic pathogens like E. Coli, CDC data reveal, that laboratory confirmed cases are down today relative to a decade and a half ago. The only pathogen to experience a major rise over this time is Vibrio, which represents a small number of cases to begin with.