Carbapenem and Cephalosporin Resistance among Enterobacteriaceae in Healthcare-Associated Infections, California, USA 1 .

We analyzed antimicrobial susceptibility test results reported in healthcare-associated infections by California hospitals during 2014-2017. Approximately 3.2% of Enterobacteriaceae reported in healthcare-associated infections were resistant to carbapenems and 26.9% were resistant to cephalosporins. The proportion of cephalosporin-resistant Escherichia coli increased 7% (risk ratio 1.07, 95% CI 1.04-1.11) per year during 2014-2017.