with a susceptible strain of the same bacteria. More accurate data for all bacteria
would be necessary to estimate the extent of the differential risk for death associated
with a resistant infection vs. the risk of death associated with a susceptible infection.
But, lacking that data, the lower, more conservative estimate has been used. That
estimate is the approximation of the number of deaths derived by applying the
proportion of resistant isolates to the estimated total number of deaths caused by that
pathogen.- For several pathogens, complete data from all types of infections are not available
since tracking is limited to the more severe types of infections. For some pathogens,
such as methicillin-resistant Staphylococcus aureus (MRSA), only cases due to
invasive disease are counted. For other pathogens, where resistance is predominately
limited to healthcare settings, only disease occurring in acute care hospitals, or
requiring hospitalization, are counted.
The actual number of infections and the actual number of deaths, therefore, are
certainly higher than the numbers provided in this report.
This report does not provide a specific estimate for the financial cost of antibiotic-
resistant infections. Although a variety of studies have attempted to estimate costs in
limited settings, such as a single hospital or group of hospitals, the methods used are
quite variable. Similarly, careful work has been done to estimate costs for specific
pathogens, such as Streptococcus pneumoniae and MRSA. However, no consensus
methodology currently exists for making such monetary estimates for many of the other
pathogens listed in this report. For this reason, this report references non-CDC
estimates in the introduction, but does not attempt to estimate the overall financial
burden of antibiotic resistance to the United States.
Assessment of Domestic Antibiotic Resistance Threats
CDC conducted an assessment of antibiotic resistance threats, categorizing the threat
level of each bacteria as urgent, serious, or concerning. The assessment was done in
consultation with non-governmental experts in antibiotic resistance who serve on the
Antimicrobial Resistance Working Group of the CDC Office of Infectious Diseases
Board of Scientific Counselors (http://www.cdc.gov/oid/BSC.html).CDC also received
input and recommendations from the National Institutes of Health (NIH) and the U.S.
Food and Drug Administration (FDA).Threats were assessed according to seven factors
associated with resistant infections:
- clinical impact