New CDC Report Highlights Gains, Long Road Ahead in Fighting Antimicrobial Resistance

Nov. 17, 2019

The Centers for Disease Control and Prevention (CDC) has released a new report on the state of antimicrobial resistant infections in the United States. The report presented several concerning facts and statistics but also offered a ray of hope that some of the methods implemented to prevent the spread of antibiotic-resistant infections are working.

Read the CDC report: Antibiotic Resistance Threats in the United States 2019

The report estimated that 35,000 people die of drug-resistant infections in the United States every year. The first CDC report on antibiotic threats, published in 2013, estimated 23,000 U.S. deaths annually due to antibiotic-resistant infections. Does this mean that drug-resistant infections have nearly doubled in mortality?

The trend is fortunately not as ominous as it sounds. The CDC used new data collection and analysis techniques to make its 2019 estimates. When applying these same new techniques to the 2013 datasets, the revised estimate was 44,000 deaths, meaning that annual deaths due to antibiotic-resistant infections actually decreased by 18%.

Still, 35,000 people annually is clearly too many deaths due to drug-resistant infections. Much major news coverage quoted the fact that “every 15 minutes, someone in the U.S. dies of a drug-resistant superbug.” However, this report should provide a modicum of optimism to scientists, healthcare professionals, and community members alike. The decreased rate suggests antibiotic stewardship practices are having a positive effect, and that these efforts should be increased in both clinical and community settings.

Read more about antimicrobial stewardship in ASM’s 2-part article series on implementing stewardship in the clinical microbiology setting.

New Drug-Resistant Microbes Join Urgent Threats

Not all updates were optimistic, however. Two additional microbes joined the Urgent Threat List, a list of the infection types most threatening to human health. The list is now composed of (* = new to the 2019 Report):

  • Clostridioides (Clostridium) difficile.
  • Carbapenem-resistant Enterobacteriaceae.
  • Drug-resistant Neisseria gonorrhoeae.
  • *Carbapenem-resistant Acinetobacter.
  • *Candida auris.

Clostridioides difficile poses a threat due not only to a more virulent, fluoroquinolone-resistant strain that emerged in 2000, but also due to the overuse of antibiotics to treat other, unrelated infections. Broad-spectrum antibiotic use can inadvertently promote C. difficile diarrhea development. Because C. difficile spores are recalcitrant to antibiotic activity, this bacterium can survive treatment with antibiotics and flourish in the absence of the other microbiota, causing a gastrointestinal infection that is very difficult to treat.

To read more on C. difficile, see ASM’s recent interview with clinical microbiologist Colleen Kraft.

Neisseria gonorrhoeae infection has increased 63% since 2014, and drug-resistant gonorrhea has risen along with total incidence. The Gonoccocal Isolate Surveillance Project (GISP) was established through the CDC in 1986 to monitor drug resistance trends in N. gonorrhoeae and, among other things, has collated data around which primary antimicrobial drugs have been used to treat gonorrhea.

Distribution of antimicrobial drugs used to treat gonorrhea among participants of GISP, 1988-2017.
Distribution of antimicrobial drugs used to treat gonorrhea among participants of GISP, 1988-2017.

Another worrying trend highlighted in the report is an increase in community-acquired drug-resistant infections. Community-acquired infections are any that healthy individuals contract outside of a hospital or healthcare facility. Nosocomial infections, or hospital-acquired infections, are more likely to be drug resistant for multiple reasons, including the collection of a number of isolates in one community and the potential for hospital infrastructure to serve as reservoirs where microbes can share resistance genes. The increase in drug-resistant infections among the community suggests a higher incidence of colonization with microorganisms like methicillin-resistant Staphylococcus aureus or other drug-resistant strains or species, which can cause infection when the opportunity arises.

Antibiotics Are a One Health Issue

One Health is the idea that the health of humans, animals, and the environment are interwoven together. The CDC Report highlighted how antibiotic resistance spread is affected by activities in many ecosystems. For example, use of antibiotics in livestock animals has contributed to a rise in clinical infections in people, through many mechanisms. Though the FDA banned the use of medically important antibiotics in livestock animals for growth promotion purposes, antibiotics are still used in livestock for prevention and treatment of infections. Some organizations argue that more can be done, such as limiting duration of antibiotic use with infected animals.

Our food system is only one of many ways humans connect with their environment. Many environmental characteristics can put people at risk for infection, but the environment can also select for more dangerous pathogens. This may have been the case with one of the latest additions to the Urgent Threat List, the fungal pathogen Candida auris. This fungus is hypothesized to have gained thermal tolerance from a warming climate, allowing emergence of several lineages independently.

Read more about the role of climate change in Candida auris emergence in the mBio study.

Listen to a conversation with Amy Mathers, who studies how superbugs hide in hospital sinks.

Solving Antibiotic Resistance Problems Require Many Solutions

People in all sectors should consider what they can do to decrease the spread of antibiotic-resistant infections. Some of the proposed solutions in the Report include:

  • Infection Prevention and Control: Prevent infection and reduce the spread of germs.
  • Tracking and Data: Share data and improve data collection.
  • Antibiotic Use and Access: Improve appropriate use of antibiotics, reduce unnecessary use, and ensure improved access to antibiotics.
  • Vaccines, Therapeutics, and Diagnostics: Invest in development and improved access to vaccines, therapeutics, and diagnostics for better prevention, treatment and detection.
  • Environment and Sanitation: Keep antibiotics and antibiotics-resistant threats from entering the environment through actions like improving sanitation and improving access to safe water.

Author: Julie Wolf, Ph.D.

Julie Wolf, Ph.D.
Dr. Julie Wolf is in science communications at Indie Bio, and is a former ASM employee.