Biggest Threats and Data

Antibiotic resistance is one of the biggest public health challenges of our time. In 2013, CDC published a comprehensive analysis outlining the top 18 antibiotic-resistant threats in the U.S., titled Antibiotic Resistance Threats in the United States, 2013 (AR Threats Report). The report sounded the alarm to the danger of antibiotic resistance, stating that each year in the U.S., at least 2 million people get an antibiotic-resistant infection, and at least 23,000 people die.

The report ranked the 18 threats (bacteria and fungi) into three categories based on level of concern to human health—urgent, serious, and concerning—and identified:

  • Minimum estimates of morbidity and mortality from antibiotic-resistant infections
  • People at especially high risk
  • Gaps in knowledge about antibiotic resistance
  • Core actions to prevent infections caused by antibiotic-resistant bacteria, and slow spread of resistance
  • What CDC was doing at that time to combat the threat of antibiotic resistance

The data below is pulled from the 2013 Threats Report. CDC is working towards releasing an updated AR Threats Report in fall 2019.

On This Page

Urgent Threats

Clostridioides difficile

Medical illustration of C. difficile

Type: Bacteria

Also known as: C. difficile or C. diff, previously Clostridium difficile

About: C. difficile causes life-threatening diarrhea and colitis (an inflammation of the colon), mostly in people who have had both recent medical care and antibiotics

Infections per year: 500,000*

Deaths per year: 15,000*

Learn more: CDC’s C. difficile website

*Updated data from a 2015 CDC study. This data is not reflected in the AR Threats Report.

Carbapenem-resistant Enterobacteriaceae (CRE)

Medical illustration of CRE

Type: Bacteria

Also known as: Nightmare bacteria

About: Some Enterobacteriaceae (a family of germs) are resistant to nearly all antibiotics, including carbapenems, which are often considered the antibiotics of last resort

Drug-resistant infections per year: 9,000

Deaths per year: 600

Learn more: CDC’s CRE website

Drug-resistant Neisseria gonorrhoeae

Medical illustration Of gonorrhea

Type: Bacteria

About: N. gonorrhoeae causes the sexually transmitted disease gonorrhea, and has progressively developed resistance to the antibiotic drugs prescribed to treat it

Infections per year: 246,000

Learn more: CDC’s antibiotic-resistant gonorrhea website

Serious Threats

Multidrug-resistant Acinetobacter

Medical illustration of acinetobacter

Type: Bacteria

About: People with weakened immune systems, including hospitalized patients, are more at risk of getting an Acinetobacter infection, which is resistant to many commonly prescribed antibiotics

Multidrug-resistant infections per year: 7,300

Deaths per year: 500

Learn more: CDC’s Acinetobacter website

Drug-resistant Campylobacter

Medical illustration of campylobacter

Type: Bacteria

Also known as:  Campy

About: Campylobacter usually causes diarrhea, fever, and abdominal cramps, and can spread from animals to people through contaminated food, especially raw or undercooked chicken

Drug-resistance infections per year: 310,000

Learn more: CDC’s Campylobacter website

Fluconazole-resistant Candida

Medical illustration of fluconazole-resistant Candida

Type: Fungus

About: Candida yeasts normally live on skin and mucous membranes without causing infection; however, overgrowth of these microorganisms can cause symptoms to develop

Fluconazole-resistant Candida infections per year: 3,400

Deaths per year: 220

Extended-spectrum Beta-lactamase (ESBL) producing Enterobacteriaceae

Medical illustration of CRE

Type: Bacteria

Also known as: ESBL, or extended-spectrum β-lactamase 

About: ESBL-producing Enterobacteriaceae are resistant to strong antibiotics, including extended spectrum cephalosporins

  • ESBL is an enzyme that allows bacteria to become resistant to a wide variety of penicillin and cephalosporin drugs
  • Bacteria that contain this enzyme are known as ESBLs or ESBL-producing 

Drug-resistant infections per year: 26,000 

Vancomycin-resistant Enterococcus (VRE)

Medical illustration of Vancomycin-resistant Enterococcus (VRE)

Type: Bacteria

Also known as: VRE

About: Enterococci cause a range of illnesses, mostly among patients receiving healthcare

Drug-resistant Enterococcus infections per year: 20,000 

Deaths per year: 1,300

Learn more: CDC’s VRE in Healthcare Settings website

Multidrug-resistant Pseudomonas aeruginosa

Medical illustration of multidrug-resistant Pseudomonas aeruginosa

Type: Bacteria

Also known as: P. aeruginosa

About: Serious Pseudomonas infections usually occur in people with weakened immune systems, making it a common cause of healthcare-associated infections 

Multidrug-resistant Pseudomonas infections per year: 6,700 

Deaths per year: 440

Learn more: CDC’s P. aeruginosa in Healthcare Settings website

Drug-resistant non-typhoidal Salmonella

Medical illustration of Drug-resistant non-typhoidal salmonella

Type: Bacteria

  • Non-typhoidal Salmonella includes serotypes (a subdivision of a species) other than Typhi, Paratyphi A, Paratyphi B, and Paratyphi C 

About: Salmonella spreads from animals to people mostly through food, and usually causes diarrhea, fever, and abdominal cramps 

Drug-resistant Salmonella infections per year: 100,000

Learn more: CDC’s Salmonella website

Drug-resistant Salmonella Serotype Typhi

Medical illustration of drug-resistant Salmonella serotype typhi

Type: Bacteria

Also known as: typhoid fever

About: Salmonella Typhi causes a serious disease called typhoid fever, and is spread by contaminated food and water

Drug-resistant Salmonella Typhi per year: 3,800

Learn more: CDC’s Typhoid Fever website

Drug-resistant Shigella

Medical illustration of shigella

Type: Bacteria

About: Shigella spreads in feces through direct contact or through contaminated surfaces, food, or water, and most people infected with Shigella develop diarrhea, fever, and stomach cramps

Drug-resistant infections per year: 27,000

Learn more: CDC’s Shigella website

Methicillin-resistant Staphylococcus aureus (MRSA)

Medical illustration of methicillin-resistant Staphylococcus aureus (MRSA)

Type: Bacteria

Also known as: MRSA, resistant staph (short for Staphylococcus), resistant S. aureus

About: MRSA is S. aureus that has become resistant to certain antibiotics called beta-lactams, including methicillin

  • Patients in healthcare settings frequently get severe or potentially life-threatening infections, and people can also get MRSA in their community

Severe MRSA infections per year: 80,461 

Deaths per year: 11,285 

Learn more: CDC’s MRSA website

Drug-resistant Streptococcus pneumoniae

Medical illustration of drug-resistant Streptococcus pneumoniae

Type: Bacteria

Also known as: S. pneumonia, pneumococcus

About: S. pneumoniae causes pneumococcal disease, which can range from ear and sinus infections to pneumonia and bloodstream infections 

Drug-resistant infections per year: 1.2 million 

Hospitalizations per year: over 19,000 

Deaths per year: 7,000 

Learn more: CDC’s S. pneumoniae website

Drug-resistant Tuberculosis

Medical illustration of tuberculosis

Type: Bacteria

Also known as: TB, multidrug-resistant TB (MDR TB), or extensively drug-resistant TB (XDR TB), Mycobacterium tuberculosis (M. tuberculosis)

About: TB is caused by the bacteria M. tuberculosis, and is among the most common infectious diseases and a frequent cause of death worldwide 

Drug-resistant TB cases in 2011: 1,042 

Learn more: CDC’s TB website

Concerning Threats

Vancomycin-resistant Staphylococcus aureus (VRSA)

Medical illustration of vancomycin-resistant Staphylococcus aureus

Type: Bacteria

Also known as: VRSA, resistant staph (short for Staphylococcus), resistant S. aureus

About: VRSA is S. aureus that has become resistant to the antibiotic vancomycin, the antibiotic most frequently used to treat serious S. aureus infections 

Cases 2002-2013: 13 in 4 states 

Learn more: CDC’s VRSA website

Erythromycin-resistant Group A Streptococcus

Medical illustration of erythromycin-resistant Group A Streptococcus

Type: Bacteria

Also known as: resistant group A strep, GAS 

About: Group A strep can cause many different infections that range from minor illnesses to very serious and deadly diseases, including strep throat, scarlet fever, and others 

Drug-resistant infections per year: 1,300 

Deaths per year: 160 

Learn more: CDC’s GAS website

Clindamycin-resistant Group B Streptococcus

Medical illustration of clindamycin-resistant Group B Streptococcus

Type: Bacteria

Also known as: resistant group B strep, GBS

About: Group B strep can cause severe illness in people of all ages 

Drug-resistant infections per year: 7,600 

Deaths per year: 440 

Learn more: CDC’s GBS website