Superbugs List: World Health Organization Names Top 12 Threats

On Monday, the World Health Organization released a list of 12 bacterial "superbugs" that "pose the greatest threat to human health" because they are resistant to most or all known antibiotic medicines.

According to the Centers for Disease Control and Prevention, 23,000 Americans die each year from infections resistant to antibiotics and at least 2 million people become infected with drug-resistant bacteria.

The WHO superbug list has three tiers. The critical tier consists of bacteria that are still fairly rare but are resistant to all or nearly all known antibiotics. Although most people won’t be affected by these bacteria (at least not yet), they require a tremendous amount of time and resources to treat when they do occur. Many who are infected die because the diseases don't respond to drugs.

The second and third tier bacteria strains are resistant to some, but not all, antibiotics. Streptococcus pneumoniae is resistant to penicillin and can cause pneumonia, ear and sinus infections, meningitis, and blood infections, according to Scientific American.

Not included on the list is a resistant strain of bacteria that causes tuberculosis, because scientists have already begun the process of finding new antibiotics for that bacteria, Scientific American reported.

Scientists generally theorize that overuse of antibiotics is responsible for the resistant strains, and now part of the problem is that new antibiotics are not being developed quickly enough to keep up with the mutations of some strains of bacteria.

Without effective treatments, the highly resistant bacteria could become more widespread and lead to a public health crisis in which a large number of people become infected.

Here are the 12 superbugs on the WHO list:

Priority 1: CRITICAL

• Acinetobacter baumannii, carbapenem-resistant
• Pseudomonas aeruginosa, carbapenem-resistant
• Enterobacteriaceae, carbapenem-resistant, ESBL-producing

Priority 2: HIGH

• Enterococcus faecium, vancomycin-resistant
• Staphylococcus aureus, methicillin-resistant, vancomycin-intermediate and resistant
• Helicobacter pylori, clarithromycin-resistant
• Campylobacter spp., fluoroquinolone-resistant
• Salmonellae, fluoroquinolone-resistant
• Neisseria gonorrhoeae, cephalosporin-resistant, fluoroquinolone-resistant
   

Priority 3: MEDIUM

• Streptococcus pneumoniae, penicillin-non-susceptible
• Haemophilus influenzae, ampicillin-resistant
• Shigella spp., fluoroquinolone-resistant

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