Issue No. 25: World AMR Awareness Week: U.S. Superbug Outbreaks Spread Far, Wide, and Fast

Each November, World AMR Awareness Week (WAAW) shines a spotlight on the growing global threat of drug-resistant infections — and this year’s observance could not come at a more critical moment.

The World Health Organization recently released its 2025 global antibiotic resistance surveillance report. It found that roughly one in every six bacterial infections worldwide in 2023 were antibiotic-resistant.

New CDC analyses, meanwhile, revealed that U.S. infections caused by a dangerous type of bacteria increased by more than 460% between 2019 and 2023. These infections include pneumonia, bloodstream infections, UTIs, and wound infections, and are notoriously difficult to treat.

America has also experienced outbreaks of several antimicrobial-resistant infections, from drug-resistant Shigella food poisoning to the deadly fungus Candida auris. We first covered these outbreaks in July 2023, when they made national headlines and awakened many people to the AMR crisis. Now, we’re revisiting those threats with new data and insights that shed light on where the fight against AMR stands today. 

The CDC works to detect these infections and contain their spread. But, as ever, the chief challenge is the decades-long slowdown in antibiotic innovation. According to a recent WHO analysis, there are 90 antibacterials in clinical development. Of those, only 15 are considered innovative, and just five are effective against bacteria identified as critical threats by the WHO. 

Policies called “pull incentives” — like the PASTEUR Act — are needed now more than ever to address the broken antibiotics market and spur the development of the next generation of treatments that patients need most.

Inching Closer to Superbug Catastrophe

An analysis published in the British medical journal The Lancet last fall found that antibiotic-resistant pathogens were linked to 4.7 million deaths around the world in 2021 — up from just 700,000 back in 2014. The accelerating growth in superbug deaths shows no signs of slowing anytime soon. The same Lancet analysis predicts that antibiotic resistance will contribute to the deaths of nearly 170 million people worldwide from 2025 to 2050.

These trends are deeply worrying. But to understand how AMR infections have impacted the United States specifically, it’s useful to revisit the four pathogens that made headlines in 2023 and continue to threaten the lives of people around the country.

Candida auris Cases Continue to Climb

When we last reported on C. auris, the fungal bloodstream infections were spreading dramatically. From 2019 to 2021, new cases more than tripled, from 477 to 1,553. 

Sadly, the situation has only worsened since then. In 2022, there were nearly 3,000 new infections nationwide, and in 2023, that number shot up to 4,514. In total, the CDC has identified 10,788 cases of C. auris from 2016 through 2023. A March 2025 study from the Jackson Health System in Miami confirmed that clinical cases — as well as source infections — have increased dramatically, according to reporting from Newsweek.

This is a significant increase from when C. auris first came on doctors’ radars. In 2016, there were only 51 known clinical cases of C. auris. 

And there’s reason to believe that 2024 may have brought comparable increases. Several outbreaks made the news last year. In January 2024, Washington reported its first outbreak of C. auris in a King County hospital and a skilled nursing facility in Snohomish County. Another outbreak in New Jersey last year resulted in a total of 2,281 cases in that state alone as of December 1, 2024. By April 2025, the CDC had recorded 1,052 cases nationwide. Just over three months later, that figure had nearly tripled to 2,809 cases across 21 states — already surpassing the pace of last year. Kansas, Kentucky, Mississippi, and Tennessee all reported their first-ever cases this year.

In response to growing cases over the years, the CDC increased the number of laboratories available for identifying new cases of C. auris. The agency has also released detailed guidelines for preventing infections and containing outbreaks when they do occur.

But the fact remains that, without a new generation of antifungal medications capable of fighting C. auris, this fast-spreading fungal infection will remain a real and growing danger to public health.

Deadly Pseudomonas aeruginosa Where You Least Expect It

In 2023, a Pseudomonas aeruginosa outbreak made national news when four people died after being infected through contaminated over-the-counter eyedrops. Drug-resistant forms of the bacteria Pseudomonas aeruginosa can lead to potentially deadly infections of everything from the eyes to the skin, lungs, and blood. 

New data reveals the full extent of the contamination. In February 2024, CDC researchers published the findings of an investigation into this outbreak. That episode led to 81 known infections that resulted in at least four deaths. At least another four patients needed to have their eyeball surgically removed.

In recent years, this concerning bacteria has appeared in other locations. In early 2023, for instance, almost 5 million bottles of the cleaning product Fabuloso were recalled because it was found to contain several forms of Pseudomonas, including Pseudomonas aeruginosa. A recent report from the CDC, meanwhile, confirmed that 23 people had acquired the infection from a contaminated hotel swimming pool in Maine in March 2023.

Unfortunately, some forms of Pseudomonas aeruginosa are resistant to most available antibiotics. As the CDC reports, for these strains, “treatment options are limited.” That risk is especially high inside hospitals. Drug-resistant Pseudomonas aeruginosa is responsible for 13% to 19% of healthcare-acquired infections in the United States annually. Some strains even resist a class of antibiotics usually saved for emergencies called carbapenems. These tough infections are most often seen in intensive care units, where patients are already vulnerable, and they can be deadly — killing nearly one in three people who get them.

Shigella‘s Spread Continues Apace

Two years ago, the CDC labeled the bacteria Shigella — a pathogen that can lead to a severe intestinal infection known as shigellosis — a serious public health threat.

Since then, the bacteria has continued to spread. Last year yielded a significant number of outbreaks of extensively drug-resistant forms of Shigella, meaning the bacteria were resistant to most or all available antibiotics.

In California’s Santa Clara County, the illness spread quickly among individuals experiencing homelessness. A separate outbreak in Nevada resulted in 14 cases and nine hospitalizations, although the local health agency suspects the actual case count to be far higher. Another 24 individuals tested positive for Shigella in Illinois in October — and an additional 44 developed symptoms of shigellosis.

And in Los Angeles County at the end of 2024, doctors identified three men infected with a new strain of Shigella carrying an additional genetic mutation that made it resistant to cephalosporins, antibiotics typically used when other treatments fail.

The CDC estimates that the bacteria leads to about 450,000 infections across the United States each year. But the recent uptick in extensively drug-resistant strains of Shigella is yet more proof that the current lack of antimicrobial innovation has put the health of Americans at serious risk.

Encouraging Progress in the Fight Against Gonorrhea

Two years ago, the United States first reported strains of the sexually transmitted infection that were resistant to every type of antibiotic available to treat them. Before then, gonorrhea typically responded to oral and injectable antibiotics. Now, the STI is becoming increasingly resistant to ceftriaxone, the last remaining treatment for empiric first-line gonorrhea.

Since then, all U.S. cases of gonorrhea — including drug-resistant ones — have declined. In September, the CDC reported three consecutive years of declining cases. Nevertheless, the overall number of gonorrhea infections remains high at more than 500,000 in 2024.

In good news, researchers from the nonprofit Global Antibiotic Research & Development Partnership (GARDP) and Innoviva Specialty Therapeutics announced in June of this year that the FDA has accepted their New Drug Application for zoliflodacin, a first-in-class, single-dose oral antibiotic to treat drug-resistant gonorrhea. If approved, it would be the first new antibiotic for gonorrhea in decades.

Policy Pathways to Address AMR

The current market for antimicrobials has consistently failed to sustain the development of new treatments to address the most threatening infections, largely for economic reasons. Companies have little hope of earning back development costs and remaining financially viable because, for new antimicrobial medicines to work effectively, it’s essential that they’re used judiciously. 

Maintaining research, development, and commercialization of life-saving products in this critical domain will require significant reforms to address the uniquely broken economics of the antimicrobial market. Public health experts, patient advocates, industry, academia, and more say policy solutions like the bipartisan PASTEUR Act offer the most critical path forward. 

Simply put, the policy would enable the federal government to effectively pay to ensure availability of new antimicrobials once they earn FDA approval, rather than paying per dose used. This contract model would deliver the products that patients need today and ensure that developers can financially support their antimicrobials over time, even as the drugs themselves must be used judiciously.

Without intervention, the world will remain outmatched in its fight against AMR. As we observe World Antimicrobial Awareness Week, it’s crucial to recognize solutions — like government policies that sustain the development of new antimicrobials — that better equip us to address this global threat.

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