On paper, doctors should know better — antibiotics treat only bacterial infections, and yet, physicians sometimes give them to patients who have viral infections. For patients, an unnecessary antibiotic can mean short-term side effects, like diarrhea, or more-persistent impacts, like microbiome disruption. But on a grand scale, the overuse and misuse of antibiotics pressure bacteria to gain resistance, the ability to thwart the drugs intended to kill them.

That can fuel the evolution of "superbugs" that evade most, if not all, antibiotics. In the worst-case scenario, this could contribute to tens of millions of extra deaths over the next 15 years, caused by illnesses that were once easily treated.

Given that antibiotic resistance is one of the world's leading public health threats, earlier this year, I went to Japan to investigate a program that has been remarkably effective at curbing the overuse and misuse of the drugs. I wanted to understand why doctors sometimes prescribe antibiotics when they're not needed and what approaches have been shown to improve their prescribing habits.

To answer those questions, I took a deep dive into the research on the topic and found the work of Julia Szymczak, a medical sociologist at the University of Utah School of Medicine, whose studies shed light on why doctors prescribe these medicines when they're not needed. I spoke with Szymczak about the complex social dynamics behind this behavior and whether there are reliable strategies for reining in antibiotic misuse.

Nicoletta Lanese: Could you explain the focus of your work?

Julia Szymczak: All of my work is really focused on two things. One, understanding why it is difficult for clinicians in real-world practice to use antibiotics the way that medical guidelines or evidence suggests they should be used. And then, more recently in my career, it's focused on developing interventions or strategies to help clinicians apply evidence that's informed by all that work.

I think about the decision-making about how an antibiotic is used as not simply a decision that is about pathophysiology or microbiology — it's about social dynamics. Clinicians are sensitive to a lot of other features in the care delivery environment beyond what they know to be true about antibiotics, what they know to be true or apparent about the potential infection that a patient has.

NL: What are some factors that shape that dynamic?

JS: Diagnostic uncertainty is a major challenge for clinicians. Differentiating viral versus bacterial is not [straightforward] — you don't have a slam-dunk perfect test. There are attempts to develop things to help, but the diagnostic uncertainty piece is really challenging.

Then there's the organizational characteristics around clinician decision-making, which is that everybody is incredibly time pressured, and so decision-making about antibiotics happens very quickly.

In the ambulatory or the outpatient setting, where the vast majority of human antibiotic use occurs, one of the more common themes that you will hear when you talk to clinicians is that patients often want antibiotics that are not needed. That relationship is more complicated than it appears on its face, but that is a major pressure point for clinicians.

NL: Are there other pressures that are unique to the outpatient setting, where most antibiotics are used?

JS: The major one is time pressure. I had a pediatrician who said they had — I can't remember the figure, but it was like 800 seconds for a sick visit. They broke it down into seconds. Their experience of time in the outpatient setting is so intense. Certainly clinicians in the inpatient setting [hospitals] feel time pressure, but the decision-making is distributed over an admission, which still might only be two days, but two days is different than literally five minutes.

The other thing is your interaction with that patient. That clinical encounter is very transactional, particularly in the United States, particularly for those clinicians who work in, for example, telemedicine, which is a whole other context but has similar features to urgent care or sick visits. This idea that "I'm trying to provide you with something of value" [is a big factor]. That could be a proper diagnosis. That could be the provision of a prescription. It could be reassurance that you're going to be fine. In some scenarios, people are looking for information that they can share with their employer.

Someone is coming to you to get something for a problem. Oftentimes, your assumption is that what they're coming to you for is an antibiotic. The encounter is already shaped by the patient's expectation — or your [the doctor's] expectation of the patient's expectation. There's literature that shows that, in many scenarios, clinicians might perceive that a patient wants an antibiotic when the patient actually doesn't.

Oftentimes, clinicians will say that [when] somebody has what is very likely a viral infection and they don't need antibiotics, the act of explaining why they don't need antibiotics is very difficult, particularly if they seem to want them or if they've had multiple similar episodes and they've always gotten antibiotics in the past. That discussion, the literal conversation, is difficult. It takes time. It's draining.

Then, you're in an environment where there are competing priorities around how that patient is going to evaluate your care. If a patient is unhappy because you didn't give them an antibiotic and you're concerned about the patient-satisfaction score, which is being watched by your leadership, but no one's monitoring your antibiotic use, that could tip you into the prescription of an antibiotic that isn't needed.

Then, of course, there's also the fear of missing something. On the off chance the patient has an infection and it helps them, that staves off a whole bunch of other imagined or real bad scenarios down the line.

NL: You said it's often difficult for doctors to explain their reasoning around antibiotics. Do you think that's because the technicalities of resistance are hard to explain, or something else?

JS: I don't think it's necessarily that they aren't confident in the medical explanation. A paper of mine called "I Never Get Better Without an Antibiotic" goes through all the reasons why the discussion is difficult.

Briefly: The biomedical stuff is often not the hard part. What's difficult is countering a patient who you think has already made up their mind about what they need and convincing them that they don't need it. It involves not just the provision of microbiological facts but having to explain why their past diagnoses might not have been accurate or their previous clinicians didn't make a good decision. Or people might talk about their social network: "Well, so and so got antibiotics for that." And it's like, I'm not their doctor. I didn't see them. I'm making a decision about you.

There are social reasons why that discussion is just difficult, and then you throw that into the time pressure and potentially add in even the glimmer of antagonism or conflict, and people just don't want to go there because they're exhausted.

I don't think it's about the education, about the likelihood of this being viral and "antibiotics don't work for viral infections." It's a lot more countering beliefs that aren't necessarily accurate [such as antibiotics always being needed for certain symptoms] and dealing with social awkwardness.

NL: I feel like that breaks with the common stereotype of doctors being very cold, calculating and logical.

JS: In my life of explaining to people, mostly clinical and epidemiologic audiences, there is a bit of a professional pride about evidence-based practice. Clinicians are educated deeply, and they're experts; they should be applying this evidence to every patient every time. But I always start [by saying], "You guys are human too, right?"

With antibiotics, emotions play a large role in how people are using these drugs. I've had many clinicians describe antibiotics as some of the best anti-anxiolytics — so like it's an anti-anxiety medicine for the clinician.

This idea of the cold, logical, rational actor, I mean, doesn't apply anywhere in medicine. But in particular, I think this is a great [example of a] scenario where that perfect model of decision-making just gets completely upended by contextual and structural factors, as well as social and emotional factors.

NL: Are there additional factors to consider in the context of pediatrics?

JS: A lot of my portfolio is in pediatrics, and in fact, that's where I started my work. I was a postdoctoral fellow at the Children's Hospital of Philadelphia, so I have spent a lot of time doing pediatric research.

As pediatricians say, "We have two patients: there's the child and the caregiver, the parent or the guardian." Maybe two. And so you're navigating the patient and their parents, and the interactions have a lot of complexity. There's often the challenge where the patient can't communicate what's wrong; it's difficult to convey symptoms. It adds a layer to the diagnostic uncertainty.

Then, of course, the fragility of children [is a factor], and the concern of the illness going off the rails. That feels more fearful than it does for a middle-aged adult.

But I would say one thing with pediatrics is that parents are more open to the idea of not wanting to give their kids medication that they don't need. The origins of that may come from different places than what an antibiotic steward would necessarily think of as the main reason why you want to avoid antibiotics, because it's often just about avoiding any medication. But I think that parents can be a partner in stewardship, engaging with clinicians around whether or not an antibiotic is necessary or potentially being open to this "watch and wait" — this idea of holding off to see if the body fights off the infection on its own.

When you look nationally [in the U.S.], pediatricians have done the best at improving their prescribing. Some of the biggest leaps and bounds in outpatient stewardship, it started in pediatrics. So pediatricians tend to be on the cutting edge, I would say.

NL: In pediatric outpatient settings, are there any strategies that work really well?

JS: One of the most common ones is the use of "audit with feedback," this idea of prescribing report cards where you give clinicians information at regular intervals about how well they use antibiotics and then compare it to their colleagues in their practice or in their entire health system. That's been demonstrated to work, but not in isolation.

[Editor's note: Szymczak's research suggests that certain social factors make this approach more likely to work. For instance, clinicians who respond best trust that the data they're being given is accurate, feel supported by their leadership, don't feel overly stressed or surveilled by the feedback, and are comfortable fielding patients' demands for antibiotics.]

Another piece that has been demonstrated to work, if clinicians use it, is that many electronic health records have pathways or order sets or guidelines embedded. So, if a clinician's like, "I'm going to diagnose [urinary tract infection] UTI in this patient," there's a UTI pathway that they can click on that will give them evidence-based laboratory testing and management strategies. It takes them fewer clicks to get the stuff that they need.

So, it's multifactorial, but [effective stewardship] usually involves some combination of data, education and making the right choice the easy choice.

NL: When it comes to interventions for outpatient settings, are there strategies that just don't seem to work?

JS: Education on its own, targeting clinicians or patients, is not sufficient to move the needle on prescribing.

NL: Could you elaborate on why educating patients isn't the best approach?

JS: Patient education is important but has not been demonstrated to move the needle very much. I think partially that is because the approach we have taken to education has been connected to abstract concepts like antimicrobial resistance, which is important at the population level, of course, but can be difficult to understand for the lay public and can be less motivating [for them to change their personal behaviors].

I do think we are seeing more interest from the lay public in things like the microbiome and gut health and the role of antibiotics in potentially disrupting those things. I think education to the public that directly connects to individual-level harms is more motivating than population-level harms.

NL: When it comes to interventions, do you think the surrounding cultural context affects which strategies work best? I'm thinking of the U.S. versus Japan, for instance.

JS: I do think that the surrounding cultural context will always play a role, to some degree, in how interventions to improve clinical decision-making will fare. I have also written a bit about that in another commentary that delves into the observation in the United States that we have considerable regional variation in antibiotic use that is not explained by clinical factors.

I am cautious, though, about how we think about the concept of "culture" in relation to clinical decision-making. When it comes to antibiotic prescribing, I do think there are universal factors that shape how people respond to efforts to intervene, including the management of diagnostic uncertainty; fears of missing something, leading to "just in case" prescribing; a desire to offer patients something of value; and the difficulty explaining why antibiotics are needed or not.

NL: Regarding Japan's incentive program, which pays pediatricians "tips" for improving their antibiotic use, do you think a similar approach would be motivating for U.S. pediatricians? Would it be feasible to implement that kind of strategy here?

JS: I think it could be difficult to implement here, but the details of how the program is operationalized would be very important.

We know, in general, that financial incentives have [a] mixed impact on physician decision-making. You especially have to be careful about unintended consequences. For antibiotics, it would be very important to have a clear definition of the outcome that will be incentivized and how it would be measured. With antibiotics, there can be gray areas and you don't want to incentivize undertreatment, especially if it is individual-level financial incentives.

A better approach may be in aggregate and [to] reward health systems or clinics for improved antibiotic use for conditions in which antibiotics are never needed, for example.

Editor's note: This interview has been condensed and edited for clarity.

About a decade ago, the Japanese government spotted a worrying pattern: Pediatricians were doling out a ton of antibiotics, well beyond what should be needed to treat the bacterial infections coming through their doors.

Antibiotics treat bacterial infections, not those caused by viruses, fungi or parasites. Yet doctors were often sending young patients home with antibiotics for illnesses unlikely to be bacterial. Treating nonbacterial infections with antibiotics can fuel antimicrobial resistance (AMR) and the rise of superbugs by unnecessarily exposing bacteria to the drugs, pressuring those bacteria to evolve strategies to survive. Resistant bacteria can then spread their adaptations to others, thereby compounding the problem.

In the long run, resistance could make common infections impossible to treat with existing drugs, raising the risk of serious illness and death across the population.

When pediatricians in Japan did treat bacterial infections, they were overusing the antibiotics that are likely to fuel resistance — "broad-spectrum" drugs that target many bacteria at once. When compared against 35 other high-income countries in 2015, Japan ranked dead last in the appropriateness of antibiotic choices for kids under 5.

One way to slow the development of AMR is to get antibiotic prescriptions under control. So Japan focused on one of its biggest sources of problematic antibiotic use: pediatric outpatient clinics.

"The clinics are a particular problem," said Dr. Yusuke Okubo, chief of clinical epidemiology and health services research at the National Center for Child Health and Development, a research center and hospital in Tokyo. Looking at Japan's overall antibiotic use, "90% of prescriptions are [from] outpatient clinics, not hospitals," Okubo told me. (Outpatient practices account for a similar proportion of antibiotic prescriptions in the U.S.)

A large proportion of problematic prescriptions were being written for children under 3 years old, especially those with upper respiratory tract infections, which nine times out of 10 are caused by viruses, Okubo said. The stomach bug gastroenteritis was another biggie for overprescription, despite most often being caused by a virus.

Government officials hatched an idea: What if each time a pediatrician chose not to prescribe an antibiotic in these cases, they earned a small financial reward — a tip for making a better choice? Each tip would be small, amounting to about $5 per claim at today's exchange rate, but could translate to thousands of extra dollars of annual income for individual clinics. That's no small matter for Japanese pediatricians, who Okubo estimates earn roughly $90,000 to $100,000 a year.

This incentive program, rolled out in 2018, has proved a success, so much so that it's since been expanded to cover more patients, more clinics and a wider variety of diseases. But what made the program work? I went to Japan to find out what systemic and cultural factors contributed to the program's success. Ultimately, I wanted to see whether other countries, like the U.S., could learn from this nationwide experiment.

The quietly rising threat of resistance

With bacteria, as with animals, it's survival of the fittest. When exposed to antibiotics, a percentage of bacteria die, while others survive. That surviving population has traits that help them withstand the drug's effects, which are encoded in "resistance genes." Bacteria can transfer those genes to the next generation by multiplying, as well as physically pass those genes to nearby bacteria. Plus, they can pick up new resistance genes through random DNA mutations.

All antibiotics come with the risk of pressuring bacteria to evolve resistance — it's an inherent feature of the drugs. However, broad-spectrum drugs carry the greatest risk, because they place pressure on a wider variety of bacteria than narrow-spectrum drugs do. The 2015 cross-country comparison found that Japanese doctors prescribed antibiotics with the lowest risk of resistance only 35% of the time, meaning most antibiotic prescriptions were for broader-spectrum drugs.

It's sometimes necessary to use broad-spectrum drugs — such as when an infection is resistant to narrow-spectrum options — but using broad-spectrum antibiotics when they're not needed hastens the development of AMR. So does using antibiotics for nonbacterial infections. In both scenarios, you're introducing evolutionary pressure that could have otherwise been avoided.

Globally, resistance is rising among common disease-causing bacteria; it's far outpacing the development of alternatives to antibiotics. In 2021, resistant bacterial infections directly caused 1.14 million deaths worldwide and contributed to another 3.57 million deaths. Those numbers could climb dramatically by 2050 if swift action isn't taken now.

Common pathogens already show high rates of resistance in Japan, and resistant germs contribute to thousands of deaths each year, with most occurring among older adults. People over 65 make up about 30% of Japan's population. As that percentage grows in the coming years, AMR-related illness may also increase, health officials worry.

Japan's youngest residents are also at risk, though, as resistant bacteria can sometimes pass from mothers to newborns at birth and can cause serious complications, like sepsis. Resistance has also been detected among respiratory bugs that frequently infect kids, such as Mycoplasma pneumoniae, said Dr. Takemi Murai, deputy head of the Infectious Diseases Division at Nagano Children's Hospital in Azumino. "There have been outbreaks of Mycoplasma that are resistant to antibiotics," he said.

Yet not long ago, the unrestrained use of antibiotics was a mainstay of Japanese medicine. (I'll dig into the myriad reasons why in later installments of this series.)

National insurance data sampled from 2005 showed that 60% of patients in Japan with nonbacterial upper respiratory tract infections were prescribed antibiotics, mostly broad-spectrum ones like third-generation cephalosporins, macrolides and quinolones. Most of those prescriptions came from clinics.

Something had to shift.

Tips for appropriate treatment

In 2016, Japan got serious about reducing its antibiotic misuse, releasing its first National Action Plan on Antimicrobial Resistance. It aligned with a global plan from the World Health Organization, which aimed to raise awareness of AMR and optimize the use of antimicrobials, including antibiotics, among its member states.

Two of Japan's big goals were to slash overall antibiotic use by 33% and broad-spectrum antibiotic use by 50% by 2020. The country came very close to hitting those ambitious targets by the deadline, and doing so was no small feat. The tipping program was just one of a slew of initiatives introduced to improve AMR awareness and antibiotic use.

Prior to the incentive's introduction, Japan's Ministry of Health, Labour and Welfare (MHLW) — whose role is somewhat analogous to the U.S. Department of Health and Human Services — rolled out educational campaigns for doctors and patients and wrote a manual for antibiotic use, with the first edition directed primarily at outpatient doctors. It emphasized that most acute respiratory tract infections and acute diarrheal diseases don't require antibiotics.

Among kids, children under 5 saw the highest antibiotic prescription rates, often receiving the drugs for respiratory infections. Data showed this overprescription problem was the worst in children under 3 being assessed for upper respiratory infections or acute gastroenteritis. The government's solution? Pay doctors extra to withhold antibiotics when faced with cases that don't warrant them.

"If the clinicians provide more appropriate medical services, we add additional payment," said Dr. Takuma Kato, a counselor at the Permanent Mission of Japan to the United Nations who previously worked on the incentive program for MHLW. In this case, they pay "a little bit more" when doctors don't give patients antibiotics for illnesses that are likely viral, he said.

A "little bit more" is accurate. Each tip is 800 yen, equivalent to about $7.20 when the program launched in April 2018 and about $5 at today's exchange rate.

Here's how it works: A caregiver brings in their sick infant or toddler for an initial visit, and the pediatrician determines the child likely has an acute upper respiratory tract infection or gastroenteritis. These illnesses are typically caused by viruses, so the doctor decides not to provide an antibiotic. The doctor explains this rationale to the caregiver and provides guidance for home care. If the appointment checks those boxes, the clinic can claim an extra 800 yen when they seek reimbursement.

Because mild viral infections typically resolve on their own in a few days, a strategy called "watchful waiting" can help clarify if a bacterium is actually at fault. So if a doctor does prescribe an antibiotic at the first visit, they'll often encourage the caregiver to bring the child back if their condition remains the same or worsens within a few days. The incentive and this "waiting" strategy go hand in hand.

There are a few technicalities. For example, the children being assessed must have no underlying conditions that might complicate their case, such as a weakened immune system. If children test positive on a formal diagnostic test for influenza or COVID-19, the incentive cannot be claimed. To qualify for the incentive, clinics must specialize in pediatrics and use a "comprehensive" payment system, meaning patients pay a standardized amount for the whole appointment rather than the itemized "fee for service" that is ubiquitous in the U.S.

Despite this fine print, the perk is pretty appealing for the clinics that claim it. "I think pediatric doctor associations are really happy," Okubo said.

Doctors say "small incentives add up"

The Japanese government generally incentivizes doctors to adjust their behaviors, rather than penalizing them for poor practices, Okubo said.

"It's a constructive message from the government: 'You changed your behavior, so we'll pay something,'" Okubo said. "This constructive approach motivates physicians, especially pediatricians, to apply their common sense to their actual practice."

This system is readily accepted by Japanese doctors, who have historically held a lot of political power, Kato noted. Just like in the U.S., their professional groups, such as the Japan Medical Association, lobby the government and typically push against policy proposals that they view as potential threats to their bottom line.

By contrast, an incentivizing approach is "very, very welcome, especially by the doctors' associations," said Dr. Norio Ohmagari, director of disease control and prevention at the National Center for Global Health and Medicine, part of the Japan Institute for Health Security (JIHS) in Tokyo. Ohmagari also leads the AMR Clinical Reference Center, which collaborates with the WHO on AMR countermeasures.

Doctors I asked confirmed that they like the incentive, namely because it boosts their profits.

"I apply for the pediatric antibiotic appropriate use support premium each time" it's applicable, said Dr. Yusuke Shibata, who runs the Shibata Pediatric Clinic in Asakusa, a historic district in Tokyo's Taito ward. "I appreciate the premium, as pediatric clinics already have low profits" compared with clinics that care for adults, Shibata told me in an email after I visited his clinic.

For first visits with kids under 6, clinics are paid a base rate of 6,040 to 7,210 yen, or about $38 to $45 at current exchange rates. An extra 800 yen (about $5) increases that fee by more than 10% — "a huge amount," Okubo emphasized.

Shibata estimates that his clinic sees about 30 to 40 patients with an acute respiratory infection or diarrhea each week, depending on the season. He can potentially claim the incentive for the first visit with each of these patients, assuming they don't have any conditions that would disqualify the claim.

On the high end, Shibata estimates that he might claim the incentive 180 times in a single busy month, which would total 144,000 yen, or about $900.

Dr. Atsushi Miyahara, who runs the Karugamo Clinic in the Setagaya ward in Tokyo, said he was already conservative about using antibiotics so the incentive rewards him for sticking with his status quo.

Fifteen years ago, when Miyahara opened his clinic, he noticed that other physicians prescribed a lot of antibiotics, and he questioned the practice due to the potential to fuel resistance. He provides his patients with informational flyers that explain the risks of resistance and how avoiding unnecessary prescriptions can reduce that risk. When antibiotics are needed, he predominantly uses narrow-spectrum drugs that pose a relatively low risk of resistance.

Miyahara said the local government and medical associations announced the antibiotic incentive when it was launched, and he felt its introduction has been very positive. It's increased his revenue and encouraged him to continue his stewardship practices. He estimates that for every 50 of his first visits with patients, he claims the incentive 10 to 15 times, so it applies to at least 20% of those visits.

The incentive's impact

Because some pediatric clinics qualified and others didn't — due to fee-for-service clinics being excluded — Okubo and his colleagues could directly measure whether the policy worked.

To assess the incentive's effects in its first year, the researchers looked at insurance claims from over 10,000 medical facilities from just before and after the policy's introduction. About 3,000 of the facilities qualified and claimed the incentive 316,770 times, totaling 253 million yen ($2.29 million at the time). These eligible clinics saw a 17.8% reduction in their total antibiotic use over a year without any negative effects for patients, such as higher hospitalization rates.

To see if those effects lasted, the team drew years of data from over 165,000 young children who went to either eligible or ineligible clinics. Within the first month of the policy's implementation, the former group of children saw a nearly 45% reduction in total antibiotic prescriptions, compared with the other kids. Cumulatively over the next four years, their overall antibiotic use and broad-spectrum-antibiotic use was 20% and 24% lower, respectively.

The decrease in antibiotic prescriptions did not come with an uptick in hospitalizations or healthcare costs, although there was a slight increase in the total number of doctor's visits. But that's what you'd expect as doctors track an infection over time, Okubo explained, meaning they likely employed the watchful-waiting strategy and had parents bring their kids back in if they didn't improve quickly.

Okubo's team has continued to track pediatricians' antibiotic use, and he noted that they're seeing "spillover effects" among age groups not covered by the incentive. In the under-20 age group, outpatient antibiotic prescriptions fell by 50% between 2011 and 2022. He thinks the incentive is a key driver of this trend, directly reducing prescriptions for the youngest kids while also triggering ripple effects in older groups. (This research will soon be published in a peer-reviewed journal.)

That said, there's room to improve doctors' selection of antibiotics when they are used, as the ratio of broad- to narrow-spectrum drugs is still too high. "Total antibiotic use was reduced, but its quality should be improved further," Okubo said.

The incentive's evolution

While the 800-yen tip has proved significant to clinicians, the incentive represents a very small slice of overall government healthcare spending, which totaled 468 billion yen ($3.1 billion) in 2022.

"This program is not large compared to the whole budget," Dr. Kosuke Sasaki, who works in the MHLW's health insurance bureau, told me. The program's budget has no upper limit, so if the number of claims from clinics increased, there isn't a cap on how many could be paid out. "The number of doctors using this program has increased while the number of antibiotic prescriptions has decreased since the start," Sasaki's colleague Dr. Tomonori Aoki added, noting that the government isn't concerned about how to pay that rising bill.

The program's measurable impact and low price tag may explain its growth over the years.

Every two years, Japan's Ministry of Finance hands the MHLW its slice of the government budget, and MHLW then revises the pricing for drugs, medical devices and healthcare services. The antibiotic incentive falls under this revision process and has been expanded several times.

During its first revision in 2020, the incentive was extended to children under 6. In 2022, ear, nose and throat specialists (ENTs) newly qualified for the incentive; like pediatricians, they treat many acute infections in kids and tend to overuse antibiotics, insurance data suggested. That same year, doctors could start claiming the fee for ear infections and sinus infections.

"I see a tendency for pediatric clinics to avoid prescribing antibiotics, but I do see some ENT clinics prescribing antibiotics carelessly," Shibata, the clinic owner in Asakusa, Tokyo, told me. So ENTs seem to be a logical next target.

In 2024, a separate, facility-level incentive was introduced as a complement to the 800-yen incentive. It encourages clinics to submit data to a government database that tracks antibiotic use. If first-line, narrow-spectrum antibiotics make up a certain percentage of the clinic's overall prescriptions, that clinic earns extra money, Okubo explained.

Ultimately, the 800-yen incentive helped put AMR on the radar of doctors who didn't take it as seriously as experts like Kato, who told me "AMR is kind of my life's work." Kato and researchers like Okubo see the program as a success, although they pointed to room for improvement in antibiotic selection. Ministry officials like Sasaki and Aoki said the program is easy to implement and makes a difference. Clinic doctors like Shibata and Miyahara appreciate the incentive and use it consistently. All in all, at just $5 a claim, the incentive has been remarkably effective.

In speaking with experts in Japan and the U.S., I've learned that U.S. doctors have historically faced the same pressures and showed similar lapses in antibiotic use that Japanese doctors have. However, the U.S. does not have an incentive program like Japan's. Should it launch one?

In the next installment of this series, I'll explore a central feature of this problem: the motivations behind pediatricians' antibiotic misuse. What are they, and do those motivations differ between doctors in the U.S. and Japan? Answers to those questions will help determine whether a similar incentive might have the same impact in both places.