There are plenty of reasons why we need to bring this pandemic to a swift end. With each day, thousands more people die, and hundreds of thousands more become infected, while the ongoing disruption to daily lives, business, trade and travel is costing countless people their jobs as more businesses go under and economies continue to sink. But another important and less talked-about reason why we need to end it sooner rather than later is that the longer this crisis continues, the weaker we will be when it comes to fighting the next one. Because with each day, this crisis is helping to fuel another, silent pandemic: that of antimicrobial resistance, or AMR.

Even before COVID-19, AMR was widely seen as one of the biggest threats to human health. Over time and repeated exposure, pathogens can build up resistance to the very drugs designed to treat them—especially with suboptimal use—eventually rendering them ineffective and the infections untreatable. Unless done judiciously, the more these drugs are used, the sooner this is likely to happen. Since the beginning of the pandemic, in the absence of effective treatments against COVID-19, the use of antibiotics to treat infected patients has been extensive. This has raised fears that it could exacerbate the global spread of AMR, leading to more deaths from once treatable infections and in the process undermining our ability to fight the next pandemic.

That fact that there will be a next one is not up for debate. The relentless nature of how viruses and bacteria mutate means that novel pathogens with pandemic potential will continue to emerge. So, it’s not a question of if there will be another pandemic, but when. Moreover, the same evolutionary forces that make this a certainty are also driving the spread of AMR.

This places us in a difficult position. Antibiotics, a class of antimicrobial drug where resistance has been a growing problem, have an important role to play during viral outbreaks, for example when patients have bacterial co-infections or develop secondary bacterial infections. During the 1918 flu pandemic, which killed 50–100 million people, 95 percent of those who died had these kinds of bacterial infections. Since then, the availability of antimicrobials has reduced the risk of bacterial infections during viral outbreaks, and indeed at the beginning of COVID-19, in the absence of any other known effective treatments, antibiotics have been commonly used as a frontline defense in treating hospitalized patients.

It is still unclear to what extent this was warranted. Any clinician faced with a critically ill COVID-19 patient with the potential to develop a drug-resistant infection is naturally going to err on the side of caution and give them a broad spectrum of antibiotics. However, the extent to which bacterial infections have contributed to COVID-19 morbidity and mortality is still emerging, with some studies suggesting that only 3.5 percent of patients in the U.S. had co-infections and just 14.3 percent went on to develop secondary infections. And while this could partly be attributed to the prudent use of antibiotics, evidence suggests that in 72 percent of cases where COVID-19 patients in the U.S. received antibiotics, it was not actually clinically warranted.

In contrast, in many low- and middle-income countries, where many antibiotics are not available, either because they are not registered with the regulatory authority or are simply too expensive, countless COVID-19 patients will have developed bacterial infections that have gone untreated. This can allow bacteria to continue to circulate and, if later treated suboptimally, increase the potential for resistance to develop. The combination of inappropriate use of antibiotics when not needed, and not having access to them when they are, both help increase the spread of AMR.

So, even though some COVID counter measures, such as widespread physical distancing, have the potential to slow the spread of AMR by reducing transmission of drug-resistant bacteria and reducing viral infections inappropriately treated with antimicrobials, our response to this pandemic, implemented on a massive scale, is likely to actually accelerate its spread. Before the pandemic, AMR was thought to be responsible for at least 700,000 deaths a year and on the rise. However, in the wake of COVID-19, this may well increase further.

Clearly, there is an urgent need for new antibiotics and antimicrobials to be developed, and adherence to established antibiotic stewardship programs need to be more closely observed. In the midst of the current pandemic that may be challenging, when clinicians are struggling to save the lives of COVID-19 patients. So, our best bet is to end the acute phase of this pandemic as quickly as possible through vaccination.

Under nonpandemic conditions, vaccines are already one of our most effective weapons against AMR. There is clear evidence that vaccination not only prevents the spread of certain bacteria and prevents resistance from occurring, but it also significantly curtails the use, and misuse, of antibiotic drugs every year by preventing infections in the first place. So, while COVID-19 vaccines will be essential to ending the pandemic, and in reducing the spread of AMR, vaccines against other diseases also have a role to play.

But as the race to make COVID-19 vaccines available continues, there is another way in which vaccination can help. The speed at which the world has rallied to develop these vaccines, and make them equitably available, also provides a good global model for how we collectively tackle AMR, which hasn’t seen anywhere near the kind of investment as COVID-19, despite being a rapidly escalating threat with the potential to cause the same kind of global devastation.

A similar collaborative approach could help provide a framework for the challenge of developing new antimicrobial drugs and making them equitably available too. Because even though antibiotics have almost certainly saved thousands of lives during this pandemic, and even though a lack of access to antibiotics still kills more people than antimicrobial resistance, unless we develop new drugs that will almost certainly change.