On Wednesday, Alex Azar, President Donald Trump's secretary of health and human services, testified that he could not guarantee that a COVID-19 vaccine would be made available to all Americans who need it. "We would want to ensure that we work to make it affordable," he said, "but we can't control that price, because we need the private sector to invest. The priority is to get vaccines and therapeutics. Price controls won't get us there."

Azar's logic here — that without the ability to set their own prices and to make a significant profit, private sector pharmaceutical companies would simply refuse to work on a vaccine or medication — might seem cruel in the face of a new, potentially scary epidemic disease. But it is not surprising. For decades, the pharmaceutical industry and its allies have argued that punishingly high drug prices are necessary if Americans wish to have new medications and innovative care. Without high profits to drive innovation, they argue, U.S. pharmaceutical companies would shutter, making their therapeutics unavailable even to those who could afford them.

But what they and Azar miss is that profit is not the only driver of innovation, and indeed relying on a profit-driven health care system undermines the health and safety of all.

It wasn't always this way. Take the example of the famously innovative physician and researcher Jonas Salk more than 65 years ago. When Salk's team developed an effective polio vaccine that was approved for public use, he refused to patent it. Who owns the patent? "Well, the people, I would say," he told journalist Edward R. Murrow in 1955. "There is no patent. Could you patent the sun?"

The interview, which aired on the same day the successful vaccine was announced, quickly became the stuff of legend, and Salk continues to be celebrated for his scientific achievements as well as his lack of concern with what undoubtedly could have been tremendous profits.

Why would Salk and his team have worked so diligently, surmounting so many barriers to develop a vaccine if not for profit? Why innovate when profit is completely off the table?

The story of how Salk developed the polio vaccine points to some answers.

Polio was a stunningly horrific ailment that at midcentury was a scourge of children despite the sanitation developments that had resulted in decreased childhood mortality overall. A tenacious virus, polio continued to strike American communities all across the country: rich and poor; urban, suburban and rural. In the 1940s and 1950s, between 13,000 and 20,000 paralytic cases were reported annually.

Ordinary people could see with their own eyes the impact of the disease, and they were probably particularly motivated to participate, even in a small way, in what they saw as combating the number one menace to the public health.

Salk and his team worked with both public and private funders to research and develop the vaccine, and they used publicity and public engagement in the process. The nonprofit National Foundation for Infantile Paralysis (now March of Dimes), founded by President Franklin D. Roosevelt in 1938 and supported by his famous annual Birthday Balls until his death in 1945, was instrumental in raising the funds, awareness and public trust to run the trials needed to develop the vaccine, and millions of Americans participated in those fundraising efforts.

Salk and his team understood they needed to marshal enormous public trust to pull off a large-scale clinical trial that used 1.4 million American schoolchildren, called the "polio pioneers," as test subjects in their historic double-blind clinical trial. The team had been working with public as well as nonprofit sectors, and the federal government was at times even willing to speed through some serious ethical concerns to get a vaccine as quickly as possible.

Because of this tremendous public participation, the team determined that the public had already paid for the vaccine and should be provided with guarantees of safety, at minimal or no cost.

The political economy of the 1950s also shaped Salk's approach to his work. Salk was not personally against capitalism, and U.S. medicine in the 1950s was anything but socialist. Yet he and others understood implicitly that unbridled capitalism, where the market alone would set the price for this lifesaving, life-course-altering vaccine, would jeopardize their entire enterprise.

Universal no-cost or low-cost access to the vaccine was understood to be central to the success of the vaccination campaign and the eradication of polio. Letting the market determine the drug price would have only limited access to the vaccine, compromising its efficacy and needlessly risking the health of millions of children.

It also would have impeded the vaccine's very development. Why would a family volunteer to participate in a risky drug trial for something they might never be able to afford? Because of the "herd immunity" required for vaccines to be effective, limiting access to only those people who could afford a drug meant undermining the protection that would be afforded by herd immunity.

The same principle would hold with any theoretical vaccines or therapeutics developed to combat COVID-19 today. Whatever innovations emerge, they will need to be accessible to everyone if they stand a chance at protecting anyone.

If the 1950s seem like too long ago to be truly relevant to today's complicated health care landscape, consider the innovation that price controls have actually spurred more recently in other countries. Take for example Japan, which famously has strict price controls with one government-mandated price book for every medical procedure performed in the country. When the Japanese government decided to lower the price of MRI scans far below the rates that people had been paying, the Japanese companies Hitachi and Toshiba innovated and developed lower-cost, high-quality MRI machines that are now marketed and sold all around the world.

The problem of polio required mass public cooperation, huge financial research and development investment, and public trust in science and scientific researchers. For the Salk vaccine team, that meant that a patent would be impossible and ineffective, not to mention unethical — much like patenting the sun.

Today, if we are to support our public health experts and excellent biomedical researchers in their efforts to develop a vaccine and other therapeutic innovations for COVID-19, we will need to give them our cooperation, sufficient resources and, most importantly, our trust. In turn, they should have to make their innovations accessible and affordable for all of us.

Deborah Levine is a historian of medicine and associate professor in the department of health policy and management at Providence College. She wrote this article for the Washington Post.