Cody Pickens for TIME

On a hyperconnected planet rife with hyperinfectious diseases, experts warn we aren't ready to keep America--and the world--safe from the next pandemic

Across China, the virus that could spark the next pandemic is already circulating. It’s a bird flu called H7N9, and true to its name, it mostly infects poultry. Lately, however, it’s started jumping from chickens to humans more readily–bad news, because the virus is a killer. During a recent spike, 88% of people infected got pneumonia, three-quarters ended up in intensive care with severe respiratory problems, and 41% died.

What H7N9 can’t do–yet–is spread easily from person to person, but experts know that could change. The longer the virus spends in humans, the better the chance that it might mutate to become more contagious–and once that happens, it’s only a matter of time before it hops a plane out of China and onto foreign soil, where it could spread through the air like wildfire.

From Ebola in West Africa to Zika in South America to MERS in the Middle East, dangerous outbreaks are on the rise around the world. The number of new diseases per decade has increased nearly fourfold over the past 60 years, and since 1980, the number of outbreaks per year has more than tripled.

Some recent outbreaks registered in the U.S. as no more than a blip in the news, while others, like Ebola, triggered an intense but temporary panic. And while a mutant bug that moves from chickens in China to humans in cities around the world may seem like something out of a Hollywood script, the danger the world faces from H7N9–and countless other pathogens with the potential to cause enormous harm–isn’t science fiction. Rather, it’s the highly plausible nightmare scenario that should be keeping the President up at night.

The U.S. Centers for Disease Control and Prevention (CDC) ranks H7N9 as the flu strain with the greatest potential to cause a pandemic–an infectious-disease outbreak that goes global. If a more contagious H7N9 were to be anywhere near as deadly as it is now, the death toll could be in the tens of millions.

“We are sitting on something big with H7N9,” says Michael Osterholm, the director of the Center for Infectious Disease Research and Policy at the University of Minnesota and a co-author of the new book Deadliest Enemy: Our War Against Killer Germs. “Any one of these cases could trigger something big. By then it’d be way too late.”

Too late because even as the scientific and international communities have begun to take the threat of pandemics more seriously, global health experts–including Bill Gates, World Health Organization director Dr. Margaret Chan and former CDC director Dr. Tom Frieden, to name just a few–warn that nowhere near enough is being done to prepare, leaving the U.S. scarily exposed. That’s because the system for responding to infectious disease is broken. So broken that it recently prompted Gates and his wife Melinda to put their weight behind a major public-private initiative called the Coalition for Epidemic Preparedness Innovations (CEPI). The Gates Foundation alone will devote $100 million over the next five years to CEPI, which will help speed the development of vaccines against known diseases, like MERS, while also investing in next-generation technologies that can counter future threats.

Since President Donald Trump took office, key government positions remain unfilled, including a new director for the CDC. The budget the President proposed in March would have slashed critical funding at the Department of Health and Human Services (HHS) by $15.1 billion, including deep cuts to the National Institutes of Health (NIH), which underwrites more infectious-disease research than any other agency in the world. The budget for the State Department and foreign aid–which power vital efforts to stop diseases overseas, where they usually originate–was set to be cut by 28%. Although a bipartisan congressional spending deal reached on April 30 blocked many of those cuts, the signals Trump has sent are worrying. “It’s early days, but if we compare to what we’ve seen in the past, it raises some alarm bells,” says Jeremy Youde, a global health expert at ANU College of Asia and the Pacific.

The consequences of a major pandemic would be world-changing. The 1918 flu pandemic killed 50 million to 100 million people–at the top end, more than the combined total casualties of World Wars I and II–and for a slew of reasons, humans are arguably more vulnerable today than they were 100 years ago. First of all, there are simply more of us. The number of people on the planet has doubled in the past 50 years, which means more humans to get infected and to infect others, especially in densely populated cities. Because people no longer stay in one place–nearly 4 billion trips were taken by air last year–neither do diseases. An infection in all but the most remote corner of the world can make its way to a major city in a day or less.

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Climate change also plays a role as warmer temperatures expand the range of disease-carrying animals and insects we’re exposed to, like the Aedes aegypti mosquitoes that transmit Zika. And if nature isn’t bloody-minded enough, genetic-engineering tools have made it easier for terrorist groups or lone madmen to unleash custom-designed killer germs.

In the case of a new pandemic, modern medicine should provide some protection. But experts say it’s more likely that we’ll be caught without a vaccine to prevent it or a drug ready to treat it. That’s true even with many known viruses. When the last Ebola outbreak exploded, in 2014, eventually killing more than 11,000 people, the virus wasn’t a mystery to scientists; it was discovered in 1976. But even though it had been killing people on and off for decades, there were no drugs or vaccines approved to fight it–and there still aren’t today, chiefly because there’s little incentive for pharmaceutical companies to bring them to market.

There are troubling economic implications as well. The 2003 SARS epidemic, which killed fewer than 800 people, cost the global economy $54 billion, much of it in lost trade, transportation disruption and health care costs. The World Bank estimates that the toll from a severe flu pandemic could hit $4 trillion.

One saving grace is that the scientific understanding of that risk is better than ever. Research groups are working feverishly to predict the next pandemic before it even happens. They’re cataloging threats and employing next-generation genetic-sequencing tools to speed the discovery of new or mysterious viruses. They’re helping identify and track outbreaks as they happen.

But microbes evolve about 40 million times as fast as humans do, and we are losing ground. “Of all the things that can kill millions of people in very short order,” says Dr. Ashish Jha, director of the Harvard Global Health Institute, “the one that is most likely to occur over the next 10 years is a pandemic.” The question is how policy–and the government dollars that back it–can catch up with the science and keep the world safe.

Doctors couldn’t tell what was wrong with Joshua Osborn, but they knew they were running out of time to save his life. Since the 14-year-old had returned to Wisconsin from a family trip to Puerto Rico, he’d suffered severe headaches and dangerously high fevers. Over the course of many months, each of the three dozen infectious diseases he was screened for–including West Nile virus, tuberculosis, Epstein-Barr and more–came up negative. Joshua was dying, but no one knew why.

His doctor, desperate, shipped vials of the boy’s spinal fluid and blood to a team of scientists in San Francisco–a specialty lab run by Dr. Charles Chiu at the University of California, San Francisco (UCSF). Chiu is an undisputed leader in the field of genomic diagnosis–the science of using genetic sequences to identify pathogens–and he was Joshua’s last hope.

Joshua’s mystery was extreme in its consequences but not in its details. Up to 25% of pneumonia cases and up to 70% of meningitis and encephalitis cases are caused by unknown pathogens. Doctors are usually able to narrow the cause enough to come up with an effective treatment, but not always. That’s where genomic diagnosis, which involves sequencing all the genetic data in a patient sample in an effort to find all hidden pathogens, will be game-changing.

At the UCSF-Abbott Viral Diagnostics and Discovery Center, Chiu and his team can map blood samples against more than 8 million distinct DNA sequences to see if they match any of the known pathogens on file. For Joshua’s case, they had a suspect pegged in just 97 minutes: something called Leptospira santarosai, a rare pathogen found in parts of the Caribbean, including Puerto Rico.

“Back in the 1980s, it would take two years to do that kind of computational work,” Chiu says. “We’ve developed a program that can analyze 10 million reads in under 30 minutes.” On the strength of Chiu’s diagnosis, Joshua was treated with basic antibiotics, and four weeks later, he was healthy again.

The genetic sequence of a pathogen is a virtually fail-safe fingerprint, which is why tests like Chiu’s can be so effective in diagnosing a single person’s mystery illness. It’s the diagnostic equivalent of fishing for germs with a huge net, instead of a single line. Genetic sequencing is especially valuable when an unknown pathogen starts killing people in droves.

In 2009, a cluster of people living in the southwestern corner of the Democratic Republic of Congo came down with a hemorrhagic fever and symptoms that included bleeding from their mucous membranes. Scientists in the field tested them for a range of pathogens known to cause similar symptoms, but it wasn’t until Chiu’s lab analyzed all the genetic information available that the culprit was identified: an entirely new pathogen from the family of viruses that cause rabies, among other things. “It’s a major transition from what we have been able to do in the past,” says John Hackett, divisional vice president of applied research and technology at Abbott, a major global health care company that helps fund Chiu’s lab.

Scientists are already using these tools on active outbreaks, tracking the spread of a disease through changes in its genetic sequences. In the 2014 Ebola outbreak, a geneticist from MIT and Harvard, Dr. Pardis Sabeti, was able to determine via genomic sequencing that the virus was spreading primarily from human to human–not from animal to human, as experts had thought. That simple discovery dramatically altered how experts were fighting the spread of the disease in the field.

That kind of information can mean the difference between an outbreak that kills hundreds instead of millions. The hope is that scientists will be able to use genetic information to predict how a pathogen will behave–before a single person ever falls ill. “That’s the holy grail,” says Dr. Ian Lipkin, director of the Center for Infection and Immunity at Columbia University. Before that can happen, however, scientists need to collect all those genetic fingerprints in the first place.

Nearly all the new infectious diseases that scientists know about today originate in animals, and so will the emerging diseases of tomorrow. HIV began in chimpanzees, SARS in Chinese horseshoe bats, influenza in aquatic birds. At some point the animal pathogens jump the species barrier to humans, an event disease experts call a spillover. Spillovers have always occurred, but the rapid environmental change wreaked by humans in recent years has accelerated the spread.

But what if there were a way to prevent those spillovers from ever occurring? That’s the aim of PREDICT, an ambitious program designed to rapidly detect and respond to emerging pathogens. Since it was launched in 2009, PREDICT, which is funded by the U.S. Agency for International Development (USAID), has helped discover nearly 1,000 new viruses in animals and humans.

“Outbreaks are like fires,” says Dr. Eddy Rubin, chief science officer at Metabiota, a San Francisco–based startup that uses big data to analyze outbreaks and is a partner of PREDICT. “If you’re able to understand where there is a greater likelihood of their occurring and detect them early on, you can shift the impact.”

Another piece of the pandemic-prevention puzzle is the Global Virome Project, an ambitious strategy to identify, characterize and sequence the nearly half-million viruses that have the potential to spill over. The scientists behind the project estimate that it would cost $3.4 billion to complete. It’s a huge amount of money in the shoestring world of animal health–PREDICT, by comparison, is funded at $100 million–but its proponents believe that the project would easily pay for itself many times over if it could successfully stop a single pandemic.

The Global Virome Project, which has been championed by leading infectious-disease experts around the world, is still almost entirely aspirational–though so was the Human Genome Project when it was first proposed by academic biologists years before its formal government launch. But if deep cuts to USAID’s budget are made, there may not be sustained funding for the current work being done in the field–let alone something even more ambitious. “This ties into global security,” says Jon Epstein, a vice president at EcoHealth Alliance, another PREDICT partner. “Hopefully they’ll see the value in that.”

Jung Yeon-Je—AFP/Getty Images

For all the advances in finding dangerous pathogens, the simple truth is that neither the world as a whole nor the U.S. in particular is at all prepared to handle a major infectious-disease pandemic–and a significant reason for that is a failure to invest in things now that can keep us safe later. The middle of the 20th century was a golden age for vaccines as scientific heroes like Dr. Jonas Salk developed drugs to protect against life-threatening diseases like polio. Yet today, while the worldwide pharmaceutical market is worth more than $1 trillion, the market for vaccines makes up at most 3% of it.

That’s why the Gates Foundation, Britain’s Wellcome Trust charity and several governments launched CEPI this year. Beyond funding research to develop vaccines against existing threats, the CEPI fund–which aims to raise and spend $1 billion over the next five years–will also support research into entirely new ways to develop vaccines.

No disease better illustrates the need for a next-gen vaccine than influenza. “We need to do better with flu vaccine,” says Dr. Anthony Fauci, director of the NIH National Institute of Allergy and Infectious Diseases. A healthy market exists for the seasonal-flu vaccine, but because the influenza virus constantly mutates, a new version has to be made each year, a process that takes months. That lag could be deadly during a severe influenza pandemic. Humans have little to no immune protection against new flu strains, which then spread rapidly around the world and–sometimes–cause severe disease. And though the flu usually isn’t deadly for otherwise healthy people, it can be, as the 1918 pandemic showed. While flu vaccines didn’t exist in 1918, they did in 2009, when a new flu strain jumped from pigs to people and ultimately killed an estimated 203,000 people around the world, a majority of them under the age of 65. Efforts were made to fast-track a vaccine, but the first doses weren’t available for 26 weeks, and it would have taken a year to produce vaccines for every American.

Since it can require years of testing and well over $1 billion to successfully develop a single vaccine against a single pathogen, drug companies have increasingly shied away from the business. “There’s just no incentive for any company to make pandemic vaccine to store on shelves,” says Dr. Trevor Mundel, president of the global health division at the Bill and Melinda Gates Foundation.

That’s why most infectious-disease experts aren’t hanging their hopes solely on new treatments or vaccines. After all, that’s not what ultimately contained the most recent lethal outbreak of Ebola.

It chiefly fell to health workers on the ground and to Frieden, director of the CDC for eight years under President Obama. And on no day did that effort come closer to failure than on July 23, 2014. That was the day Frieden received news that Ebola had arrived in the Nigerian megacity of Lagos. The virus had been killing people for months in Guinea, Liberia and Sierra Leone, but Ebola in Lagos–the biggest city on the African continent, with a metro population of 21 million–represented a threat of an entirely different magnitude.

“If it got out of control in Lagos, it could spread through Nigeria and the rest of Africa,” says Frieden. “It could still be going on today.”

But it isn’t, thanks largely to the herculean efforts of thousands of expert health workers–U.S. staff from the CDC and Nigerian officials who had been trained in the international effort to stop polio–who were quickly diverted to fight Ebola.

This is why Frieden, Gates and others are so bullish about investing in science and foreign aid. Without aid, Nigeria would not have been able to stem the spread of Ebola. And without the next-generation science that helped track the outbreak, far more people would have died. “It’s very important that this kind of work continues,” says Frieden, “or America is going to be less safe.”

Make no mistake: for all our high-tech isolation units, top-tier doctors and world-class scientists, the U.S. health care system is not ready for the stresses of a major pandemic. As the infectious-disease expert Osterholm notes, a pandemic is not like other natural disasters, which tend to be confined to a single location or region. Disease can strike everywhere at once. In the event of a pandemic, even the best hospitals could rapidly run out of beds and mechanical ventilators.

The U.S. does have a national strategy for pandemics, and there have been welcome steps taken since the bioterrorism fears that followed 9/11. In February, the military think tank DARPA launched a program aimed at producing effective medicines within 60 days of the identification of a new, pandemic-causing pathogen. But the country hasn’t been truly tested yet.

Melissa Harvey, who heads the division of national health care preparedness programs at HHS, is in charge of helping U.S. hospitals get ready for the next big threat. She notes that while hospitals were able to handle a handful of sick people during Ebola, a truly major crisis would be a different story. “In a situation like the 1918 pandemic, the expectation is that the resources are not going to be there for everyone.”

If you look at the numbers, it’s clear that right now the U.S. government doesn’t spend in a way that says fighting pandemics is a consistent national priority. Instead, money gets issued on a disease-by-disease basis, often after a crisis has started. During Ebola, for instance, Congress appropriated more than $5 billion in much-needed emergency spending–but it did so nearly five months after international health groups had called it a crisis.

The drawbacks of this scattershot way of investing in pandemic response became even clearer during Zika, when it took nearly nine months for Congress to finally allocate $1.1 billion to fight a disease that had already begun spreading in the U.S. Even then, Congress required that some of that come from existing Ebola funding that had been going to pandemic preparation. “We literally had to rob Peter to pay Paul,” says Ron Klain, who served as Ebola czar during the Obama Administration.

Experts say the U.S. needs sustained funding for pandemic preparedness that extends out for years. That kind of money could help push vaccine candidates across the valley of death from R&D to commercialization as well as fund entirely new vaccine technologies. It could also ensure a steady supply of doctors and nurses trained to deal with pandemics at home, support U.S. efforts to build defenses abroad and provide a fund that could be easily tapped in the event of an outbreak.

Will Trump do that? His proposed budget from March contained some encouraging signs, including a pledge to create a new federal emergency-response fund for public-health threats as well as commitments to continue funding international programs on HIV/AIDS. But the details of the emergency fund are vague, and Trump’s pledge to increase the defense budget by $54 billion would have to be offset in part by slashing spending on health, including the NIH, which would have seen its budget cut by a fifth. Some research groups, like the NIH’s Fogarty International Center, which works on emerging-disease research overseas, would have been eliminated altogether. Proposed cuts to foreign aid and the State Department–which could eventually hit pandemic-prevention programs like PREDICT–would also be felt when the next pandemic hits.

Trump’s budget proposal is just that–Congress holds the ultimate power over government spending. But in the event of a pandemic, it is the President who must lead the country.

During Ebola, Trump issued a series of tweets that have sown doubts about how he would handle a true health crisis. One called for stopping American health care workers who had been infected with Ebola from returning to the U.S. “The U.S. cannot allow EBOLA infected people back. People that go to far away places to help out are great–but must suffer the consequences!” he wrote. Another tweet warned, without evidence, that “Ebola is much easier to transmit than the CDC and government representatives are admitting.” In the past he has raised doubts about the safety of vaccines, a long-discredited belief that is nonetheless shared by an increasing number of Americans, leading to a resurgence of preventable childhood diseases like measles.

Trump’s habit of making wild claims on Twitter could be especially dangerous in the event of a pandemic, when public confidence in government is critical to public safety. “The emerging climate of fake news and alternative facts leaves us worse off than ever before,” says Arthur Caplan, a bioethicist at New York University. “I am very worried, because I’m certain that we will get an outbreak.”

On the campaign trail Trump said repeatedly that he would make America safe. But a multibillion-dollar wall at the border won’t keep out disease, and cutting aid to health systems overseas is akin to slashing the CIA’s budget in a time of war. If Trump is serious about protecting Americans, global health critics contend, he must embrace the soft power of pandemic preparation.

In a memorable 2015 TED talk, Bill Gates told his audience that “when I was a kid, the disaster we worried about most was a nuclear war.” But today, he said, “if anything kills over 10 million people in the next few decades, it’s most likely to be a highly infectious virus, rather than a war. Not missiles, but microbes.”