After more than two years of Covid-19, plenty of people are lowering their guards. But the pandemic isn't over yet — and, Bill Gates warns, the worst might still be ahead.

"We're still at risk of this pandemic generating a variant that would be even more transmissive and even more fatal," the billionaire Microsoft co-founder and public health advocate told the Financial Times on Sunday. "It's not likely, I don't want to be a voice of doom and gloom, but it's way above a 5% risk that this pandemic, we haven't even seen the worst of it."

New Covid cases, powered by the BA.2 subvariant of Covid's omicron strain, are currently growing across the U.S.: The country's seven-day average of daily new U.S. cases is up to 54,429 as of Sunday, according to Johns Hopkins University data. That's a 9% increase over the week prior, with cases growing in 39 states over that time frame.

But Covid-related deaths are declining, leading White House Covid czar Dr. Ashish Jha to say last month that he's "not overly concerned right now" about BA.2. Rather, its spread is more a reminder that Covid is still lurking — and as Gates notes, the virus could potentially mutate again, resulting in a strain of greater concern.

For Gates, one lesson from the Covid pandemic so far is that preemptive planning and protective measures could help the world better manage future pandemics. It's the core concept of his upcoming book, "How to Prevent the Next Pandemic," set to publish later this year.

One proposal, he says, is for the World Health Organization to launch a global surveillance team, consisting of experts who can quickly spot new health threats around the world and rapidly coordinate with global governments to prevent future illnesses from growing into pandemics.

Gates, who has labeled his proposed task force the "Global Epidemic Response and Mobilization" (GERM) initiative, told the Financial Times that the idea would require significant financial investment from WHO and its member countries in order to create a global team of experts, including epidemiologists and virologists, and give them the tools they need to proactively identify and contain future outbreaks. 

It's a plan that Gates previously floated at the 2022 TED conference in April, where he noted that WHO would likely need to spend more than $1 billion per year on such a global response team. That's costly, but the cost of another pandemic could be far greater.

The International Monetary Fund (IMF) has estimated that the Covid pandemic will cost the global economy over $12.5 trillion by 2024. Meanwhile, more than 6.2 million people are believed to have died globally from the coronavirus, according to WHO, and Gates has repeatedly said in recent years that the world was not properly prepared for this pandemic.

"It seems wild to me that we could fail to look at this tragedy and not, on behalf of the citizens of the world, make these investments," Gates told the Financial Times on Sunday. The line echoed a comment he made at the TED conference in April: "We need to spend billions in order to save trillions."

Between the proposed GERM team and other suggestions from his upcoming book — including fighting back against misinformation and making vaccines more accessible globallyGates has said that his goal for 2022 is "making sure that Covid-19 is the last pandemic." 

And, while he cautions against becoming complacent against Covid's ongoing risks, the billionaire has also expressed optimism that the coronavirus will be more manageable by this summer — saying in January that, ideally, most Americans will eventually be able to treat Covid like the "seasonal flu."

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