As European countries continue to drop pandemic restrictions, many are now seeing increases in new Covid-19 cases, sparking concerns about whether a new wave may be coming—and whether the United States could see a similar trend in the coming weeks.

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Covid-19 cases are on the rise in Europe

Almost half of all European countries have reported Covid-19 case increases over the past week, according to an NBC News analysis of data from Johns Hopkins University.

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In particular, several countries have seen double-digit percentage increases in their weekly Covid-19 case numbers. For example, Finland saw its weekly Covid-19 case numbers increase 84% to 62,500, while the United Kingdom saw a 31% increase over the past week to 414,480 cases. Other countries that saw significant increases in new cases include Switzerland, France, Germany, and Italy.

The next wave in Europe has begun pic.twitter.com/2qm4JzOqit

— Eric Topol (@EricTopol) March 12, 2022

In addition, data from Our World in Data indicates that Covid-19 hospitalizations are also increasing in several European countries, including Ireland, the United Kingdom, and the Netherlands.

Among countries that make their data available, some show rising hospital admissionshttps://t.co/lwT6Owyvjs pic.twitter.com/oNwxsS8rNx

— Eric Topol (@EricTopol) March 12, 2022

According to Eric Topol, founder and director of the Scripps Research Translational Institute, several factors are likely driving this uptick in European cases, including relaxed Covid-19 restrictions, the spread of omicron subvariant BA.2, and waning vaccine protection.

For example, in England, Prime Minister Boris Johnson lifted all domestic Covid-19 restrictions, including the requirement to self-isolate after testing positive. France also recently lifted many of its pandemic restrictions, including proof of vaccination requirements for restaurants, movie theaters, and other public spaces.

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However, Topol noted "[t]here's no clear or consistent pattern to determine which (or all) of these factors are driving [the increase in Covid-19 cases in Europe" and that "no new variants have been implicated."

What does this mean for America?

According to NBC News, disease experts are keeping a close eye on Covid-19 trends in Europe in case a similar increase in new cases arises in the United States in the next few weeks.

"There is certainly a risk that the U.S. could face another surge in cases, as Europe is seeing," said Gavin Yamey, a professor of global health and public policy at Duke University. "We have lower rates of vaccination and booster coverage than many European nations, so a surge here could translate into rising hospitalizations."

Currently, Covid-19 case rates in the United States have been declining, with CDC data showing an average of 34,805 new daily cases—the lowest figure since July 2021. However, only 44.3% of the U.S. population has received a booster dose, meaning that many remain vulnerable to coronavirus infection as their immunity wanes.

At the same time, CDC's wastewater sampling conducted between Feb. 24 through March 10 indicates an uptick in Covid-19 cases. Out of 401 active wastewater sampling sites, 145 revealed an increase of 10% or more in coronavirus wastewater levels, 48 revealed an increase of anywhere from 100% to 999%, and 62 showed an increase of 1000% or more.

In an interview with CNBC, former FDA Commissioner Scott Gottlieb said the United States "will probably see a bump up of infections as we lift mitigations [and] as [the omicron subvariant] starts to spread and become more prevalent."

However, he added that he doesn't think that there's "going to be another major surge of infections," but instead "an uptick before you start to see continued declines heading into the spring and the summer."

Even if another Covid-19 wave does not manifest in the United States, experts say that now is the time to be vigilant and begin preparing for potential future waves or new variants. "The U.S. certainly needs to take note and consider the impact of yet another more transmissible variant," said Lawrence Young, a virologist at the University of Warwick in England.

According to Yamey, the U.S. government should work to expand vaccination and booster coverage and ensure that high-quality masks and rapid tests are widely available if cases begin rising again. "We should take the opportunity provided by the current lull to prepare for a possible further wave or variant of concern," he said.

"At this point, a new wave [of] Covid-19 anywhere ought to be viewed as a potential new wave worldwide," said Ogbonnaya Omenka, an assistant professor and director of diversity at the Butler University College of Pharmacy and Health Science. "This is a more beneficial approach regardless of the outcome," he added. (Ortiz, NBC News, 3/14; Stanton, USA Today, 3/14; Owens, Axios, 3/14; Carbajal, Becker's Hospital Review, 3/14; Dress, The Hill, 3/15)