The state of America’s fight against Covid-19 is murky. While the pace of vaccinations is promising, some experts, including the CDC director, are warning of “impending doom.”

The good news: More than one in three American adults have received at least one shot of a vaccine and nearly one-fifth are fully vaccinated. On Monday, President Biden said 90% of adults will be eligible for the vaccine by April 19th.

The bad news: New coronavirus cases in the United States continue to rise. Last week, new cases surged by as much as 12 percent.

Variants are thought to be driving the surge. In Pennsylvania, “more than a third of samples taken over the last month from 80 COVID-19 patients had mutations known to make the virus more transmissible or resistant to current vaccines, or both,” according to a researcher quoted in The Philadelphia Inquirer.

“Pandemic fatigue” is also a factor as people drop their guard and become less diligent about mask wearing and social distancing.

Michigan’s 57% increase in new cases – the highest in the country – is representative of America’s one step forward, two steps back conundrum. The state – led by Governor Gretchen Whitmer, a Democrat – recently relaxed Covid-19 restrictions by increasing the capacity of restaurants, sports arenas, gyms, movie theaters, and casinos. Now Covid-19 hospitalizations are up by 47% there.

“[The increase in cases and hospitalizations are a] stark reminder that this virus is still very real,” Whitmer said last week. “It can come roaring back if we drop our guard.”

Meanwhile, air travel is beginning to pick up. CBS News reports that “for 17 days in a row now, the TSA has screened more than 1 million people U.S. airports, marking a significant milestone for the industry.”

CBS adds:

The uptick in fliers comes despite the U.S. Centers for Disease Control and Prevention’s recommendation that even vaccinated Americans postpone all travel plans until more is known about how effective vaccines are against new COVID-19 variants — and whether vaccinated individuals can spread the disease.