Editor’s Note: Megan Ranney, MD, MPH, is an associate professor of emergency medicine and associate dean of the School of Public Health at Brown University. The opinions expressed in this commentary are their own. View more opinion on CNN.

CNN  — 

Many of us started the summer fully vaccinated and ready to celebrate. I booked tickets for work and family trips, left my mask at home when seeing friends, and took a deep sigh of relief that the worst seemed to be behind us.

Megan Ranney

But now Covid-19 cases are rising at my hospital. My colleagues and I are worried about kids going back to school while so many are ineligible for vaccination. Many businesses are telling their workers to stay home a bit longer. Daily infection rates are more than three times higher than they were last Labor Day in the US – and in the coming days and weeks, we could be met with still higher infection rates as Covid cases that were picked up on Labor Day travels are detected.

It’s hard not to feel tricked. Is it 2020 all over again? Worse yet, is this what our future looks like?

From a medical perspective, the answers are both yes and no. Here’s why.

The bad news is that some things haven’t changed. The good news is that despite the sense of déjà vu, this moment is profoundly different from last summer.

The world still suffers from an inexplicable deficit of basic knowledge about this virus and its variants. The Delta variant is clearly more transmissible, but somehow, six months after its identification, we still don’t know whether it’s inherently more dangerous, particularly for children. The US Centers for Disease Control and Prevention (CDC) is not consistently tracking the many so-called “breakthrough” infections that don’t require hospitalization, so we are left guessing how well the vaccines protect from mild and asymptomatic infection. And we have no reliable dataset on school transmission. This lack of data makes it difficult to provide airtight recommendations to the public as we embark on a new school year.

This moment also feels like last year because of the sense of overwhelm and exhaustion in our hospitals and schools. My health care colleagues in southern states are in a particularly bad spot; some of them are facing hospitalization numbers that dwarf the first three waves of this disease. We barely had a chance to catch our breath before another wave hit this summer. We are making crisis care decisions, just as we did last winter. Parents and school staff are also back in a world of revolving quarantines and fear.

And it feels like last year when our biggest fights – about masks, unproven treatments, vaccinations and testing – are about the politics rather than about the science.

Now, the good news.

The most important thing we have now that we didn’t have in 2020 is, of course, the vaccines. They work incredibly well against severe illness. Vaccines decrease your risk of not just hospitalization and death but also seem to decrease your chance of developing “Long COVID”.

Granted, not enough of us – in or outside the US – are vaccinated. Our younger children still can’t get their shots. But nonetheless, the sheer speed of vaccination – the fact that literally billions of people across the globe have had a first shot – makes this moment decidedly different. And things will continue to get better, as more people across the world have a chance to be immunized.

Another thing that we have going for us is that even in a Delta-dominant world, basic non-pharmaceutical interventions – including masking up, and improving ventilation – reduce transmission and illness. Given this clear science, it is inexcusable that we lack clear recommendations for schools and workplaces, while we know what to do to stop the spread.

Which leads to the biggest difference between last year and today: We are in a place of shades of gray, not blacks and whites.

We will likely never go back to full shutdowns, but we must reset our expectations. This virus is never going to fully disappear. And just as 9/11 changed us forever, this pandemic will, too. The statements that we were “back to normal” or that “this will all be over” were, and still are, political talking points. Our world is never going back to pre-Covid “normal.” The sooner we accept that, the sooner we can move forward.

So let me offer hope and a road map, to help move us from this moment to the next:

If you are fully vaccinated, celebrate. I can’t say it strongly enough: Your world is different from what it was in 2020. Yes, breakthrough infections are possible. But for most of us who are fully vaccinated, those infections will be milder. For those who are immunocompromised, or living with an unvaccinated person, you should take a little extra caution – but you do have a modicum of protection that did not exist last year. For this, give thanks.

No matter who you are or where you are, take a minute to think about the basics of air movement and filtration. Our grandparents used to open the windows to clear out the germs. It’s time for us to do the same. When you’re in a building, make sure the HVAC is turned on. When you can, sit near a window. If you are in charge, buy or make air filters. When you can’t control any of the rest of it, wear a good mask if the virus is surging.

If you have political power, advocate for science. To move forward, we need good data and good guidelines. Everyone from the CDC to our local public health departments to our school departments and our hospitals needs to collect and share reliable data with the American public. These facts can help us overcome the uneven guidance, the fictions and the disinformation that so many fell prey to in the past year and still now. Myths spread when truth is unknown.

Finally, expect that some of the official guidelines will continue to change as the virus and what the science tells us about this virus changes.

Most of us grew up in an era of tremendous freedom from disease. Over the course of the 20th century, thanks to vaccines and sanitation, we escaped the daily fear of polio, hookworm, smallpox, measles and more that plagued earlier generations. American physicians watched childhood death melt away; in just the last 30 years, we have entirely changed the way we evaluate and treat young children with fevers. These successes made us feel invincible.

It is therefore scary and frustrating to know that the microscopic SARS-CoV-2 organism can bring our world to its knees, particularly when we thought we had conquered it. We hadn’t, and haven’t. It’s exhausting to be back in this era of constant decision-making. The mental gymnastics required lead to fatigue and resentment of the world we live in after such an isolating year.

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    Perhaps, then, here is the biggest takeaway from this moment – to be reminded of the bigger picture. Science matters. Community matters. And we are not the masters of the universe, after all.

    If there was ever a moment for a serenity prayer, this is it. “God grant me the serenity to accept the things I cannot change, the courage to change the things I can, and the wisdom to know the difference.” As we enter this next phase of the pandemic, this is what we need most: Patience. Hope. And a sense of humility. We can and will keep moving forward. It’s just going to be different.