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LOS ANGELES - The head of the U.S. Centers for Disease Control and Prevention issued a statement on the one-year anniversary of the COVID-19 pandemic, while acknowledging the heartbreaking toll of a health crisis that has claimed the lives of more than 520,000 Americans.
"One year ago today, the World Health Organization declared COVID-19 a global pandemic. The toll of this disease and the continued loss of life around the world and in our nation is heartbreaking. To so many of you who have felt the pain and loss of a loved one during this pandemic – you have suffered the ultimate loss, and we grieve with you," Dr. Rochelle Walensky, the director of the CDC, said in a statement Thursday.
"After a year of this fight, we are tired, we are lonely, we are impatient. There have been too many missed family gatherings, too many lost milestones and opportunities, too many sacrifices. And still, through it all, there is determination; there are stories of giving and hope, of stamina and perseverance. We are better together, and together, we will endure," Walenksy continued.
Walensky said that vaccinations distributed to millions of people every day gives her hope of beating back the pandemic that has claimed the lives of so many people in the world.
The CDC released its first evidence-based guidance for fully vaccinated people last week.
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"These new recommendations are a first step in our process of returning to everyday activities – safely spending time with family and friends, hugging our grandparents and grandchildren, and celebrating birthdays and holidays," Walenksy said in a statement.
As of Wednesday, there had been over 29 million COVID-19 cases in the United States, and the coronavirus had killed over 529,000 Americans, according to data by Johns Hopkins University.
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"These are grandparents, parents and children. They are siblings, friends, and neighbors. They are our loved ones and our community. We join together to grieve these losses and intensify our efforts so they were not in vain," Walensky wrote.
On Monday, Walensky said the coming two months are critical for the nation to prevent a possible next wave of COVID-19.
"There is so much that's critical riding on the next two months," Walensky said, speaking at a National League of Cities virtual conference on Monday. "How quickly we will vaccinate versus whether we will have another surge really relies on what happens in March and April.
"The race to vaccinate the majority of Americans comes as medical experts continue to sound the alarm on the possibility of a coming COVID-19 surge involving one of the many viral mutations that have been identified across the globe.
Scientists widely agree that the U.S. simply doesn’t have enough of a handle on the variants to roll back public health measures and is at risk of fumbling yet another phase of the pandemic after letting the virus rage through the country over the last year.
"Now is not the time to fully open up," said Karthik Gangavarapu, a researcher at Scripps Research Institute whose team works closely with San Diego health officials to watch for mutant versions of the coronavirus. "We need to still be vigilant."
RELATED: CDC: Fully-vaccinated people can gather without masks, should still cover face in public
In March 2020, the virus began to spread widely outside of Washington state — where the first coronavirus death was reported.
As cases continued to rise in Washington, public officials faced pressure to take more aggressive steps, including closing schools and canceling large events. Some individual schools and businesses closed temporarily. Meanwhile, schools considered whether to plan for online classes in the event of prolonged shutdowns.
In New York state, with a large surge of cases, the health department accelerated regulations to get nursing students certified to work more quickly.
Then-President Donald Trump issued an emergency declaration and said he was giving the U.S. health secretary authority to waive federal regulations and laws to give doctors and hospitals "flexibility" in treating patients. Trump also announced a government partnership with major businesses to set up drive-thru testing centers and a website to help people who think they might have the virus.
"This is going to be a very, very painful two weeks," Trump said in mid-March during a coronavirus task force briefing from the White House.
RELATED: CDC director says next 2 months critical in stopping another COVID-19 surge
Dr. Deborah Birx, a then-member of the Trump White House coronavirus task force, discussed models that showed that projected deaths in the U.S. could range between 100,000 and 240,000 with mitigation efforts. Without mitigation efforts, the projected death count in the U.S. was between 1.5 and 2.2 million.
At the time, few could foresee the long road ahead or the many ways in which they would suffer. Over the course of the next 12 months, millions of people would die or become so sick they required hospitalization, and national economies would be devastated by public lockdowns and record unemployment.
Throughout the summer, the American COVID-19 death toll climbed steadily, reaching 175,000 by the end of August. By Sept. 22, more than 200,000 Americans had died.
The U.S. also faced a brutal surge in the winter months, climbing steadily in October and November. On Nov. 4, more than 100,000 COVID-19 cases were being reported in a single day — one of many grim milestones throughout the year.
By the end of 2020, more than 336,000 Americans had died from the virus. At the end of February, half a million lives had been lost.
A year in, Walensky exhorted Americans to stand firm in their compliance with public health measures, and she looked to the future.
"This pandemic will end. And, our public health work will continue. Through the near-blinding spotlight of this crisis, we now clearly see what we should have addressed before– the long-standing inequities that prevent us from achieving optimal health for all. We see the impact of years of neglect of our public health infrastructure. We see the critical need for data that move faster than disease, to prevent rather than react," Walensky said.
"To move past this pandemic, we must resolutely face these challenges head on and fully embrace the innovations, the new partnerships, and the resilience of our communities that have emerged from this crisis. It is the only way we can turn tragedy and sorrow into lasting progress and improved health for all," Walensky continued.
Kelly Hayes and Austin Williams contributed to this story.