U.S. COVID-19 deaths surpass 500,000 as virus variants pose new threats

People walk out from the emergency of a hospital in New York, the United States, Feb. 22, 2021. The United States reached the grim milestone of half a million coronavirus deaths on Monday, according to the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University. (Xinhua/Wang Ying)

WASHINGTON, Feb. 22 (Xinhua) -- The U.S. COVID-19 deaths surpassed the grim milestone of 500,000 on Monday as key indicators of virus transmission in the country have continued to fall, while emerging variants are causing fresh concerns.

As of 06:23 pm EST (2323 GMT) on Monday, 500,172 Americans have died from COVID-19 with the total infections topping 28.1 million, according to a tally by Johns Hopkins University (JHU).

The half-million U.S. fatalities represent more reported COVID-19 deaths than any other countries in the world. More than 111.6 million people have been infected and over 2.47 million have died worldwide, showed the JHU data.

"That's more lives lost to this virus than any other nation on Earth," said U.S. President Joe Biden when he held a moment of silence and a candle-lighting ceremony at the White House in remembrance of the deaths.

"But as we acknowledge the scale of this mass death in America, we remember each person and the life they lived," said Biden, who was joined by First Lady Jill Biden, Vice President Kamala Harris and Second Gentleman Douglas Emhoff.

"We ask you to join us to remember. So we can heal. To find purpose, and the work ahead to show that there is light in the darkness," Biden said.

Earlier in the day, Biden ordered all U.S. flags to be flown at half-staff for five days at all federal buildings and military posts in the United States and abroad.

The first COVID-19 infection in the United States was reported on Jan. 19, 2020 in the state of Washington. One year later, on Jan. 19, 2021, the last full day of Donald Trump's presidency, the U.S. COVID-19 death toll reached 400,000.

The first U.S. fatality occurred in early February in Santa Clara County, California, and it took four months to reach the first 100,000 deaths at the end of May 2020.

"It's terrible. It is historic. We haven't seen anything even close to this for well over a hundred years since the 1918 pandemic of influenza," said Dr. Anthony Fauci, the nation's top infectious disease expert, Sunday on NBC's "Meet the Press" while talking about the staggering numbers.

Fauci said that political divisiveness contributed significantly to the "stunning" U.S. COVID-19 death toll in an interview with Reuters on Monday.

The grime milestone came as key indicators of COVID-19 transmission in the United States continued to fall, but health experts warned the public not to let down guard, as the country saw uptick in coronavirus variants infections.

"We continue to see trends head in the right direction, but cases, hospital admissions, and deaths remain at very high levels," said Rochelle Walensky, director of the U.S. Centers for Disease Control and Prevention (CDC), at the COVID-19 briefing on Monday.

New cases have been declining steadily for five weeks, with the current seven-day average of 66,000 per day down 74 perent from its peak on Jan. 11, according to Walensky.

The seven-day average of new hospital admissions is at 6,500 per day, a 60 percent decline from a peak on Jan. 9, Walensky said. And the seven-day average of deaths is at 1,900, down 39 percent from the prior seven-day average.

"The vaccine rollout is the major reason for the decreasing of new cases, deaths and hospitalizations," Zhang Zuofeng, professor of epidemiology and associate dean for research with the School of Public Health at the University of California, Los Angeles, told Xinhua.

Over 75 million vaccine doses have been distributed across the United States as of Monday, and more than 64 million doses have been administered, the CDC data shows.

Biden's national vaccination campaign aims to administer 100 million doses of two-stage coronavirus vaccines in his first 100 days in office.

The drop of cases, hospitalizations and deaths are encouraging, said Stanley Perlman, professor of microbiology and immunology at the University of Iowa.

"It may mean that we are over the holiday bump," he told Xinhua in an interview.

"It is too early to know if this is a turning point because new, more contagious variants are circulating in the United States," Perlman also noted.

A total of 1,688 infection cases of coronavirus variants have been reported in the United States as of Sunday, according to the CDC.

The vast majority of these cases, 1,661, were caused by the variant known as B.1.1.7, which was originally detected in Britain.

There were 22 cases of a new strain initially discovered in South Africa, called B.1.351, and five cases of the P.1 strain first discovered in Brazil.

Modeling data suggest that B.1.1.7 could become the predominant variant in the United States in March.

"We hope that the vaccine rollout will outweigh the variants spread," Perlman said.

"The vaccines could provide some protection against the variants," said Zhang. "If we can complete mass vaccination to reach general immunity before the variants take hold, the situation could get in control."

"Otherwise, if the vaccine rollout lags behind the spread of variants, and the variants evolve to a pandemic, it will bring huge disaster," Zhang said.

Zhang predicted that based on the current vaccination speed, about 75 percent of the U.S. population will be vaccinated by July or August.

Americans may still need to wear masks in 2022 to protect against the coronavirus even as the United States may reach "a significant degree of normality" by the end of 2021, said Fauci on Sunday, stressing the importance of mitigation measures to fight the pandemic.

An influential coronavirus model has predicted an estimated 589,197 COVID-19 deaths in the United States by June 1.

According to the latest forecast from the Institute for Health Metrics and Evaluation at the University of Washington, the result depends on the vaccine rollout and the spread of variants. A worst-case scenario could see the death toll go as high as 616,341.