One of the hostages was released shortly after 5 p.m. and FBI crisis negotiators continued to communicate with the man in the synagogue Saturday night.

John Floyd, board chair of CAIR Houston and longtime legal counsel for Siddiqui’s brother, said in a statement that his client is not responsible for the situation, is not near Dallas-Fort Worth and that hostage taker has nothing to do with Siddiqui.

The hostages, all of whom were adults, were not physically harmed and did not require medical attention, officials said. “Prayers answered. All hostages are out alive and safe,” Texas Gov. Greg Abbott said in a tweet.

Three senior law enforcement officials briefed on the situation said the man told authorities he wanted the release of Aafia Siddiqui from federal prison. They also said the hostage taker had the rabbi in Colleyville call a rabbi in New York City to say he was being held hostage and that the man wanted his “sister” Siddiqui freed.

New York City Police Department counter-terrorism teams were seen Saturday at the synagogue connected to the New York rabbi who received the call.

A spokesman for Britain's Foreign, Commonwealth and Development Office said in a statement Sunday: “We are aware of the death of a British man in Texas and are in contact with the local authorities.” He did not say whether he was referring to suspect.

“We want the assailant to know that his actions are wicked and directly undermine those of us who are seeking justice for Dr. Aafia,” Floyd said in a statement.

It was unclear how many people were in the synagogue when police received the first disturbance call Saturday morning. On a Facebook livestream of the congregation’s Shabbat morning service, a man could be heard speaking, at times cursing and sounding angry.

Miller, the Colleyville police chief, said officials began receiving reports that a “gunman” had entered the synagogue and had taken four hostages. Local authorities responded and evacuated nearby homes.

DeSarno, the FBI special agent in charge, said hostage negotiators had contact for long periods of time with the man, and credited their work, as well as that of the nearly 200 state, federal and local law enforcement officers, with the resolution.

Virginia, descended on Colleyville as the situation unfolded. Miller said Saturday night that the rabbi of the congregation is a close friend and that the situation was very personal. He added that he saw hope in how the community came together during the crisis.

Late Saturday night, Biden thanked those who worked to bring the four hostages home to their families.

Congregation Beth Israel, affiliated with Judaism's Reform movement, began in 1998 as a chavurah or a small group of Jewish people who gather for prayer services, according to its website. The group officially established a synagogue in Colleyville in July 1999, and began services at its current location in 2005.

And that was just the beginning. Here are five significant ways that America was changed by 9/11.

When President George W. Bush addressed Congress and the nation on September 20, 2001, he made a case for a new kind of military response; not a targeted air strike on a single training facility or weapons bunker, but a wide-ranging global War on Terror.

When American troops invaded Afghanistan less than a month after September 11th, they were launching what became the longest sustained military campaign in U.S. history. The fight in Afghanistan had support from the American people and the backing of NATO allies to dismantle al Qaeda, crush the Taliban and kill Osama bin Laden, the murderous mastermind of the 9/11 attacks.

in 2015 and in 2016, that figure surpassed 2001 numbers, reaching 127.

One of the most disturbing aspects of the 9/11 attacks was that 19 al Qaeda hijackers were not only able to board commercial aircraft with crude weapons but also force their way into the cockpit. It was clear that 9/11 was both a failure of America’s intelligence apparatus to identify the attackers and a failure of airport security systems to stop them. Even though there had already been a handful of high-profile hijackings and bombings of commercial planes, including the tragic 1988 bombing of Pan Am Flight 103 over Lockerbie, Scotland, security was not a high priority for airlines before 9/11, says Jeffrey Price, a professor of aviation and aerospace science at Metropolitan State University and a noted aviation security expert.

 Yet the ever-present shadow of 9/11, Jenkins says, kept U.S. troops on the ground in Afghanistan and elsewhere for nearly 20 years.

In addition to an army of blue-uniformed screeners, TSA introduced U.S. travelers to extensive new security protocols. Tickets and photo IDs became required to get through the screening area. Laptop computers and electronics had to be removed from carry-on bags. Shoes were taken off. Liquids were restricted to three-ounce containers. And conventional X-ray machines, which only detected metal objects, were eventually replaced with full-body scanners.

Just four days after the 9/11 attacks, a gunman in Mesa, Arizona went on a shooting rampage. First, he shot and killed Balbir Singh Sodhi, a gas station owner of Indian descent. Sodhi was Sikh, so he wore a turban. The gunman assumed he was Muslim. Minutes later, the gunman shot at another gas station clerk of Lebanese descent, but missed, and then shot through the windows of an Afghan-American family.

Before 9/11, people didn’t have to have a ticket to wander around the airport or wait at the gate. No one checked passengers' IDs before boarding the plane. And the only item people had to remove when passing through security was loose change from their pockets. Price says that most airports didn’t bother running background checks on their employees, and checked baggage was never scanned.

FBI conducted surveillance. Long-standing rules meant to protect Americans from “unreasonable search and seizure” were loosened or thrown out in the name of national security.

Congress gave the FBI and NSA new abilities to collect and share data. For example, the Patriot Act gave intelligence agencies the power to search an individual’s library records and internet search history with little judicial oversight. Agents could search a home without notifying the owner, and wiretap a phone line without establishing probable cause.

This law gave the NSA nearly unchecked authorities to eavesdrop on American phone calls, text messages and emails under the premise of targeting foreign nationals suspected of terrorism. 

“If anyone had said this is what they expected the threat to be the day after 9/11, they probably would have been laughed at,” says Sterman. “That would have seemed hopelessly naive.”

Pentagon was hit by hijacked American Airlines Flight 77. Reports circulated that a fourth plane, United Flight 93 out of Newark, New Jersey, was out there. Air command speculated it was also headed to D.C. for another strike on the Pentagon, or a strike on the White House or the Capitol building.

As she powered up the engines, she shouted to the ground crew to pull the chock blocks holding the wheels.

They had agreed upon the plan of attack. Sasseville would head for the 757’s cockpit and Penney would aim for the plane's tail. As they sped out beyond Andrews Air Force Base, flying low at about 3,000 feet, they could see black, billowing smoke streaming from the Pentagon.

Beyond the mission at hand, there wasn’t much else on First Lieutenant Heather Penney’s mind. She had accepted the fate of Flight 93’s passengers, believing whether she succeeded or not, they were going to die. She briefly toyed with the idea of ejecting from her plane just before impact, but quickly dismissed the idea, knowing she had only one shot and didn’t want to miss. It didn’t even cross her mind that there was a possibility the pilot of United Flight 93 was her father, who often flew out of East Coast cities. As it turned out, he wasn’t.

Now the mission changed from intercept to sanitizing the airspace. Not every aircraft aloft that morning was aware the FAA had ordered a national ban on takeoffs of all civilian aircraft regardless of destination. With the assistance of civilian air traffic controllers, Penney and Sasseville began to divert any aircraft away from the D.C. area and ordered them to land as soon as they could. They also identified the first-responding aircraft assisting the rescue at the Pentagon.

Penney and other pilots were instructed to guard the President of the United States as he flew home

In the evening hours, it was time to bring the president home. Penney's plane and the others patrolling the skies around Washington, D.C. had been equipped with live ammunition. They were also given “free-fire” authority, meaning pilots could make the decision to fire on any civilian aircraft deemed to be a threat, instead of waiting for authorization. Several hours after the initial attack, it was still unclear whether more attacks were pending.

"I made a decision with my life and I swore an oath to protect and defend, but these were just average, everyday people, mothers, fathers, school teachers, businessmen," Penney told HISTORY. "They're true heroes."

he quit the Hitler Youth when they participated in Kristallnacht, a night of terror during which Nazi sympathizers destroyed synagogues, set fire to Jewish property and attacked Jews.

According to German propaganda, the Pearl Harbor attack had destroyed the United States’ ability to fight a war in Europe. Hübener provided details to the contrary, assuring Germans that rumors of American military weakness were lies. He disputed official accounts of the war on the Eastern front, too, revealing that despite Germany’s insistence that battles in Russia had been won, they were still raging weeks after propaganda reports that victory had already been achieved.

Hübener’s actions were extremely risky. Radio had helped the Nazis rise to power by spreading their messages to a mass audience. Once the Third Reich took over Germany, they began to use the radio to control the population. They flooded the airwaves with propaganda broadcasts, spreading false reports of glorious victories and bright prospects where there were none.

However, many Germans disobeyed. For people like Hübener, radio from other countries was the only way to learn the truth about the war.

These events upset him, and the teenager began to question the Nazis’ hatred of Jews and the Third Reich’s growing control of German society.

“The Führer has promised you that 1942 will be decisive and this time he will stop at nothing to keep his promise,” he wrote in one pamphlet. “He will send you by the thousands into the fires in order to finish the crime he started. By the thousands your wives and children will become widows and orphans. And for nothing!”

The prison was notorious for its harsh treatment of prisoners and as a site of countless summary executions. For ten weeks, the boys were tortured and intimidated as they awaited trial. When the Nazi head of Hübener’s congregation found out about the arrest, he excommunicated the boy from the Mormon Church

“Don’t you?” His friends later told family members that they thought Hübener was purposely baiting the judges so they’d give the other boys less severe sentences.

That’s exactly what happened. His friends were sentenced to imprisonment in labor camps, but Helmuth Hübener was convicted of conspiracy to commit high treason and treasonous furthering of the enemy’s causes and sentenced to death by beheading. Because his crime was considered so serious, Hübener’s sentence gave the Nazis legal justification for both his execution as a minor and the torture he had already withstood.

On October 27, 1942, guards told Hübener that Adolf Hitler had personally refused to commute his death sentence. Hours later, he was beheaded—the youngest person ever executed by the Third Reich

They were actually thought to encourage good, healthful posture and to keep the internal organs in proper alignment. And the extreme practice of removing ribs to slim the waist, rumored to have flourished in the Victorian era, simply didn’t exist

Today’s approach to gender-specific colors would confuse—and likely amuse—our 19th-century counterparts. White was the preferred color for babies and children of any sex until they reached the age of about 6 or 7, mainly because white clothes and diapers could be bleached. As they grew older, children were dressed in paler versions of the colors adults wore. Red was considered a strong, virile, masculine shade, while blue was dainty, delicate, feminine. So young boys were more frequently seen in pink, while young girls favored pale blue. It wasn’t until the early 20th century—quite possibly as late as the 1940s—that pink began to be universally assigned to girls and blue to boys.

But the fate of southern Black Americans changed in 1916 when news of better jobs and conditions up North started spreading in rural communities. Black newspapers, like The Chicago Defender, ran stories about opportunities for African Americans in steels mills and factories and encouraged them to leave the South.

"They actually interfered with the U.S. Mail to prevent the Defender from being distributed,” says James Grossman, executive director of the American Historical Association and author of Land of Hope: Chicago, Black Southerners and the Great Migration.

“They believed, incorrectly, that what was really happening was Black people were being stirred up by labor agents from northern industries coming South to round up Black workers.

African American field workers waiting to be paid near Homestead, Florida, 1939.Photo 12/Universal Images Group via Getty Image

“Police literally went up to the platforms and rounded people up,” says Grossman, to dissuade Black people from traveling. And the intimidation tactic worked.

A common belief among white southerners was that Black people were intellectually inferior and would not think to move to the North in search of better opportunities.

Black Americans who fled racial oppression either returned to retrieve the rest of their family or sent train tickets back home. In response, as white southerners observed train platforms packed with African Americans, several cities passed ordinances that made it illegal for trains to accept pre-paid tickets.

Although there were instances of African Americans being recruited to work as Pullman porters on railways and seasonally on tobacco farms in Connecticut, the true northern labor agents were African Americans themselves, says Grossman.

Still, the Great Migration powered on. With a promise of a better life, more dignity and employment, African Americans began to leave from a train station further away, so they wouldn’t be recognized by locals or police officers.

White southerners, anticipating more labor shortages, utilized the mechanical cotton picker more in the 1940s, often evicting Black sharecroppers from their land, who in turn migrated elsewhere in search of work. These developments cemented the African American pilgrimage from the South until the 1970s.

It’s easy to take the zipper for granted today, but before it was invented, getting (and staying) dressed involved securing clothing with ropes, ties, buttons or other fasteners.

After years of attempts, Bell achieved his goal of transmitting sound over a wire, and on March 7, 1876, obtained his first U.S. Patent for a device he labeled as “Improvement on Telegraphy”—now better known as the telephone.

The first World’s Fair to take place in the United States was held in Philadelphia in 1876, and also celebrated the 100th anniversary of the country’s founding.

Then, in 1893, inventor Whitcomb L. Judson received a patent for his “clasp locker” shoe fastener, and immediately partnered with businessman Colonel Lewis Walker to launch the Universal Fastener Company and manufacture his invention

Along with the zipper, the Garis-Cochran Dishwashing Machine was also first introduced to the public at the 1893 Chicago World’s Fair, in a display drawing crowds curious about the contraption capable of thoroughly washing and drying 240 dishes in two minutes. The crowd-pleasing exhibit was more than a decade in the making. In 1883, Ohio entrepreneur Josephine Garis Cochran grew frustrated with the amount of time it took to clean up after dinner parties, reportedly saying, “If nobody else is going to invent a dishwashing machine, I’ll do it myself.” And she did.

One of the biggest challenges that arose during the early days of electricity was getting it from the power source to an individual device. By the 1880s, entire houses were being wired for electricity, but electrical appliances had to be connected to the home’s main power source directly, posing serious safety risks to members of the household.

April 30, 1939, New York City: This is the scene viewed on the television receivers in the metropolitan area, as the National Broadcasting Company inaugurated the first regular television service to the American public telecasting the ceremonies marking the opening of the New York World's Fair. Bettmann via Getty Images

May 1, 1939 saw another television milestone: the launch of a regular television broadcast schedule on the National Broadcasting Company (NBC), which was owned by RCA.

Fairgoers could take what was advertised as “America’s first television tour” (presented by NBC), where they would learn about the history of the medium, as well as the science and engineering that made its broadcast possible.

In the age of smartphones, it’s easy to identify the touchscreen demonstration at the World’s Fair as a significant technological turning point, but according to Jack Neely, executive director of the Knoxville History Project and crowd controller at the World’s Fair, that wasn’t apparent at the time. “It was...one of those things you had to look fast to notice,” Neely told the University of Tennessee Daily Beacon in a 2017 interview.

That’s why the Union Army’s first offensive action of the Civil War was to cross the Potomac into Virginia in the early morning of May 24, 1861 and capture high ground in Alexandria and Arlington, including the family estate of Confederate General Robert E. Lee (which eventually became Arlington National Cemetery). The Union infantry quickly dug the first earthen forts, Fort Runyon and Fort Corcoran, to prevent the Confederates from installing cannons that could easily strike the capital.

The formidable task of fortifying Washington, D.C. fell to Major General John Barnard, a respected Army engineer. Winkle says Barnard quickly recognized that the greatest challenge was Washington, D.C.’s sprawling layout, the result of architect Pierre L’Enfant’s ambitious grid design

Over the winter of 1861 and 1862, Barnard directed a team of Army engineers, soldiers, formerly enslaved people and prisoners of war to build the first 37 earthen forts that created a 35-mile defensive perimeter around the capital.

“This is a very precarious position,” says Winkle, adding that Washington, D.C.’s other border was with Maryland, a slave state whose loyalty to the Union was shaky at best

In between the forts were 20 miles of earth-dug trenches known as rifle pits.

During the drawn-out conflict, the Confederate Army made several sorties in the direction of Washington, D.C.—Winkle says that both the Battles of Antietam and Gettysburg were primarily designed to threaten the Union capital—but the city only suffered one direct attack.

Lincoln wanted Washington, D.C. to be continuously defended by at least 30,000 regular infantry, but that wasn’t possible in the summer of 1864 when General Ulysses S. Grant desperately needed reinforcements in Virginia. By July, only 9,000 Union troops—mostly green new recruits and disabled reserves—were left to defend the capital and the Confederacy saw a golden opportunity.

Lieutenant General Jubal A. Early led 14,000 Confederate troops across the Potomac River into Maryland and then circled around to attack the Union capital from the north. On July 11, 1864, Early’s army arrived at Fort Stevens, where Lincoln himself stood with the shaky Union forces.

The dejected Confederate general concluded that “every appliance of science and unlimited means had been used to render the fortifications around Washington as strong as possible.”

"Please have that conversation tonight. We're talking about seventh graders. It's never too early to have that conversation," he said.

Fentanyl is 80 to 100 times stronger than morphine, according to the DEA, and many of its derivatives, like carfentanil, are even stronger.

“What we’ve learned is that every variant seems to have its own characteristics, and it’s important that we not be locked into thinking we know everything based on what we’ve learned from the last variant,” he said

“The virus grows in your nose and throat and somewhat at different time scales,” Michael Mina, chief science officer for the biotech software company eMed, who was an assistant professor of epidemiology at the Harvard T.H. Chan School of Public Health, said at a testing technology news briefing this week.

“The agency recommends that individuals closely follow the tests’ instructions,” FDA spokesperson Jim McKinney told NBC News in an email.

Dr. Jonathan Li, an infectious disease physician at the Brigham and Women’s Hospital in Boston, cautions against altering the testing strategy that has been validated and authorized by the FDA.

The United Kingdom’s National Health Service recommends swabbing both the nose and the throat when using a rapid antigen, or later flow, Covid test, the kind used at home.

Before advocating the altered approach, Li said, he would need to see data that showed it was effective. User error will likely be higher with self-administered throat swabs compared with nasal swabs, he said.

“The nose and the throat have different pH levels and we have seen people take Coke or coffee and put it in an antigen test and had a line to appear,” she said. “We don’t know exactly why this happens, but the hypothesis is acidity.” 

Miller notes that a small preprint paper out of South Africa, which has not yet been peer-reviewed, suggested that more detectable virus may reside in the throat than in the nose when a person is infected with omicron compared to the delta variant, though the study compared PCR to antigen, or rapid, tests, which are not the same type of tests. 

Miller said that although she would not be surprised if omicron indeed does show up in the throat before it does in the nose, that concrete data has yet to be shown. 

According to Matt Binnicker, director of clinical virology at the Mayo Clinic, the fact that positivity rates are soaring in the U.S. is a testament to how well Covid tests are still working.

According to Miller, it’s best to take a rapid test on day one, day two and day three of symptoms if you are testing negative but your symptoms persist. You should also isolate. “If you have symptoms, you have Covid until proven otherwise,” she said. 

ucing snowfall in the northern Plains and the Upper Midwest, with heavy snow in parts of Minnesota and Iowa coming down at rates of one to two inches per hour

In a weekend forecast, NBC’s "TODAY" weather anchor Al Roker said the storm system could bring 6 to 12 inches of snow stretching from the Dakotas down to Missouri.

Snow is also expected to develop over parts of the central and southern Appalachians, with pockets of rain and freezing rain potentially developing over the Carolinas and the southern Appalachians overnight Saturday into Sunday morning.

Roker said the system was expected to move south before making its way up the Eastern coast into Sunday and Monday, bringing heavy wind and rain if it continues along its expected track. On Sunday, a wintry mix is expected to hit parts of the Southeast, including Atlanta, as a significant ice storm unfolds across the Carolinas.

Andy Stone, a spokesperson for Meta, responded in a statement saying, "As Chairman Thompson said recently, 'Facebook is working with [the committee] to provide the necessary information we requested.'

"To this day, YouTube is a platform on which user video spreads misinformation about the election," the committee said.

In a statement, Google said: “We’ve been actively cooperating with the Select Committee since they started their investigation, responding substantively to their requests for documents, and are committed to working with Congress through this process.

A Reddit spokesperson said, "We received the subpoena and will continue to work with the committee on their requests."Twitter declined to comment.

The panel first sought records from the four companies and others in August, asking for information related to "the spread of misinformation

The committee is seeking information dating to the spring of 2020.

FBI officials have acknowledged that there were calls for violence at the Jan. 6 "Stop the Steal" rally by Trump supporters, which was held just before the Capitol attack, but they have said the calls did not add up to specific, credible intelligence.

Testifying before a Senate committee in March, FBI Director Christopher Wray suggested that the amount of vitriol online makes it difficult to sort out.

Psaki added that Russians appear to be following the same playbook they used when they took control of Crimea.

The comments came hours after Ukraine was hit by a massive cyberattack warning its citizens to “expect the worst.” Ukraine’s foreign ministry spokesperson told Reuters it was too early to say who could be behind the attack, but that Russia had been behind similar strikes in the past.

Russia has massed more than 100,000 troops on its neighbor’s frontier. The Russian government has denied it has plans to attack Ukraine, but aired footage of more forces deploying to the area on Friday. Russian officials met with their U.S., European and NATO counterparts over the past week as they sought defuse tensions between the two countries.

The threats have had an impact on her and she worries that speaking out about it could make her more of a target. Other lawmakers declined to speak with CBS News because they didn't want to normalize the violent threats. "I'm trying not to let it get to me," Dingell said. "But it doesn't mean that some nights when you're home and alone and you don't have the husband you love anymore, you don't get scared."A year after the January 6 riot, the Capitol Police says the threats to lawmakers are at an all-time high. Roughly 9,600 threats were referred to the agency in 2021, about 100 more than in 2020. 

"We're being stretched. Let's be blunt. We're being stretched. We're keeping up, but this is not an ideal situation," he added. Capitol Police flagged about 460 threats against lawmakers' lives last year. 

Threats against lawmakers rise when members of Congress take rhetorical aim at colleagues, according to Scalora. After Colorado Republican Lauren Boebert likened Minnesota Democrat Ilhan Omar to a suicide bomber, both received threats.

The Capitol Police is now looking to investigate more of those threats itself and rely less on other agencies. Manger's intelligence unit has doubled the number of analysts available to monitor the threat landscape, especially online. The department is also looking to add 280 new officers this year and is opening field offices in California and Florida to investigate these threats more efficiently. 

President Biden first announced the rules in September as part of a broader strategy from his administration to combat the spread of the Delta variant, which drove a surge of infections toward the end of the summer. 

The Supreme Court was asked to intervene last month and swiftly held oral arguments to weigh the emergency requests.

"As a result of the court's decision, it is now up to states and individual employers to determine whether to make their workplaces as safe as possible for employees, and whether their businesses will be safe for consumers during this pandemic by requiring employees to take the simple and effective step of getting vaccinated," Mr. Biden said. "The court has ruled that my administration cannot use the authority granted to it by Congress to require this measure, but that does not stop me from using my voice as president to advocate for employers to do the right thing to protect Americans' health and economy."

The Biden administration estimated that more than 80 million employees could be impacted by the policy.

The Supreme Court received more than a dozen requests for emergency action in cases challenging the requirement after the 6th U.S. Circuit's ruling, with business associations, Republican-led states and private businesses covered by the rule arguing OSHA lacked the power to issue the vaccine requirement.

"Permitting OSHA to regulate the hazards of daily life — simply because most Americans have jobs and face those same risks while on the clock — would significantly expand OSHA's regulatory authority without clear congressional authorization," the court said.

The second rule examined by the Supreme Court was issued by the Centers for Medicare and Medicaid Services (CMS) in November and laid out vaccine requirements for staff at a wide range of facilities that participate in Medicare and Medicaid. The requirement does not have a daily or weekly testing option for unvaccinated workers, but does include medical and religious exemptions.

. Then, in a separate case brought by 14 states, a federal district court in Louisiana blocked the rule from taking effect nationwide, but the 5th Circuit narrowed the scope of the order to the 14 states that together sued the Biden administration. 

"After all, ensuring that providers take steps to avoid transmitting a dangerous virus to their patients is consistent with the fundamental principle of the medical profession: first, do no harm," the Supreme Court said.

"The omnibus rule is undoubtedly significant — it requires millions of healthcare workers to choose between losing their livelihoods and acquiescing to a vaccine they have rejected for months. Vaccine mandates also fall squarely within a state's police power, and, until now, only rarely have been a tool of the federal government," Thomas wrote. "If Congress had wanted to grant CMS authority to impose a nationwide vaccine mandate, and consequently alter the state-federal balance, it would have said so clearly. It did not."

The various peaks represent times in which each nation was hit by a new Covid wave, including the initial outbreak and influx of hospital patients, last winter's surge or the summer spike caused by the Delta variant.

Hospitals around the US have reported that the spike in infected patients has exacerbated pressure on facilities already strained by the pandemic.Dr Juan Reyes, the director of hospital medicine at George Washington University in Washington DC - which is among the US cities with the highest per capita hospital admissions rate - said that this surge "has been a lot more challenging" than previous ones.

In South Africa - where the Omicron variant was first detected in November - researchers found that those infected with Omicron are less likely to be sent to hospital and more likely to recover quickly.

Experts point to several reasons why the rate of Covid patients in hospital is higher in North America than in most other parts of the world.Professor David Larsen, an epidemiologist and global health expert at Syracuse University in New York, told the BBC that the US population is markedly different from that of both Europe and South Africa.

"The seasonality is also different," he said. "Omicron's surge through South Africa was during their summer,

Just over 63% of the US population is fully vaccinated, much lower than in the UK (71%) as well as Italy and France (both 75%). In Canada, almost 79% of the population is fully protected.

"incongruent" public health policy when it comes to Covid-19."In other words, there isn't a single unified method in how we're going to do things across the board," he said. "It's more regional than national, and because of that you have gaps. The consequences of that are people getting hospitalised."

the true figure is hard to determine."We don't know how much Delta there is," she told the BBC. "What the US has started to do is look at the number of new infections and sequences. Omicron is 95% of new infections, but we don't know how much Delta we still have around."

In many countries, researchers believe that the Omicron variant has begun to subside, possibly signalling the end of the increase in hospital patients with Covid.

"It still could make for a miserable winter," Dr Gandhi said. "I think that for the next month, life is going to be really hard in schools and hospitals

"I was the only black girl in those clubs," she recalls. "There weren't really a lot of activities around STEM that you could do in my neighbourhood. So, I found myself sort of leaving my south side community and going elsewhere - to get exposure to certain activities."

When she graduated and became a research chemist she noticed another trend.

Researchers say that the 'leaky pipeline' refers to women, and particularly women of colour, facing many barriers and obstacles to advancing further in their fields, from childcare obligations to fewer promotion opportunities.

Cynthia had an idea whilst doing her masters in 2015, that she would create a club to pull more women like her in to the world of science. By 2018, Black Girls Do STEM became an after-school community in St Louis, Missouri - where she now lives

The fortnightly classes used to be held in person but have moved online throughout the pandemic.