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From Wuhan to the White House: A timeline of COVID-19’s spread

  • Oct. 12-13: Medical trials paused

    Johnson & Johnson, one of the first American pharmaceutical companies to produce a COVID-19 vaccine, paused its clinical trial on Oct. 12 due to an illness in one of the study's 60,000 patients. The next day, Eli Lilly, another pharmaceutical, paused its 300-person trial of a potential COVID-19 treatment which mimics the body's natural immune response to the disease, due to a safety concern from the FDA.

    Both pauses were natural parts of the scientific process; as clinical trials include hundreds (or even thousands) of people, scientists must take every possible precaution to ensure the safety of their patients. Pauses are usually not communicated to the public, but as American institutions race to bring safe vaccines and life-saving treatments to the public, every small hurdle in this complicated process is under immense scrutiny.

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  • Nov. 4: US passes 100,000 new cases in one day

    On Nov. 4, state public health departments reported a total of 103,000 new COVID-19 cases—a national record for the most new cases in one day, according to the COVID Tracking Project. The nation continued to set records for the next three days, culminating in 128,000 new cases reported on Nov. 7. During the week of Nov. 1 to 7, approximately one in every 460 Americans was diagnosed with COVID-19.

    Unlike previous COVID-19 outbreaks in the U.S., which were largely focused in one geographic region, this new surge of cases is reflected in increases across the country.

  • Nov. 9, Nov. 16: Preliminary vaccine clinical trial data released

    Pharmaceutical company Pfizer and its partner BioNTech announced on Nov. 9 that their COVID-19 vaccine had demonstrated initial success in a large-scale clinical trial. The trial has enrolled 44,000 participants, 94 of whom had been diagnosed with COVID-19 at the time that Pfizer conducted its preliminary analysis. The company's results show that, among these 94 patients, those who received the vaccine were 90% less likely to be diagnosed with the disease.

    One week later, Moderna, the producer of another COVID-19 vaccine that uses similar technology to Pfizer's, announced its own preliminary results. Among 100 patients in Moderna's trial diagnosed with COVID-19, those who received this company's vaccine were 94.5% less likely to be diagnosed with the disease. Both companies' results are considered very promising by public health experts who expected that a COVID-19 vaccine may only be 60% effective.

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  • Nov. 29: United States has busiest air travel day since pandemic began

    As the United States passed 12 million COVID-19 cases the weekend before Thanksgiving, U.S. health officials encouraged Americans to not travel during the holidays and limit festivities to small or virtual gatherings. However, U.S. airports still flooded with people during the long weekend. The Transportation Security Administration reported that over 1.17 million travelers across the country were screened by TSA agents on the Sunday following Thanksgiving, the highest number of air travelers since March. Each day of Thanksgiving weekend—Thursday through Sunday—saw over a million people pass through TSA screenings.

  • Dec 2: US hospitals caring for more than 100,000 COVID-19 patients

    On Dec. 2, the U.S. reported about 100,300 Americans in the hospital with COVID-19. Prior to November, the nation’s record for the most COVID-19 patients hospitalized at one time was about 60,000. December’s record, which continued to climb past 105,000, reflected health care systems across the nation that are more challenged than ever before in taking care of patients.

  • Dec. 8: Joe Biden announces 100-day plan to combat the pandemic

    President-elect Joe Biden announced the three-part plan he will initiate upon entering office to tackle the COVID-19 crisis, focusing on masks, vaccinations, and reopening schools across the country. His plan includes issuing a federal mask-wearing mandate and overseeing at least 100 million COVID-19 vaccinations during the first 100 days.

    Biden also nominated several members to the team that will lead the COVID-19 response during his presidency. Among them are Massachusetts General Hospital Chief of Infectious Diseases Dr. Rochelle Walensky for director of the CDC, California Attorney General Xavier Becerra for leading the Department of Health and Human Services, and Dr. Vivek Murthy to reclaim his Obama-era position as surgeon general.

  • Dec. 11: FDA grants emergency authorization for Pfizer vaccine

    When the FDA is asked to endorse the distribution of a new vaccine, the agency calls a panel of outside experts to carefully consider all available scientific evidence and recommend whether the safety benefits of this vaccine outweigh the risks. On Dec. 10, that advisory panel met, discussed evidence, and voted to recommend that Pfizer and BioNTech’s COVID-19 vaccine should go to market for all Americans aged 16 and over.

    The next day, the FDA followed its committee's recommendation by officially granting the vaccine Emergency Use Authorization. Moderna’s vaccine was up next.

  • Dec. 18: Emergency authorization for Moderna vaccine

    One week after the FDA granted Pfizer and BioNTech's COVID-19 vaccine Emergency Use Authorization, the agency granted authorization to Moderna's vaccine. Moderna's vaccine, like Pfizer's, uses messenger RNA—specially designed genetic material that triggers your body's immune system to prepare for an attack by the novel coronavirus without actually encountering the virus itself.

    The two vaccines now available in the U.S. have both been highly effective in clinical trials and appear to reduce risk of serious COVID-19 illness, though scientific understanding about how well both vaccines work will improve in the months to come. Dr. Anthony Fauci, who received his first dose of Moderna's vaccine on Dec. 22, said he feels "extreme confidence in the safety and efficacy of this vaccine" and encourages other Americans to get vaccinated.

  • Dec. 27: Trump signs second stimulus package

    Facing the prospect of another government shutdown, Trump signed the $2.3 trillion bill that Congress presented to him six days prior, which includes federal funding for 2021 and another stimulus package for Americans. After initially opposing the bill and urging Congress to increase stimulus check payment amounts to $2,000, the president acquiesced and put into law a $900 billion stimulus package that will send $600 stimulus payments to eligible Americans, as well as add $300 to unemployment benefits and extend the benefits until March. The bill also provides funding for schools, transportation, vaccine distribution, rental relief, and additional funding for the Paycheck Protection Program.

  • Dec. 29: First B.1.1.7 case detected in the US

    A new variant of the novel coronavirus, called the B.1.1.7 variant, was found in the U.K. in September. The variant has many similarities to the existing coronavirus strain that has infected millions, and early research suggests that Pfizer and Moderna's vaccines should be effective in curbing illness caused by the strain. But this new variant is much more contagious, making it a significant threat to the U.S. at a time when hospitals are already under strain with COVID-19 patients at an all-time high.

    As of Jan. 20, 2021, 144 B.1.1.7 cases have been detected in the U.S., according to the CDC. This number is likely a significant undercount, however, as the U.S. does not systematically identify the genetic sequences of coronavirus DNA in patients—a process which is necessary to distinguish the new variant from the older, more-prevalent coronavirus strain. The U.S. has sequenced fewer than 1% of its cases, while the U.K. has sequenced about 10%.