In 2020, life changed across the globe.

COVID-19 is an infectious disease caused by a virus called SARS-CoV-2. Though initially discovered in Wuhan, China, in late 2019, COVID-19 entered the conversation in the U.S. in January 2020. At that time, the Centers for Disease Control and Prevention (CDC) alerted the nation of the outbreak abroad.

Later in January 2020, the first U.S. case of COVID-19 was reported in the state of Washington.

The outbreak escalated quickly from there. For a while, experts didn't know how the virus behaved. They didn't know how it spread or how quickly. They didn't know how much of a threat it was to public health. COVID-19 tests were still in development and were not readily available to the public.

By March 2020, the World Health Organization (WHO) declared COVID-19 a global health emergency. They named the virus "severe acute respiratory syndrome coronavirus 2" or "SARS-CoV-2."

In March 2020, the WHO officially declared the COVID-19 outbreak a pandemic.

In May 2023, the WHO and former U.S. President Joe Biden declared an end to the pandemic. Here’s what happened along the way.

March 2020

• WHO declares pandemic.

April 2020

• U.S. announces Operation Warp Speed to develop a COVID-19 vaccine as quickly as possible.

June 2020

• U.S. reports 2 million cases.

August 2020

• COVID-19 becomes 3rd leading cause of death in the U.S.

September 2020

• Global deaths reach 1 million.

December 2020

• The Food and Drug Administration (FDA) issues Emergency Use Authorization (EUA) for COVID-19 vaccines.

January 2021

• New COVID-19 variants are reported in the U.S. and across the globe.

February 2021

• COVID-19 cases surpass 100 million worldwide, with 2 million deaths.

March 2021

• Over 100 million COVID-19 vaccine doses have been given in the U.S.

October 2021

• WHO defines "long COVID-19." Long COVID is a combination of symptoms people may have three months after they test positive for COVID-19. These symptoms may last for at least two months and include fatigue, shortness of breath and cognitive dysfunction.

November 2021

• WHO declares omicron variant of COVID-19 a “variant of concern.”
• The FDA approves booster mRNA vaccines for everyone ages 18 and older. 

January 2022

• Omicron variant surges in the U.S., accounting for 99% of COVID-19 cases.
• FDA fully approves the Moderna COVID-19 vaccine for people ages 18 and older.

March 2022

• WHO shows pandemic increased anxiety and depression by 25% worldwide — especially in young people and women.
• FDA authorizes second booster dose of mRNA vaccines for adults ages 50 and older and people who are immunocompromised.

June 2022

• More than 84 million COVID-19 cases are recorded in the U.S.

July 2022

• The FDA approves the Pfizer-BioNTech COVID-19 vaccine for people ages 12 to 15, following EUA in May 2021.

February 2023

• Worldwide tally reaches 755 million COVID-19 cases and 6.8 million deaths.

May 2023

• The WHO declares an end to the COVID-19 pandemic.
• U.S. President Joe Biden ends national and public health emergencies for COVID-19.

COVID-19 still circulates among the global population. Talk to your primary care clinician about the COVID-19 vaccine and learn what COVID-19 symptoms look like.