Dec. 31, 2019: First report of a cluster of pneumonia cases in China.

Jan. 1, 2020: Johns Hopkins begins its response, activating the alert phase for the Johns Hopkins Medicine Office of Emergency Management, the Office of Critical Preparedness and Response (CEPAR), and the Department of Hospital Epidemiology and Infection Control (HEIC).

Jan. 21, 2020: First U.S. coronavirus case confirmed in Washington state.

Jan. 22, 2020: The Johns Hopkins University and Johns Hopkins Medicine launch the Coronavirus Resource Center, which rapidly becomes a premier source around the world for real-time, accurate data about the pandemic. Its dashboard, created by Whiting School of Engineering civil and systems engineering associate professor Lauren Gardner and others, has been viewed more than 1 billion times. On Dec. 18, 2020, it adds a tool for tracking the national vaccination rollout.

Jan. 27, 2020: Johns Hopkins Medicine publishes its first coronavirus article, “What Is Coronavirus?” A year later, the Johns Hopkins Medicine coronavirus website has published more than 200 pages of content, attracting 55 million visits. The HEIC incident command center begins operations.

Feb. 11, 2020: Johns Hopkins experts, including Lauren Sauer, director of operations with CEPAR, lead a panel discussion at the Johns Hopkins Bloomberg School of Public Health. They announce that the World Health Organization has named the virus as SARS-CoV-2 and the disease it causes as COVID-19.

March 3, 2020: The JHM Unified Incident Command Center is established to coordinate the COVID-19 response across the Johns Hopkins Health System and the Johns Hopkins University School of Medicine.

March 4, 2020: Sibley Memorial Hospital admits a stroke patient who is diagnosed on March 12, 2020, with COVID-19.

March 5, 2020: Maryland records its first COVID-19 cases and enters a state of emergency.

March 6, 2020: A panel of Johns Hopkins experts testifies to Congress, sharing what it knows about the coronavirus outbreak.

March 11, 2020: The World Health Organization declares that COVID-19 is a pandemic. The National Basketball Association cancels the rest of its season. The Johns Hopkins University announces that students will transition to remote study after spring break. Johns Hopkins clinical microbiologists Karen Carroll and Heba Mostafa develop an in-house COVID-19 polymerase chain reaction test for virus detection.

March 12, 2020: Maryland records its first case of community transmission. The Johns Hopkins Hospital admits its first patient with COVID-19, who is treated in the hospital’s biocontainment unit and discharged March 16, 2020. New visitor restrictions across Johns Hopkins Medicine allow one visitor per patient and require screening of visitors for symptoms or possible exposure.

March 13, 2020: Howard County General Hospital and Suburban Hospital each admit their first patient with COVID-19.

March 14, 2020: Corporate supply chain team members gather at the Consolidated Service Center in Baltimore to assemble face shields and create Personal Protection Packs containing masks, a face shield, hand sanitizer, and instructions to safely store and reuse personal protective equipment. They make more than 25,000 face shields in less than two weeks.

March 15, 2020: The Johns Hopkins University transitions to remote learning, and ramps down on-campus lab-based and clinical research activities.

March 16, 2020: Maryland public schools, state buildings and the Port of Baltimore close, along with bars, restaurants and recreational businesses. Gov. Larry Hogan prohibits gatherings of more than 50 people and mandates telework for state employees.

March 17, 2020: The Johns Hopkins Health System begins converting units to safe care for patients with COVID-19, starting with Meyer 9 at The Johns Hopkins Hospital. A medical intensive care unit at the hospital is converted March 18, and a second on March 25. Facilities personnel alter air handling to create negative pressure and build spaces for safe donning and doffing of personal protective equipment across the health system, in keeping with infection control practices developed by HEIC and nursing experts.

March 17, 2020: The school of medicine suspends elective rotations and other clinical experiences for students. The health system diagnoses its first pediatric patient with COVID-19, at Howard County General Hospital.

March 18, 2020: First Maryland death from COVID-19. Johns Hopkins member organizations cancel elective surgeries, following jurisdictional guidance, in order to re-allocate resources to care of patients with COVID-19.

March 25, 2020: The Employee COVID-19 Call Center launches to answer questions about symptoms, exposure or possible need for COVID-19 coronavirus testing.

March 29, 2020: Johns Hopkins Children’s Center diagnoses its first pediatric patient with COVID-19.

March 30, 2020: Hogan issues a stay-at-home order: “No Maryland resident should be leaving their home unless it’s for an essential job or an essential reason such as obtaining food or medicine, seeking urgent medical attention or for other necessary purposes.” It is replaced May 15, 2020, with a “safer at home” advisory that allows limited retail shopping, manufacturing, worship services and haircuts.

April 23, 2020: Johns Hopkins Medicine staff is required to wear face shields, in addition to face masks or respirators, when in close contact with or caring for all patients.

April 27, 2020: Johns Hopkins and the University of Maryland open a field hospital at the Baltimore Convention Center.

April 30, 2020: Correspondence from Johns Hopkins researchers published in The Lancet provides insights into why some people get sicker than others, highlighting obesity as a risk factor for COVID-19 severity.

May 18, 2020: Six Johns Hopkins ambulatory surgery centers re-open for select elective adult and pediatric surgeries and procedures. Additional in-person care returns to Johns Hopkins hospitals and clinics starting June 3, 2020.

May 27, 2020: The U.S. passes 100,000 COVID-19 deaths, according to the Johns Hopkins Coronavirus Resource Center.

June 15, 2020: The National COVID Cohort Collaborative launches, co-led by Johns Hopkins Medicine investigators. The centralized and secure COVID-19 database provides information for big data studies of the disease.

June 15, 2020: Johns Hopkins labs re-open with reduced capacity and improved cleaning protocols. The new system is supported by the Prodensity app, developed by the Johns Hopkins Technology Innovation Center to provide COVID-19 health checks and to track how many people are in labs and other common spaces.

June 18, 2020: Johns Hopkins research published in the Journal of the American Medical Association highlights COVID-19 disparities, noting, “More than 40% of Latinos in the Baltimore-Washington, D.C., metropolitan region who were tested for SARS CoV-2 were positive, a much higher proportion than for any other racial/ethnic group.”

Aug. 11, 2020: Johns Hopkins Medicine receives $35 million from the U.S. Department of Defense to test the effectiveness of a convalescent blood plasma outpatient treatment.

Sept. 22, 2020: The U.S. passes 200,000 coronavirus deaths, according to the Johns Hopkins Coronavirus Resource Center.

Oct. 2, 2020: President Donald Trump tests positive for the coronavirus that causes COVID-19. His treatment team includes Brian Garibaldi, director of the Johns Hopkins biocontainment unit and associate professor in the Division of Pulmonary and Critical Care Medicine.

Dec. 11, 2020: The U.S. Food and Drug Administration (FDA) issues emergency authorization of a COVID-19 vaccine developed by Pfizer and BioNTech SE.

Dec. 14, 2020: The U.S. passes 300,000 coronavirus deaths, according to the Johns Hopkins Coronavirus Resource Center.

Dec. 16, 2020: Occupational therapist Kelly Casey is the first employee at The Johns Hopkins Hospital to be vaccinated against COVID-19.

Dec. 18, 2020: The FDA issues emergency use authorization for the Moderna COVID-19 vaccine.

Jan. 19, 2021: The U.S. passes 400,000 coronavirus deaths, according to the Johns Hopkins Coronavirus Resource Center.

Jan. 20, 2021: In partnership with the District of Columbia Housing Authority, Johns Hopkins Medicine begins bringing vaccinations to senior citizens living in public housing in Washington, D.C.

Jan. 25, 2021: The Johns Hopkins University spring semester begins as scheduled, with limited in-person classes. Vaccine eligibility in Maryland expands to include residents ages 65 to 74.

Feb. 4, 2021: The Baltimore Convention Center field hospital, jointly operated by Johns Hopkins Medicine and the University of Maryland Medical System, begins administering antibody therapies to eligible patients.

Feb. 22, 2021: The U.S. passes 500,000 coronavirus deaths, according to the Johns Hopkins Coronavirus Resource Center.

Feb. 24, 2021: Johns Hopkins passes the milestone of dispensing more than 100,000 COVID-19 vaccine doses to employees, patients and community members.

Feb. 25, 2021: Johns Hopkins Medicine begins bringing vaccine clinics to underserved parts of Baltimore, in collaboration with the city and other local health systems.

Feb. 27, 2021: The FDA issues emergency use authorization for a single-dose Johnson & Johnson vaccine. Nearly one year after the first patients with COVID-19 came to Johns Hopkins, the health system has treated 6,584 people for COVID-19.

March 8, 2021: Johns Hopkins Medicine has fully vaccinated 31,858 employees, provided at least one dose of vaccine to 33,798 employees, and provided 60,104 first and second doses to patients and community members in Maryland, Washington, D.C., and Florida.