EPI’s COVID-19 forecast model: April 23, 2020

Attribution

For additional COVID-19 models by this author and additional team members, please visit the Global Epidemic and Mobility Modeling (GLEAM) project site or hop to the team section.

Findings

Projection of the entire U.S.

Even with the current level of social distancing and closures, the epidemic will affect virtually the entire country by May 1, 2020.

Two heat maps that charts the unmitigated projections and the social distancing projections in the United States.
Even with the current level of social distancing and closures, the epidemic will affect virtually the entire country by May 1, 2020.

Projection of cumulative infections and incidence of deaths with current mitigation

  • Models point to days around April 8, 2020 as the peak time for deaths in the U.S.
  • Based on the last projection, a total of 52,000 COVID-19 deaths are currently projected through April 30, 2020.
  • We project that about 4 percent of the U.S. population will have been infected by April 20, 2020.
A line graph that charts the infection and death projections for the United States. Beneath is a table that gives the total deaths and cumulative infection attack rates for unmitigated projections and social distancing projections.
Projection of cumulative infections and incidence of deaths with current mitigation.

Projection for the state of Florida

  • Estimate around April 14, 2020 as the peak time for deaths in Florida.
  • We project that about 2.8 percent of Florida’s population will have been infected by April 20, 2020.
  • Thus, lifting mitigation will result in large epidemic.
A line graph that charts the infection and death projections for the state of Florida from February 15, 2020 to April 30, 2020.
Infection projections and death projections for the state of Florida.

Projected ICU and hospital bed use for state of Florida

A line graph that charts the ICU and hospital bed projections for Florida from February 15, 2020, to April 30, 2020.
Projected ICU and hospital bed projections for the state of Florida.

Projected effects of different mitigation efforts

A line graph charts the projected effects of different mitigation efforts from March 01, 2020, to August 30, 2020.
Projected effects of different mitigation efforts to decrease the spread of infection.
  • Purple line: Schools closed, everything else goes back to normal on May 1, 2020.
  • Red line: Nonessential business open but schools and universities closed, smart working for about 50 percent of people; restaurant, bars and mass gatherings shut down.
  • Green line: The same as red, plus enhanced testing with contact tracing.
  • Blue line: Stay at home order prolonged after May 1, 2020.

Projected effects of different mitigation efforts plotted with ICU and hospital bed capacity

A line graph charts the projected effects of different mitigation efforts on ICU and hospital bed capacity from March 1, 2020, to August 30, 2020.
Projected effects of different mitigation efforts plotted with ICU and hospital bed capacity.
  • Thick dashed line: Intensive care unit capacity
  • Thin dashed line: One-third of intensive care unit capacity
  • Purple line: Schools closed, everything else goes back to normal on May 1, 2020.
  • Red line: Nonessential business open but schools and universities closed, smart working for about 50 percent of people; restaurant, bars and mass gatherings shut down.
  • Green line: The same as red, plus enhanced testing with contact tracing.
  • Blue line: Stay at home order prolonged after May 1, 2020.

Boston: modeling mitigation strategies, second wave

Two line graphs chart the daily infection and cumulative infection during the second wave from February 19, 2020, to December 23, 2020.
Source:  Aleta, et al. Modeling the impact of social distancing, contact tracing and household isolation on second-wave scenarios of the COVID-19 epidemic.  Forthcoming publication on GLEAM site.
  • Staged reopening without testing but with contact tracing results in a large second wave of infections.
  • If 20 percent or more of the contacts of detected symptomatic individuals are traced and put into quarantine, the epidemic is controlled.

Conclusion

  1. Return to normal will result in a big, epidemic surge, i.e. a second wave.
  2. Epidemic will continue to decline and reach a low endemic level as long as social distancing is in force. However, the infection will not disappear.
  3. Go slowly with easing social distancing and watch trajectory of epidemic.
  4. Large scaled testing, contact tracing, and treatment preparation is necessary to lift social distancing. Some level of social distancing must stay in place.

Ira M Longini

Ira M Longini

Professor
Department: PHHP-COM BIOSTATISTICS
Phone: (352) 294-1938

Dr. Longini received his Ph.D. in Biometry at the University of Minnesota in 1977. He began his career with the International Center for Medical Research and Training and the Universidad del Valle in Cali, Colombia, where he worked on tropical infectious disease problems and taught courses in biomathematics. Following that, he was a professor biostatistics at the University of Michigan, Emory University and the University of Washington. He currently is a professor of biostatistics at the University of Florida and Director of the Center for Statistical and Quantitative Infectious Diseases (CSQUID), the Emerging Pathogens Institute, at the University of Florida. His research interests are in the area of stochastic processes applied to epidemiological problems. He has specialized in the mathematical and statistical theory of epidemics–a process that involves constructing and analyzing mathematical models of disease transmission, disease progression and the analysis of infectious disease data based on these models. He works extensively in the design and analysis of vaccine and infectious disease prevention trials and observational studies. Dr. Longini has worked on the analysis of epidemics of COVID-19, Ebola, mpox, influenza, HIV, tuberculosis, cholera, dengue fever, and other infectious diseases. Dr. Longini is also working with the Department of Health and Human Services, the World Health Organization, the CDC and other public health organizations on mathematical and statistical models for the control of a possible bioterrorist attack with an infectious agent such as smallpox, and other natural infectious disease threats such as COVID-19, pandemic influenza or another coronavirus. Dr. Longini is author or coauthor of over 256 scientific papers and he has won a number of awards for excellence in research, including the Howard M. Temin Award in Epidemiology for “Scientific Excellence in the Fight against HIV/AIDS,” two CDC Statistical Science Awards for both “Best Theoretical and Applied Papers,” the CDC James H. Nakano Citation “for an outstanding scientific publications” the Science Magazine, one of the top 10 “Breakthrough of the Year” for 2015, Guinea Ebola ring vaccination trial, the Aspen Institute Italia Award for scientific research and collaboration between Italy and the United States, 2016, and the David A. Paulus Lifetime Achievement Award, College of Medicine, University of Florida. April 25, 2022. He is a Fellow of the American Statistical Association and a Fellow of the American Association for the Advancement of Science. Dr. Longini has Erdős number = 3.