CDC Updated (May 28th) COVID-19 Forecasts

#15,302

For the 7th week running the CDC has released an updated COVID-19 forecast of deaths in the United States, this time incorporating a record 20 models in its analysis (up from 16 last week). 

While forecast models are useful, particularly for showing trends, they do need to be taken with a grain of salt.

In mid-April, when there were fewer than 25,000 COVID-19 deaths in the United States, a limited number of forecast models (n=5) suggested we might top out at between 60,000 and 70,000 deaths by the end of summer.  By mid-May that number has increased to somewhere around 90,000 deaths (ensemble average) by June 1st.

Conditions - and assumptions - change over time, and today we are either at or very near 110,000 COVID-19 related deaths.

These models are based on assumptions of varying degrees of social distancing by the public, and that is a variable that can change abruptly. The impact of the nationwide protests and vigils for George Floyd, the reopening of restaurants, beaches, and casinos, and the general reduction of mask wearing and social distancing by the public are all factors that can change the course of the COVID-19 outbreak.

This week's summary dispenses with their previous 4-week `ensemble' estimate of U.S. deaths (although eyeballing the chart, it looks close to 130,000 deaths), and instead provides a (very) wide range of model estimates (118,000 - 143,000).

Some excerpts from this week's update follow:

COVID-19 Forecasts: Cumulative Deaths

Updated June 4, 2020

Interpretation of Cumulative Death Forecasts

• This week CDC received 20 individual national forecasts.

• This week’s national ensemble forecast suggests that the number of newly-reported COVID-19 deaths per week will continue to decline. It predicts between 118,000 and 143,000 cumulative COVID-19 deaths by June 27.

• Ensemble forecasts indicate that the rate of newly-reported deaths will vary among the states. In some states, cumulative deaths will increase at roughly the same rate as they have in recent weeks, while other states are likely to experience only a small number of additional deaths from COVID-19.

National Forecast

• These forecasts show cumulative reported COVID-19 deaths since February and forecasted deaths for the next four weeks in the United States.
• Models make various assumptions about the levels of social distancing and other interventions, which may not reflect recent changes in behavior. See model descriptions below for details.

State Forecasts

State-level forecasts show observed and forecasted state-level cumulative COVID-19 deaths in the US. Each state forecast uses a different scale, due to differences in the numbers of COVID-19 deaths occurring in each state.

Forecasts fall into one of two categories

• The Auquan, CAN, ERDC, GA_Tech, Geneva, Imperial, ISU, LANL, MIT, MOBS, PSI, SWC, UA, UCLA, UMass-MB, and UT forecasts assume that existing control measures will remain in place during the prediction period.
• The Columbia, CovidSim, GT_CHHS, JHU, and YYG forecasts make different assumptions about how levels of social distancing will change in the future.

Download state forecasts pdf icon[12 pages]
Download forecast data excel icon[1 sheet]

Why Forecasting COVID-19 Deaths in the US is Critical

CDC is responding to a pandemic of coronavirus disease 2019 (COVID-19) caused by a novel coronavirus, SARS-CoV-2, that is spreading from person to person. The federal government is working closely with state, tribal, local, and territorial health departments, and other public health partners, to respond to this situation. Forecasts of deaths will help inform public health decision-making by projecting the likely impact in coming weeks.

What the Forecasts Aim to Predict

Forecasts based on statistical or mathematical models aim to predict changes in national- and state-level cumulative reported COVID-19 deaths for the next four weeks.

Forecasting teams predict numbers of deaths using different types of data (e.g., COVID-19 data, demographic data, mobility data), methods (see below), and estimates of the impacts of interventions (e.g. social distancing, use of face coverings).

Working to Bring Together Forecasts for COVID-19 Deaths in the US

CDC works with partners to bring together weekly forecasts for COVID-19 deaths in one place. These forecasts have been developed independently and shared publicly. It is important to bring these forecasts together to help understand how they compare with each other and how much uncertainty there is about what may happen in the upcoming four weeks.

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