Important update: Healthcare facilities
CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more
Given new evidence on the B.1.617.2 (Delta) variant, CDC has updated the guidance for fully vaccinated people. CDC recommends universal indoor masking for all teachers, staff, students, and visitors to K-12 schools, regardless of vaccination status. Children should return to full-time in-person learning in the fall with layered prevention strategies in place.
The White House announced that vaccines will be required for international travelers coming into the United States, with an effective date of November 8, 2021. For purposes of entry into the United States, vaccines accepted will include FDA approved or authorized and WHO Emergency Use Listing vaccines. More information is available here.
Travel requirements to enter the United States are changing, starting November 8, 2021. More information is available here.

COVID-19 Forecasting: Background Information

COVID-19 Forecasting: Background Information

Why COVID-19 Forecasting Is Important

CDC is responding to a pandemic of coronavirus disease 2019 (COVID-19) caused by a new 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, hospitalizations, and cases will help inform public health decision making by projecting the likely impact of the COVID-19 pandemic in coming weeks.

Bringing Together Forecasts for COVID-19 Deaths, Hospitalizations, and Cases in the United States

CDC works with partners to bring together weekly forecasts based on statistical or mathematical models that aim to predict:

  • National and state numbers of new and total COVID-19 deaths per week for the next 4 weeks.
  • National and state numbers of new COVID-19 hospitalizations per day for the next 4 weeks.
  • National, state, and county numbers of new COVID-19 cases per week for the next 4 weeks.

Forecasting teams predict numbers of deaths, hospitalizations, and cases using different types of data (e.g., COVID-19 data, demographic data, mobility data), methods, and estimates of the impacts of interventions (e.g., social distancing, use of face coverings). These forecasts are 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 near future.

An “ensemble” forecast combines each of the independently developed forecasts into one aggregate forecast to improve prediction over the next 4 weeks.  This article, Ensemble Forecasts of Coronavirus Disease 2019 (COVID-19) in the U.S.external icon describes the “ensemble” forecast methodology and its usefulness as a real-time tool to help guide policy and planning.

Weekly forecasts submitted to CDC are posted on these websites:

Previous forecasts are available at:

Forecasts on COVID data tracker