Special Report

How Long It Took for COVID-19 Cases to Double in Every State

The United States started 2021 just about the same way it ended 2020 — by setting dismal records amidst the COVID-19 pandemic. It took 292 days for the United States to reach its first 10 million cases, and just 54 more days to double that number, with the U.S. hitting 20 million cases on Jan. 1, 2021. As of Jan. 13, there have been over 23.2 million cases confirmed nationwide.

To find how long it took for the recent levels of COVID-19 cases to double in each state, 24/7 Wall St. used data compiled from state and local health departments. For each state, 24/7 Wall St. found the date on which the number of cumulative confirmed COVID-19 cases was half or nearly half the number as of Jan. 12. We then also found the date that represents the previous doubling period.

The surges in infections since the fall have been blamed on small gatherings where family members not of the same household and friends were sitting too closely together in confined rooms, driving up overall infections in their communities and across the country.

It took between a month to almost four months for the number of coronavirus infections to double in each state. Cases doubled fastest are spread nationwide.

For example, Florida, a Southern state with the third-largest population in the country, doubled its COVID-19 cases in 88 days, the third longest period of time. California, a West Coast state and the most populous, doubled its number of infections in 36 days, the second shortest period. 

 The rollout of two vaccines has provided some hope. Every day, thousands more people are getting the vaccine, but life may not go back to pre-COVID-19 normalcy soon — here are 17 non-obvious ways the pandemic has changed our lives.

Click here to find out how long it took for COVID-19 cases to double in every state

Using data from state and local health departments, 24/7 Wall St. reviewed the cumulative confirmed COVID-19 cases as of Jan. 12 in every state. We identified for every state the dates on which confirmed cases were half or almost  half the number of confirmed cases on Jan. 12 to determine how many days it took for COVID-19 cases to double in every state.

For example, it took 109 days for the cumulative number of coronavirus infections to double in Hawaii as of Jan. 12, 2021. The date 109 days ago was Sept. 25, 2020. We then identified the date on which confirmed cases were half or close to half of cumulative COVID-19 cases on Sept. 25.

Population figures came from the U.S. Census Bureau’s 2019 American Community Survey 1-Year Estimates.