The Center for Infectious Disease Research and Policy at the University of Minnesota seeks to help planners envision what might happen later in 2020 or in 2021. SARS-CoV-2, the virus that causes COVID-19, is “the worst global public health crisis in over 100 years…its future course is still highly unpredictable.” The best comparative model is influenza, which created at least eight global pandemics since the early 1700s. “Based on the most recent flu pandemics, COVID-19 will likely last 18 to 24 months.”
The pandemic “likely won’t be halted until 60-70% of the population is immune.” Depending on control measures and whether a vaccine is developed sometime in 2021, three scenarios are offered:
- Peaks and Valleys: the first wave in spring 2020 is followed by a series of smaller waves that gradually diminish sometime in 2021, which may vary depending on mitigation measures;
- Fall Peak: the first wave in spring 2020 is followed by a larger wave in fall or winter 2020, and one or more smaller waves in 2021 (a pattern similar to the 1918-1919 flu pandemic);
- Slow Burn: the large spring 2020 wave is followed by ongoing transmission and case occurrence, but likely would not require reinstituting mitigation measures. “Authorities should plan for the worst-case scenario (#2), including no vaccine availability or herd immunity.” Concrete plans should be developed that include triggers for reinstituting mitigation measures, and risk communication messaging should stress that “this pandemic will not be over soon, and that people need to be prepared for possible periodic resurgence of disease over the next 2 years.”
Note: Also see Part 2: Effective COVID-19 Crisis Communication (May 6, 11p).