COVID-19 was first identified in December 2019 and was declared a global pandemic within months. While research on the disease and its outcomes is still in relatively early stages, the pandemic set off an unprecedented level of scientific collaboration and discovery.
Photo by Alisha Jucevic, Reuters.
We began forecasting the trajectory of the COVID-19 pandemic in early 2020 to help hospitals and policymakers plan how to allocate resources. Now, we estimate cases, deaths, and disability due to COVID-19 as part of the Global Burden of Disease study.
Our research supports the need for annual vaccines. While immunity after an infection is initially strong, it begins to drop after about 6 months and can provide as little as a third of its previous protection after a year.
On average, long COVID lasts nine months for someone who was hospitalized for their illness and four months for someone who was not.
15% of those with long COVID symptoms three months after becoming infected with COVID continued to experience symptoms even at 12 months.
However, there were trade-offs that came with those decisions. While states with more restrictions did not experience worse economic outcomes, they did have lower rates of employment and lower student test scores.
The latest on COVID-19
IHME researchers share the latest findings and key takeaways with our Global Health Insights series.
In December 2022, we paused our regular COVID-19 updates. Past estimates remain publicly available in our interactive data visual.