A new analysis of blood samples from 24,000 Americans taken early last year is the latest and largest study to suggest that COVID-19 cases popped up in the U.S. in December 2019 – weeks before cases were first recognized by health officials.

During an interview with China Media Group, Dennis Carroll, chair for the leadership board of the Global Virome Project, said that the study results are credible and he hopes the United States can work with China to end the pandemic worldwide as soon as possible.