The United States is unprepared for a potential flu pandemic, Centers for Disease Control and Prevention Director Dr. Robert Redfield said in a House Appropriations Committee hearing Thursday. The next pandemic could be deadlier than the coronavirus and may come while the nation is still handling its response to the current pandemic, potentially as soon as this fall, Redfield said.

A flu pandemic is distinct from the seasonal flu in that it is caused by a new strain of the influenza virus not previously faced by humans, making it far more dangerous due to a lack of immunity. The most recent flu pandemic, H1N1 or the “swine flu,” hit in 2009 and may have killed more than 500,000 people worldwide. The novel coronavirus has killed about 109,000 in the United States and 380,000 across the globe.