The United States was too slow in its coronavirus response and banning travel from Europe, one of several steps officials should have taken sooner to curtail the fast-spreading virus.

Dr. Anne Schuchat, the second highest ranking official at the Centers for Disease Control, in an article published Friday said the U.S. failed to understand quickly enough how the virus was spreading from Europe.

“The extensive travel from Europe, once Europe was having outbreaks, really accelerated our importations and the rapid spread,” Schuchat told The Associated Press. “I think the timing of our travel alerts should have been earlier.”

President Trump has repeatedly touted his decision on Feb. 2 to halt travel from China, where the coronavirus first emerged in the city of Wuhan late last year. However, an order limiting travel from Europe did not officially occur until March 11 — one of the government’s biggest errors, according to Schuchat.

In the month ahead of the European travel ban, nearly 2 million people from Italy and other nations arrived in the U.S., according to a new article released by the CDC, which is responsible for tracking and disease prevention.

“We clearly didn’t recognize the full importations that were happening,” said Schuchat.

Limited testing and the slow implementation of social distancing are also key factors in the acceleration of cases in the United States, the article continued. Mass gatherings in February, including a scientific meeting in Boston, New Orleans’ annual Mardi Gras celebration and a Georgia funeral, resulted in dozens and dozens of Americans infected.