WASHINGTON, July 15 (Xinhua) -- U.S. Centers for Disease Control and Prevention (CDC) on Tuesday urged all Americans to wear masks to prevent the spread of COVID-19.

"Cloth face coverings are one of the most powerful weapons we have to slow and stop the spread of the virus, particularly when used universally within a community setting. All Americans have a responsibility to protect themselves, their families, and their communities," CDC Director Robert Redfield said in a statement.

CDC's appeal came days after U.S. President Donald Trump wore a mask publicly for the first time when visiting a hospital in Maryland.

For months, Trump and some senior administration officials have been criticized for being reluctant to advise the public to wear masks.

According to a new Hill-HarrisX poll, 44 percent of voters said people were less likely to wear masks when Trump did not set an example in wearing a mask to lower the spread of COVID-19.  ■