Anyone who doesn't wear a mask on public transport should be refused travel, the CDC said in stricter COVID-19 guidance

• The CDC "strongly recommends" all passengers and staff wear a face mask on public transport including airplanes, ships, trains, buses, and taxis, it said in guidance on Monday.
• "Conveyance operators transporting people should refuse boarding to anyone not wearing a mask," it said.
• The guidance is roughly in line with existing practices around the country, but it is stricter than any previous CDC guidance.
• The guidance comes more than four months after the World Health Organization said people "should be encouraged" to wear face masks on public transport.

Public transport operators in the US should refuse to allow anyone onboard without a mask, apart from in exceptional circumstances, the Centers for Disease Control and Prevention (CDC) said on Monday.

The CDC "strongly recommends" all passengers and staff wear a face mask on airplanes, ships, trains, buses, subways, ride-shares, and taxis, it said.

This includes waiting and boarding locations, such as airports, train stations, and ferry terminals.

The new guidance is roughly in line with existing practices around the country, but it is stricter than any previous CDC guidance.

Traveling on public transport increases the risk of spreading COVID-19 because people are in close contact, often for a long period of time, and may touch the same surfaces, the CDC said.

"Conveyance operators transporting people should refuse boarding to anyone not wearing a mask and require all people onboard, whether passengers or employees, to wear masks for the duration of travel."

The guidance comes more than four months after the World Health Organization said people "should be encouraged" to wear face masks on public transport.

In September, the CDC drafted an order that would have made its new guidelines compulsory, but it was blocked by the White House, two federal health officials told the New York Times on October 9.

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Staying 6 feet away from other passengers "may be difficult if not impossible" on buses and flights, the CDC said in its new guidance.

Public transport means that local transmission can quickly spread to other states and even other countries when infected people travel without wearing masks, according to the CDC.

"Broad and routine utilization of masks on our transportation systems will protect Americans and provide confidence that we can once again travel more safely even during this pandemic," the CDC said.

"Masks are most likely to reduce the spread of COVID-19 when they are widely used by people in public settings," the CDC said. Masks should cover both the nose and mouth, it added.

In June, the CDC recommended people cover their faces if they have to go out in public – but didn't make this a requirement.

Face masks were made compulsory on public transport in Germany in April. The UK, Spain, France, Italy, and Greece are among countries that have since introduced the same policy.