WASHINGTON (Reuters) — The U.S. Centers for Disease Control and Prevention on Friday said people who are fully vaccinated against COVID-19 can safely travel at “low risk” after the agency had held off for weeks on revising guidance that discouraged all non-essential trips.

The announcement lifting the agency’s guidance that all Americans should avoid non-essential travel should be a shot in the arm for a U.S. travel industry still significantly struggling since the COVID-19 crisis began in early 2020. The new CDC guidance specifically greenlights vaccinated grandparents getting on airplanes to see grandchildren.

CDC Director Dr. Rochelle Walensky said the latest guidelines are a step closer toward normalcy, but the nation still has a “lot of work to do.”

“It’s our responsibility at the CDC to look at the risks. Traveling would be low risk if you are fully vaccinated, Dr. Walensky said during the White House COVID-19 Response Team briefing Friday. “There are 64,000 new COVID cases today and our numbers continue to increase. I still worry that with 80% of the population unvaccinated we have a lot of work to do to control this pandemic.”

A group representing major U.S. airlines including American Airlines, Delta Airlines, United Airlines Southwest Airlines and other trade groups on March 22 had urged the CDC to immediately update its guidance to say “vaccinated individuals can travel safely.”

The CDC said grandparents that have been fully vaccinated can fly to visit grandkids without getting a COVID-19 test or self-quarantining as long as they follow CDC advice for traveling safely.

But the administration is not lifting restrictions that bar most-non U.S. citizens from the United States who have recently been in China, Brazil, South Africa and most of Europe. It is also keeping requirements that nearly all international U.S. air visitors getting a negative COVID-19 test before traveling to the United States.

The CDC did not revise guidance for non-vaccinated people.

“We don’t recommend travel for non-vaccinated people. If you must travel limit it to only essential travel. This update is only for vaccinated Americans, which is only about 20 percent of the population,” Dr. Walensky said.

The CDC’s new guidance says fully vaccinated people do not need COVID-19 tests before international travel unless it is required by the international destination and vaccinated people returning from foreign travel do not need to self-quarantine after returning to the United States, unless required by state or local authorities.

The CDC had repeatedly declined in recent weeks to change the guidance and repeated it was still discouraging all non-essential travel because of a concern about new variants.

Many Americans have not been heeding the CDC’s advice. The Transportation Security Administration screened 1.56 million people at U.S. airports, just below Sunday’s 1.57 million, which was the highest daily total since March 2020. The last time the number of airport passengers screened was below 1 million was March 10.

The Biden administration has taken steps to reduce international travel and mandated masks in nearly all forms of public transit. The administration is not eliminating any mask rules.