The pause in U.S.-bound flights of Afghan evacuees has been extended for at least seven more days due to a handful of diagnosed measles cases among refugees who recently arrived in the United States, the Pentagon said Monday.

The halt was announced Friday after the discovery of measles, federal officials said. On Monday, Pentagon press secretary John Kirby said there are now five diagnosed cases: four among Afghans who arrived at Dulles International Airport in the Washington, D.C., area; one at Fort Pickett in Virginia; and one at Fort McCoy in Wisconsin.

Military bases both in the U.S. and abroad are being used to process evacuees and house them until they can be placed in new homes.

Kirby said military officials are closely monitoring the refugees to see if more cases emerge. The five Afghans who were infected are being isolated and receiving medical care, and the Centers for Disease Control and Prevention is conducting contact tracing to determine if others should be quarantined, he said.

“We certainly are taking these cases seriously,” Kirby said. “That's why the CDC is involved and we've paused the flights coming in. We're observing all the CDC guidelines that need to be observed, and we'll be working very quickly on the appropriate immunization.”

Kirby said all Afghan evacuees arriving in the U.S. are required to be vaccinated for measles as a condition for their humanitarian parole. Immunizations have been taking place at domestic military bases, but Kirby said vaccinations will soon be given at overseas installations. 

The decision to pause the flights was made by U.S. Customs and Border Protection on the recommendation of the CDC. The development had American officials overseas Friday removing from planes Afghan families who already had struggled through a grueling, dangerous escape to safety after Kabul fell to the Taliban on Aug. 15. Afghans faced Taliban checkpoints and crushing crowds to enter the Kabul airport. A suicide attack at an airport gate killed 169 Afghans and 13 U.S. military members.

A government document viewed by The Associated Press last week said the halt would “severely impact” operations at Ramstein Air Base in Germany, one of the biggest transit sites. It noted many have been there more than 10 days and are increasingly fatigued.

Germany had set a 10-day limit for Afghans to stay at the U.S. base, but the time has appeared more as a guideline than a hard deadline. Some German politicians and media grumbled when some Afghans asked for asylum after reaching Germany.

Germany and Qatar, along with Italy, Spain, Kosovo, Kuwait and other countries, agreed to temporarily host U.S. processing sites for evacuees after Kabul fell, after allies initially balked over worries of getting stuck with U.S. security problems. Refugee groups have criticized the Biden administration for not bringing the Afghan evacuees to U.S. territory for screening.

Vaccination campaigns prevent major measles outbreaks in the United States, but measles can be a deadly disease for adults and children in countries where violence or other obstacles block immunization. Hundreds of Afghan children have died of measles in some recent years.

The Associated Press contributed to this report.