The Centers for Disease Control and Prevention has been told by the federal health officials to get the names and contact information of all passengers who boarded flights to the United States after Nov. 29 and who had been in southern Africa.
The directive applies to passengers who spent time in the Kingdoms of Eswatini and Lesotho, as well as the other countries of Africa, before flying to the United States. The airlines were told to give their names, addresses, phone numbers, email addresses, dates of birth and flight information.
The agency said that it was issuing the directive to prevent the spread of a communicable disease.
The White House banned travel from eight countries in southern Africa last week. The C.D.C. said late Tuesday night that it planned to toughen the testing and screening of people flying to the United States by requiring all international passengers to provide a negative result from a test taken within 24 hours of departure.
The October 25 order instructed airlines and aircraft operators to collect specific information from all passengers before boarding, retain it for 30 days, and send it to C.D.C. within 24 hours if requested.
The C.D.C. can give the information to the state and local health departments so they can monitor travelers for Covid, identify people who are sick, and direct those who are sick to isolation. They can use the information to make sure people get the right care.
The order applies to flights that left the United States on Monday. There were two flights that left from South Africa that day, a Delta Air Lines flight with more than 300 seats that was headed for Atlanta, and a United Airlines flight with more than 250 seats that was headed for Newark, N.J.
The flights landed in the United States on Tuesday morning. Two more United flights will leave South Africa for Newark on Wednesday, one from Cape Town and the other from Johannesburg.
Delta and United are the only carriers that offer direct flights between the countries covered by the C.D.C. order. There are three weekly flights between Atlanta and South Africa by Delta. There are five flights a week between Newark and South Africa. The flights between Cape Town and Newark will be resumed on Wednesday.
Both airlines have said that they are not planning to change their flight schedules in response to the ban on travelers from the region, which took effect on Monday and does not apply to American citizens or lawful permanent residents. The airlines plan to comply with the order.
Sixty-one people who arrived in the Netherlands on Friday aboard two flights that departed from South Africa tested positive for the Covid virus, including over a dozen who were carrying the new Omicron variant. More than 10% of the passengers tested had positive cases.
