The Centers for Disease Control and Prevention (CDC) has begun to ask airlines to share data on people traveling to and from the eight African countries subject to restrictions over the Omicron variant, Reuters reported on Wednesday. 

In a letter to airlines seen by Reuters, the CDC has asked that they turn over names and contact information for any travelers who in the last two weeks have been to Botswana, Eswatini, Lesotho, Malawi, Mozambique, Namibia, South Africa and Zimbabwe. These countries are subject to new U.S. travel restrictions as of Saturday after initial reports that the Omicron variant emerged from this region.

This request follows a hardening posture by the CDC as it hopes to reduce the chances of an Omicron outbreak in the U.S. 

On Oct. 25, weeks before the strain was first reported, the CDC had begun requiring all airlines to collect contact tracing information from all international air passengers without a requirement to turn over names. This requirement came into effect on Nov. 8. 

Following Omicron’s emergence, CDC Director Rochelle Walensky explained that her agency was looking into tightening the testing timeframe and adding a quarantine requirement in some instances. Walensky added that surveillance programs were being added at four major airports to test for COVID from specific international arrivals, as reported by Bloomberg News.

President Joe Biden downplayed the prospect of a new lockdown while urging Americans to receive their initial or booster doses of a COVID-19 vaccine. 

Currently, 74.7% of Americans have received at least one dose of a COVID-19 vaccine.

On Thursday, the White House is expected to unveil an updated COVID-19 strategy that will outline how it will handle the virus going into the winter season. This is likely to include new information on how it plans to deal with Omicron as well.