CHICAGO (NewsNation Now) — United Airlines and the Centers for Disease Control and Prevention are introducing a voluntary COVID-19 contact tracing effort for all international and domestic flights.

The airline announced its new program on Wednesday. Customers will have the option to provide their contact information to support the CDC’s efforts to stop the spread of coronavirus.

United plans to rollout the initiative in phases. Starting this week, the airline will collect contact information from travelers who voluntarily choose to do so for all international arrivals. Then, in the coming weeks, the airline will make the opt-in available for domestic and international outbound departures. The information collected and shared with the CDC includes customers’ email addresses, phone numbers and where they’re staying once they reach their destination.

Travelers can participate in the contact tracing program by filling out a form on United’s website, mobile app or at the airport.

“Collection of contact information from air travelers will greatly improve the timeliness and completeness of information for COVID-19 public health follow-up and contact tracing,” CDC Director Dr. Robert Redfield said in a statement.

United’s initiative follows a similar partnership announced this month between the CDC and Delta Air Lines. Delta’s voluntary program began Tuesday, allowing individuals traveling to the U.S. from an international location to provide information for contact tracing.