The U.S. Transportation Department was less prepared for the coronavirus pandemic because it failed to coordinate a national aviation preparedness plan for communicable disease outbreaks that a federal watchdog recommended in 2015 during the Ebola outbreak, a government oversight agency said.

The lack of such a plan undermined the ability of public health and aviation officials to coordinate their response to the Covid-19 pandemic and provide consistent guidance to airlines and airports, according to the Government Accountability Office released Tuesday.

“Not only could such a plan provide a mechanism for the public-health and aviation sectors to coordinate to more effectively prevent and control a communicable disease threat, it could also help minimize unnecessary disruptions to the national aviation system, disruptions that to date have been significant,” the GAO said in the report.

Under President Donald Trump and his predecessor, Barack Obama, the transportation department disagreed with the GAO’s recommendation that aviation needed its own communicable disease plan, the department said in a statement. Doing so “would risk an uncoordinated and disparate approach across different transportation modes and critical infrastructure sectors,” it said.

In addition, the Department of Health and Human Services has overall responsibility for communicable disease response and the Department of Homeland Security leads preparedness planning for all areas including transportation, the department said.