Some countries were not even aware that the regulations existed, his group reported. Others lacked laws vital to responding to outbreaks, such as those authorizing quarantines.

Changing those regulations would require “negotiations for years,” Dr. Wieler said, noting that the latest set took a decade to finalize. Instead, one of his committee’s major recommendations was to increase countries’ accountability for their obligations, including though a pandemic treaty and a periodic review of their preparedness that would involve other countries.

The independent panel also proposed creating an international council led by heads of state to keep attention on health threats and to oversee a multibillion-dollar financing program that governments would contribute to based on their ability. It would promise quick payouts to countries contending with a new outbreak, giving them an incentive to report.

“There’s only going to be the political will to create those things when something catastrophic happens,” said Dr. Mark Dybul, one of the panel members. These recommendations stemmed in part from his experience leading the President’s Emergency Program for AIDS Relief, known as Pepfar, and the Global Fund to Fight AIDS, Tuberculosis and Malaria, he said.

But Dr. Wieler, who led the other international review, said that in general, creating new institutions rather than focusing on improving existing ones could increase costs, complicate coordination and damage the W.H.O.

The recommendations of panels after global emergencies have sometimes been embraced. The Ebola outbreak of 2014 and 2015 led to the creation of the W.H.O.’s health emergencies program, aimed at boosting the agency’s role in managing health crises as well as providing technical guidance. A report released this month noted that the new program had received “increasingly positive feedback” from countries, donors and partner agencies as it managed dozens of health and humanitarian emergencies.

The W.H.O. before the Ebola outbreak and after it are “two different agencies basically,” said Dr. Joanne Liu, a former international president of Doctors Without Borders and a member of the independent panel. Dr. Liu was one of the W.H.O.’s most trenchant critics during the Ebola response, and she noted a “marked improvement” in how quickly the agency had declared an international emergency this time.