DENVER - Federal health officials stand by their quarantine of an Atlanta lawyer they believed had a dangerous form of tuberculosis, even though new tests show he has a less severe form of the disease.

"The public health actions that CDC took in this case, and are continuing to take, are sound and appropriate," said Dr. Mitchell Cohen of the Centers for Disease Control and Prevention.

The lawyer, Andrew Speaker, said the CDC's actions were anything but appropriate when he became the center of an international health scare in May, when officials said he had traveled to Europe and back with an extremely drug-resistant form of TB.

The announcement Tuesday from Speaker's doctors raised immediate questions about the accuracy of the diagnosis by U.S. government health officials who had made Speaker the subject of the first federal quarantine order since 1963.

Cohen, speaking at a news conference here, said the public health response should be the same to both forms of drug-resistant TB.

Speaker said in a statement that the new diagnosis relieved him.

"The truth is that my condition is just the same as it was back in early May, long before there was a huge health scare, and back when I was allowed to carry on my daily life and was told I was not a threat to anyone," said Speaker, who was first told two weeks ago that he didn't have extensively drug resistant TB, or XDR-TB, as testing continued.

He also gave a harsh critique of the government's handling of the case: "In the future, I hope they realize the terribly chilling effect they can have when they come after someone and their family on a personal level. They can in a few days destroy an entire family's reputation, ability to make a living and good name."

In an interview with CNN's Anderson Cooper Tuesday night, he said he believed the CDC needed to apologize.

"I think they owe apologies to the people that they scared," he said.

He continued: "They created a huge international panic. They scared, you know, millions of people around the world."

The news that he has a more treatable form of TB means he may avoid surgery and has a much better chance for a cure.

"These new test results are good news for Mr. Speaker. His prognosis has improved," said Dr. Charles Daley, who is treating Speaker at National Jewish Medical and Research Center. "We now have more effective medications available to fight his disease and may be able to treat him successfully without surgery."

It was also good news for any airline passengers who were alarmed to find that Speaker was on their trans-Atlantic flights when he flew to Europe for his wedding and honeymoon even though health officials in Atlanta had advised him not to do so.

The CDC won't know until late July or August whether anyone may have contracted the disease from the 31-year-old Speaker, Daley said. But if they did, they would be easier to treat.

For the past month, Speaker has been isolated at the Denver hospital, which specializes in treating TB and other respiratory diseases. His bride, Sarah, has paid regular visits.

Speaker was found in May to have XDR, based on an analysis of a sample taken in March by the CDC. The strain is rare, extremely difficult to treat and is a growing public health threat.

But later tests in Denver indicate Speaker's TB is a more treatable form of the disease, called multidrug-resistant TB. And the CDC's own retesting of its original sample from Speaker now matches the results in Denver. Multidrug-resistant TB can be treated with some antibiotics that the more severe form resists.

"I don't think we'll ever know why this happened," Daley said.

The CDC's Cohen explained that reading the test results is not black and white.

It's possible for a couple of types of TB to be in one sample, and in one patient, he said. That is one of several possible explanations for why CDC might have found XDR, while subsequent test results show MDR, Cohen said. The sample could have been contaminated or two specimens could have become mixed, he said.

The CDC's diagnosis of XDR-TB was a key factor cited by CDC chief Dr. Julie Gerberding in issuing a quarantine order against Speaker.

When he flew to Greece to be married in May, he was believed to have only MDR-TB. Speaker ignored federal health officials' warnings to get medical help in Europe and not to get on an airplane. Instead, he and his wife flew to Canada and crossed the border into the United States even though his name was on a no-fly list given to border guards.

He was briefly placed under federal quarantine and later sent to the hospital in Denver. The case prompted a hunt for passengers on the cross-Atlantic flights taken by Speaker so they could be tested for the disease.