Commercial air travel's potential for spreading infection continues to cause handwringing among public health officials, as Tuesday's news of a jet-setting man with a rare and deadly form of TB demonstrates.
"We always think of planes as a vehicle for spreading disease," said Dr. Doug Hardy, an infectious disease specialist at UT Southwestern Medical Center in Dallas.
In the latest incident, reported by health officials on Tuesday, a Georgia man with extensively drug-resistant TB ignored doctors' advice and took two trans-Atlantic flights, leading to the first U.S. government-ordered quarantine since 1963.
The man, who officials did not identify, is at Atlanta's Grady Memorial Hospital in respiratory isolation. He was not considered highly contagious, and there are no confirmed reports that the illness spread to other passengers.
But his case illustrates ongoing concerns about the public health perils of plane travel, as well as the continuing problem of Typhoid Mary-like individuals who can almost be counted on to do the wrong thing.
The man decided to proceed with a long-planned wedding trip despite being advised not to fly. "There's always going to be situations where there is a lack of understanding and appreciation of responsibility to the community in a situation like this," said Dr. John Ho, an infectious diseases specialist at New York-Presbyterian Hospital/Weill Cornell Medical Center.
The incident also points out weaknesses in the system: The man was able to re-enter the United States, even though he said he had been warned by federal officials that his passport was being flagged and he was being placed on a no-fly list.
CDC officials said they contacted the Department of Homeland Security to put the man on a no-fly list, but it doesn't appear that was accomplished by the time he flew from Prague to Montreal and drove across the border from Canada.
A Transportation Security Administration spokesman could not immediately be reached for comment on Wednesday morning.
Challenges in coordination with airlines and in communicating with the media also have emerged, said Glen Nowak, a spokesman for the U.S. Centers for Disease Control and Prevention.
"This clearly is going to have some relevance to our pandemic influenza preparedness," Nowak said.
There have been several prominent disease-on-a-plane incidents in recent years.
Perhaps best known is severe acute respiratory syndrome, or SARS, which erupted in Asia in 2003. Over three months, CDC workers delayed on the tarmac 12,000 airplanes carrying 3 million passengers arriving from SARS-affected countries, and isolated people with SARS symptoms.
Last year, CDC officials worked with airlines and state health departments to track two infected airline passengers who may have helped spread a mumps epidemic throughout the Midwest.
And in March, a flight from Hong Kong was held at Newark International Airport for two hours because some of them reported feeling ill from a flu-like illness. They were released when it became clear they had seasonal flu, and not an avian variety.
Medical experts say TB is significantly less contagious than flu, SARS or other maladies that have led to airport alerts.
"This is not as easily transmissible as what we're concerned about with a flu pandemic," said Dr. William Schaffner, chairman of the department of preventive medicine at Vanderbilt University.
A more contagious bug, carried by a stubborn or evasive passenger, could be much more problematic, experts said.
Indeed, it's remarkable how rare are the incidents of serious contagions on planes, Ho noted.
"If you count the number of international flights there are on a daily basis, this is really a minuscule event" in terms of rate of occurrence, he said.
"However this underscores the interrelatedness of the global community. We can no longer escape things considered foreign" in this age of jet-travel, Ho said.