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Tuberculosis is in the headlines as 31-year-old Atlanta lawyer Andrew Speaker is being treated in isolation at a Denver hospital.
The story is raising questions about tuberculosis. Here are 17 questions and answers.
What is tuberculosis?
Tuberculosis (TB) is an infectious disease caused by a bacterium that spreads through the air, usually through coughing.
How common is tuberculosis?
According to the World Health Organization, more than 8.8 million people worldwide are infected with tuberculosis, and almost 1.6 million people per year die from tuberculosis.
There are about 14,000 cases of tuberculosis every year in the U.S., according to Carol Dukes Hamilton, MD, an infectious disease specialist at Duke University Medical Center and the medical director of North Carolina's tuberculosis control program.
"TB continues to be a really major problem in the world. It's huge," Hamilton says.
"The most common thing people say is, 'TB? I thought it was gone.' It's really not gone. And it can surge. It can come back. We don't want to be alarmist, but we have to continue to pay attention."
If millions of people have tuberculosis, why is Speaker's case different?
Unlike most tuberculosis patients, Speaker has extensively drug-resistant tuberculosis (XDR TB). That means he's already unsuccessfully tried the first and second preferred drug treatments.
Speaker's case also garnered instant attention when the CDC ordered him into isolation for medical treatment and alerted the public about his travels so that passengers on his transatlantic flights could get TB tests.
If tuberculosis is contagious, why don't Speaker's wife or friends have tuberculosis?
"It sounds like he's probably somebody who was in a pretty early state of TB," says Hamilton, cautioning that she isn't personally familiar with Speaker's case. ?
"He wasn't horribly sick because he felt like going on his honeymoon and he was what's called 'smear negative.' In those situations, often people aren't very infectious," says Hamilton.
"It's also possible that he's only recently become contagious, in which case we won't know that his wife has been exposed for a few weeks, because it would take about eight weeks for her body or others who were exposed to him to demonstrate that they've even been exposed to him," Hamilton says.
"It takes about eight weeks for the body to say, 'Hey, there's something here I need to deal with it, need to make antibodies, need to react.' So it may still be too early to know the people around him have been affected," says Hamilton.
What is "smear-negative" TB?
"What that means is that when he coughed up a specimen to give to the doctors to test for TB, the laboratory looked under the microscope they didn't see any TB bacteria. It was only when [the sample] was cultured that then they figured out, 'Oh, there really is TB here' and then it took some weeks to figure out it was drug resistant," says Hamilton.
In contrast, smear-positive TB patients "have so much TB in their lungs that when the laboratory looks directly into the microscope, they can see the bacteria right there. Those people tend to be a lot more infectious or contagious to others than someone who really has disease but doesn't yet have enough built up that they're really coughing out a whole lot at a time."
When TB bacteria keep growing, eventually "you can see it under a microscope, and that's associated with easily infecting other people," Hamilton says.
Speaker has said he felt fine and had been exercising with no obvious symptoms. How is that possible? Is that because he was in the early stages?
"That's definitely how that's possible," says Hamilton.
She recalls the case of a surgeon who operated on a patient who was later found to have TB and who was also exposed to TB while working in Africa.
"He had TB," Hamilton says. "In talking with him, he said, 'Well, when I do my five-mile runs, I might have noticed I was slightly more out of breath than usual.' In other words, [he was] healthy, working, running, totally fine," Hamilton says.
"I feel quite certain that as time went on, he would have become ill. He just wasn't quite there yet," she says. "It goes to show that this disease can kind of sneak up on people."
Do most TB patients have symptoms, and what are tuberculosis symptoms?
"That's what we think, that most people eventually have some kind of symptom," says Hamilton.
When people get sick with tuberculosis, their?symptoms may include fever, night sweats, cough, appetite loss, weight loss, bloody phlegm, and loss of energy.
Can anyone catch TB?
"Yes, if they are in close association with someone who has tuberculosis," says Hamilton.
"That means not just walking past them in Hartsfield Airport in Atlanta," she adds.
"Usually it's sharing an office with them, living in the same household with them, being in a homeless shelter with them and sleeping in a bed next to them -- time with that person."
"Tuberculosis is around," Hamilton says. "Does that mean people should be nervous about going to the mall? No. It's not horribly common. Now, if people travel to countries where there's still a lot of TB, then your risk is increased."
How did the patient get infected with TB?
That's not yet known.
The patient's father-in-law is a tuberculosis expert at the CDC. Could the patient have gotten TB from his father-in-law?
The patient's father-in-law is Robert Cooksey, a research microbiologist in the CDC's division of tuberculosis elimination.
In a statement issued on May 31, Cooksey says he has never had TB and that his son-in-law's XDR TB didn't come from him or CDC labs.
What tests determine whether a person has TB? Are those tests safe if you are pregnant or are trying to conceive?
"The tests are safe whether you're pregnant or are trying to ," says Hamilton.
"The most common test is called the tuberculin skin test, or PPD. That's where a tiny, killed piece of TB is put right under the skin and you see if your body reacts to it or not. There's a newer blood test called QuantiFERON that tells us about the same information. That test not available all over the place," Hamilton says.
Since tuberculosis grows slowly, people get a follow-up test about two to three months after their initial test.
How is TB treated?
"Ninety-five percent of people will respond to the combination of the four first-line drugs -- isoniazid, rifampin, pyrazinamide, ethambutol," Hamilton says.
Drug-resistant tuberculosis is rarer and XDR TB, which Speaker has, is rarer still, affecting "a few cases per year" in the U.S., Hamilton says. ?
"But in other countries, it's really increasing," Hamilton says. "So it is true that it's not that far away. Our TB program budgets have been cut every year, and so we get less and less able to respond to this sort of thing."
Hamilton also warns that "if our regular TB cases aren't managed appropriately and aggressively, they can become drug resistant. While we don't want to engender panic, it's a real concern." ?
What about surgery?
Surgery may be done to remove damaged lung areas if drug treatments fail for XDR TB.
Speaker's treatment in Denver may last for months. That's how long it may take for doctors to find out if his tuberculosis responds to any antibiotic treatments.
If months of antibiotic treatment do not suffice, Speaker may also get surgery to remove parts of his lung affected by tuberculosis.
But it's too soon to know if Speaker will need that surgery, says Marvin Pomerantz, MD, director of the Center for the Surgical Treatment of Lung Infections at the University of Colorado at Denver Health Sciences Center.
Pomerantz tells WebMD if Speaker gets the surgery, it would be done at the University of Colorado at Denver Health Sciences Center.
In describing the surgery, Pomerantz says he "wouldn't call it a last resort. I'd call it part of the overall treatment of the difficult cases of tuberculosis," with more antibiotic treatment after the operation.
The surgery "should be done only in specialized units that are used to dealing with these particular problems," says Pomerantz.
What transatlantic flights did Speaker take?
According to the CDC, he flew on two transatlantic flights in May:
What should passengers on those flights do?
Call the CDC at 800-CDC-INFO for information on tuberculosis testing.
Passengers likely to be at highest risk for potential tuberculosis transmission during those flights were sitting in Speaker's row and in the two rows in front or behind him, notes CDC?Director Julie Gerberding, MD, MPH.
Gerberding says the CDC?has been in touch with 74 U.S. citizens and residents on the Air France/Delta flight, including all 26 passengers who were believed to be sitting in the high-risk rows around Speaker's seat.
Canadian authorities have identified the 28 passengers seated in the high-risk rows around Speaker on the Czech Airlines flight, says Gerberding.
Those passengers -- and anyone else on those flights -- will be put in touch with local health officials in their city or state for tuberculosis testing. Since tuberculosis grows slowly, any initial tests that show tuberculosis would probably stem from infection before the flights. Follow-up tests in about two months will indicate whether or not any of those travelers got tuberculosis on those flights.
"It's hopeful we're not going to see a lot of exposure because he probably wasn't terribly contagious," Hamilton says.
Were those the only flights he took on his honeymoon?
No. The patient and his wife also took several shorter flights from France to Greece to Rome and to Prague, Czech Republic.
However, the CDC and World Health Organization consider the risk of infection to travelers on flights lasting less than eight hours to be low. Each of those European flights lasted less than eight hours.
A full list of those flights is posted on the CDC's web site.
Is it rare for a TB patient to
be put in isolation?
The federal isolation order is rare, "but every state has public health
laws," Hamilton says.
Hamilton notes that in North Carolina, where she directs the states TB control program, "most people are happy to follow the advice to stay home [and not travel] until we are sure that you're not infectious."
"But there are some people who don't want to do that, in which case we would issue an isolation order." Most patients comply with isolation orders, but if they don't "we can compel them to go to prison until they are no longer infectious and they finish their TB treatment."
Such cases are very rare, Hamilton notes. "We don't like to do that," she says. "But it's better to do that than to expose a lot of people."
In a CDC news conference, Gerberding said that while the federal isolation order is still in place for Speaker, she "wouldn't be surprised" if that order is lifted "at some point in the future."