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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 [whether] 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
[and] 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 -- [spending] 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
[conceive]," 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 Hospital. 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:
Air France flight 385
(Delta co-share flight 8517): Departed Atlanta on May 12, arrived in
Paris on May 13
Czech Airlines flight 0104:
Departed Prague, Czech Republic on May 24, arriving in Montreal on the
same day
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."
SOURCES: World Health Organization: "Tuberculosis." Carol Dukes
Hamilton, MD, infectious disease specialist, Duke University Medical
Center; medical director, North Carolina Tuberculosis Control Program.
National Jewish Medical and Research Center: "About Tuberculosis."
Julie Gerberding, MD, MPH, director, CDC. Marvin Pomerantz, MD,
director, Center for the Surgical Treatment of Lung Infections at the
University of Colorado at Denver Health Sciences Center.
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