I'm Dr. John Iskander.
Welcome to CDC Beyond the Data.
I'm here today with Dr. Sarita Shah.
Sarita, today we heard at Public Health Grand Rounds
about multidrug-resistant tuberculosis.
Could you remind our audience about some
of what I call the basic complexities of tuberculosis
as an infectious disease?
Sure. Thanks, John.
Tuberculosis is an ancient infectious disease and it's been
around for hundreds of years.
One of the major challenges
with tuberculosis is making an accurate diagnosis of TB.
Even in the best circumstances, the current tests we have
for diagnosing TB require testing sputum
to find the bacillus, and that can be missed
in up to half of all cases.
Treatment for drug-susceptible TB uses a standard four drug
antibiotic regimen and takes about six months.
It's very effective if taken correctly-prescribed
correctly-and completed,
and cure rates can approach about 95 percent.
For drug-resistant TB, it's much more complicated.
The treatment requires use of four or five drugs for up
to two years and the drugs have many more side effects,
they cost a lot more, and they don't work as well
as the drugs we have for susceptible TB.
We have some complications involved in both diagnosing
and treating multidrug-resistant, or MDR, TB.
How big a problem is MDR TB in the world today?
MDR TB is a important public health problem
and an growing problem.
There are an estimated half a million cases of MDR TB
that occur worldwide each year.
One of the challenges with MDR TB, as we've discussed,
is the diagnosis of MDR, and of the half a million cases,
less than 20 percent are actually diagnosed.
So, a great global public health burden, and as you said,
some complexities in diagnosing and treating it.
Is there any hope on the horizon?
Are there some new tools that are available?
There is hope and, for the first time in decades,
we have revolutionary tests that can diagnose MDR TB faster,
in just hours in the laboratory, and they're not as complicated.
They pretty much require the same things you need
to do a sputum smear.
And this test is called the GeneXpert.
It works in about two hours to give you a diagnosis
of drug-resistance, and this has the great potential
to provide a diagnosis to patients much faster
than the tests we have now which can take weeks and months.
The challenge with the new diagnostics, like Xpert
or others, is it's part of a health system,
and the test itself can give you results in about two hours,
but the entire system around the test needs to be working well.
Patients need to come to their providers in a timely way,
they need to be close to centers that have this test,
the test results then need to be fed back
to providers in a timely way.
So the whole system needs to be working well
to really realize the full potential
of the new diagnostic tests.
We also have new drugs for MDR TB
for the first time in decades.
We heard about some of those today.
Bedaquiline is the first new TB drug approved
in over a generation here by the FDA, and it offers great promise
because it has fewer side effects
and does not require injections
like the current drugs we have for MDR TB.
So we have some new, new hope for more rapid diagnosis,
new hope for more effective therapy.
What needs to be done on the global stage to really,
for us to really reap the benefits of these new tools?
I think, as we touched on for diagnostics,
health system strengthening is really going to be at the core
of realizing the potential of the new diagnostics
and the new drugs, and also in preventing emergence
of more drug-resistant TB cases.
I think one of the fundamental principles
in drug-resistant TB is prevention and that begins
by ensuring that cases
with drug-susceptible TB are diagnosed and supported
in completing treatment
so we don't get more cases of drug-resistant TB.
But then, if there are cases of drug-resistant TB,
which are sure to exist, infection control and prevention
of transmission are critical.
And this area has really been neglected for decades
and is finally now receiving the attention
that has long been needed.
Infection control is not very sexy.
It requires things like opening windows and wearing face masks
to protect health care workers and other patients,
but it really is fundamental
to preventing this epidemic from expanding.
I think realizing the potential
of the new drugs will require a major global effort
and there are efforts underway,
as we heard today from Dr. Lienhardt.
I think it will require a concerted effort to bring drugs
to patients, to reduce the cost of drugs, and to provide drugs
in a supported environment
where patients will receive continuous drug supply
and will be supported to complete treatment until the end
of the lengthy course and prevent emergence
of further resistance.
So, we have new technologies, we have new drugs, but we also need
to go back to the basics
of infection control and case management.
Thank you very much.
This has been CDC's Beyond the Data.
Please join us again next month.