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Frequently
asked questions What is
TB? How
does TB spread? What
is TB infection? What
is TB disease? What if I
have been vaccinated with BCG? What
are the symptoms of TB? How
can I get tested for TB? Can TB
be cured? How
is TB disease treated? What
are the side effects of TB drugs? Why
do I need to take TB medicine regularly? How
can I keep from spreading TB? What
if I have HIV infection? What
is multidrug-resistant TB (MDR TB)? What
is the exact technical difference between multi drug resistant TB and
extensively drug resistant (XDR) TB? Is
any treatment available for XDR-TB now or in the near future? Has
there been a recent WHO survey and/or report on XDR-TB in India? Is
this rise in XDR-TB in any way linked to co-infection with HIV and
cross-reactions of anti-HIV and anti-TB drugs? Even
if not, how will this impact the HIV epidemic in the Region? Do
countries have the capacity to diagnose XDR cases in time?
What is TB?
TB, or tuberculosis, is by a bacterium called
Mycobacterium tuberculosis. The bacteria can attack any part of the body, but
most frequently attacks the lungs. TB should be suspected when a person has
cough for three weeks or more.
 How does TB spread?
TB of the lungs and throat is infectious. When a person
with TB of the lungs coughs or sneezes, TB bacteria spread into the air.
People nearby may breathe in these bacteria and become infected. When a
person breathes in TB bacteria, the bacteria settle in the lungs and begin to
grow. From there, they may move through the blood to other parts of the body,
such as the kidney, spine or brain.
What is TB infection?
Most people who breathe in TB bacteria become infected. In
most cases, the body is able to fight the bacteria to stop them from growing.
The bacteria become inactive, but since they remain alive, can become active
later.
People who are infected with TB do not feel sick, do not
have any symptoms, and cannot spread TB. But they could develop TB disease at
some time in the future.
What is TB disease?
Some people develop TB disease soon after becoming
infected when TB bacteria begin to multiply rapidly, before their immune
system can fight back. Other people may get sick later, when their immune
system becomes weak for some reason.
TB in other parts of the body, such as the kidney or
spine, is usually not infectious.
Babies and young children often have weak immune systems.
People infected with HIV have very weak immune systems. Other people who have
weak immune systems, are those who have the following conditions:
 diabetes
mellitus
silicosis
cancer
of the head or neck
leukemia
or Hodgkin's disease
severe
kidney disease
low
body weight
certain
medical treatments (such as corticosteroid treatment or organ
transplants)
What if I have been immunized
with BCG?
BCG is a vaccine for TB. This vaccine is given to infants
and small children. BCG vaccine protects against the severe, life-threatening
forms of TB such as TB meningitis and miliary TB in childhood. However, it
does not protect people from TB later in their life.
What are the symptoms of TB?
The most common symptoms of TB are:
cough
fever, especially rising in the evening
night sweats
chest pain
weight loss
loss of appetite
coughing up of blood.
How can I get tested for TB?
The best way to get tested for lung TB is by getting your
sputum examined. Germs of TB or TB bacilli can be seen through a microscope.
Three samples of sputum should be examined for accurate diagnosis. This
facility is available at all public health facilities in your country.
Can TB be cured?
Yes. TB can be cured if the full course of the prescribed
drugs is taken regularly, and without interruption. WHO approved standardized and effective cure for TB, called DOTS
(directly observed treatment short-course) is available in all countries of
the South-East Asia Region.
How is TB disease treated?
TB treatment involves taking multiple drugs. The most
common drugs used to fight TB are
isoniazid
rifampin
pyrazinamide
ethambutol
streptomycin
TB treatment requires taking several drugs together to
kill all the bacteria and preventing them from becoming resistant to one or
more drugs.
People with TB of the lungs or throat would initially need
to stay home from work or school so that they do not spread TB bacteria to
other people. After taking TB drugs two weeks, they will feel better and may
not be infectious to others. However, to be completely cured they would need
to take the drugs as prescribed for at least 6-8 months.
What are the side-effects of
TB drugs?
Very few people develop side-effects to TB drugs. Minor
side-effects include vomiting, nausea, loss of appetite, joint pain,
orange/red urine, or skin rash, which can be managed using simple medicines
or adjusting the dosages of the drugs.
Major side-effects include deafness and dizziness
(streptomycin); jaundice, vomiting (mainly rifampicin and isoniazid); visual
impairment (ethambutol), shock, purpura, or acute renal failure (rifampicin).
These side-effects need to be managed by a trained
physician and may require hospitalization.
Why do I need to take TB
medicines regularly?
TB bacteria die very slowly. It takes at least six months
to kill all the TB bacteria. People start feeling well after only a few weeks
of treatment. But TB bacteria are still alive in the body. You must continue
to take your medicine until all the TB bacteria are dead, even though you may
feel better and have no more symptoms of TB disease.
If you do not continue taking your medicine after you feel
better or are not regular, TB bacteria will grow again and you will become
sick again because the bacteria may become resistant to the drugs you are
taking. When this happens you may need different drugs to kill the TB
bacteria if the old drugs no longer work. These new drugs must be taken for a
longer time and usually have more serious side-effects.
If you become infectious again, you could spread TB
bacteria to your family, friends, or anyone else who spends time with you. It
is very important to take your medicine the way your doctor or nurse tells
you.
How can I prevent from
spreading TB?
The most important way to stop spreading TB is to take all
your medicines correctly. You need to do a sputum test at various time points
of your treatment. This test will show whether the treatment is effective.
You can further lessen the risk of spreading the infection
by:
covering your mouth when you cough.
avoiding close contact with other people.
staying in a room with good ventilation. TB
spreads in closed spaces where air doesn't move.
Remember, TB is spread through the air. People cannot get
infected with TB bacteria through handshakes, sitting on toilet seats, or
sharing plates and utensils with someone who has TB.
What if I have HIV
Infection?
Because HIV infection weakens the immune system, people
with TB infection and HIV infection are at very high risk of developing TB
disease. All HIV-infected people should be tested for TB. If they have TB disease, they must take TB medicines. <More
information on TB-HIV>
What is multidrug-resistant TB (MDR TB)?
When TB patients do not take their medicines as
prescribed, that is by missing doses, skipping some medicines or stopping
treatment ahead of time, the TB bacteria may become resistant to a certain
drug. This means that the drug can no longer kill the bacteria.
Drug resistance is more common in people who
have been in close contact with someone with
drug-resistant TB disease
do take their medicine irregularly
develop TB disease again, after having taken
TB medicine in the past
come from areas where drug-resistant TB is
common
Sometimes the bacteria become resistant to more
than one drug. Multidrug-resistant TB or MDR-TB means that a patient is
resistant to at least isoniazid and rifampicin, the two most important TB
drugs. This is a very serious problem. People with MDR TB disease must be
treated with different drugs. These drugs are not as effective as the
first-line drugs for TB are much more expensive and may cause serious side-effects. <More information on drug-resistant TB>-
What is the exact technical difference between
multi drug resistant TB and extensively drug resistant (XDR) TB?
Multi-drug resistant TB (MDR-TB) is an isolate of Mycobacterium
tuberculosis that is found to be resistant to at least rifampicin and isoniazid.
Extensively drug resistant TB (XDR-TB) is a sub-type of MDR TB. XDR TB is an
isolate of Mycobacterium tuberculosis that is found to be multi-drug
resistant (i.e. MDR-TB), which is also resistant to any fluoroquinolone and
at least 1 of the 3 injectable second-line drugs (capreomycin, kanamycin or
amikacin).
All drug-resistance in tuberculosis is man-made, caused by
inappropriate use of anti-TB drugs. That means providers who use non-standard
regimens, prescribe non-quality assured drugs, make patients pay for drugs
which they may not be able to afford, and provide treatment without ensuring
patient adherence through supportive supervision.
The laboratory tests required for the detection of drug resistance,
which are culture and drug susceptibility testing (DST), are technically
complicated, and therefore any laboratory undertaking drug sensitivity
testing (DST) should be accredited and part of a laboratory quality assurance
network for this activity through WHO or the national authorities.
Is
any treatment available for XDR-TB now or in the near future?
However, MDR-TB is difficult to treat and cure, requires a long
duration (>24 months) of treatment, is >200 times costlier than
treatment of drug susceptible TB, and is less likely to be successful. XDR-TB
is even more difficult to treat successfully, as there are very few drugs
left to which the organism is still sensitive. Due to this, XDR-TB is often
referred to as “virtually untreatable form of TB”.
Prevention of MDR-TB and XDR-TB is the key here. Most tuberculosis is
susceptible to first line medications and readily treatable, with
demonstrated treatment success rates of >85% for patients treated under
the DOTS strategy in countries in the Region. MDR-TB can be prevented by
proper application of the DOTS strategy and by adherence of health care
providers to the International Standards of TB Care. XDR-TB can be prevented by rational use of
second line anti-TB drugs consistent with the international guidelines for
management of MDR-TB, published by WHO.
Has
there been a recent WHO survey and/or report XDR-TB in India?
The National TB Programme of India
has undertaken state-wide representative surveys for drug resistance in
Gujarat and Maharashtra. These have been
completed and analyses are on-going. The testing for these surveys have been
done at accredited national institutes, including the Tuberculosis Research
Centre (TRC) in Chennai, an ICMR institution which has been designated as a
WHO supra-national reference laboratory. These results will show what the
true picture of MDR TB and XDR TB is in the general population in these
states, which will be much more accurate than reports from any referral
hospital, which has very limited implication for the country.
Data from Gujarat has been reported to
WHO and will appear in the 4th Global Drug Resistance Surveillance Report.
All isolates from patients which were found to be multi-drug resistant, have
been sent to the TB Research Centre in Chennai for testing for sensitivity to
second line drugs. Testing is ongoing. This will provide more representative
data regarding second-line drug resistance.
Is this rise in XDR-TB in any way linked to
co-infection with HIV and cross-reactions of anti-HIV and anti-TB drugs?
Evidence from drug resistance surveys India,
Nepal and Thailand
suggest that MDR TB is not rising. Future surveys may show if there is any
change over time. There is no evidence of any links with HIV infection or
anti-retroviral drugs.
Even
if not, how will this impact the HIV epidemic in the Region?
TB is a problem for persons living with HIV/AIDS, as it is among the
most common causes of illness and death among them. Normally persons living
with HIV/AIDS can be cured with DOTS treatment, particularly if they have
been provided with proper care and treatment for HIV. It is in the interest of countries,
especially those more severely affected by HIV, to support the TB programme’s
efforts to ensure that drug resistant TB does not increase in the future.
Do
countries have the capacity to diagnose XDR cases in time?
The TB Research Centre (TRC) in Chennai,
India, and the national
reference laboratory in Bangkok Thailand
are part of the WHO Supra-National Reference Laboratory Network, and have the
capability to perform DST for second-line drugs. There are other laboratories
that are undertaking such tests. However no others are recognized by WHO for
such tests in the Region. WHO is currently working with the Indian TB
Programme and TRC to develop and implement plans for enhancing the capacity
of laboratories in India
for second line anti-TB drug susceptibility testing. National TB control programme will need
increased funding and human resources to rapidly scale-up laboratories and
address drug resistant TB.
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