PHA-Exchange> TUBERCULOSIS: More facts to spread

[Claudio]

From: "Vern Weitzel" <vern.weitzel at undp.org>

> > Tuberculosis (TB) is a contagious disease. Like the common cold, it
spreads through the air. Only people who are sick with TB in their  lungs
are infectious. When infectious people cough, sneeze, talk or spit, they
propel TB germs, known as bacilli, into the air. A person
> > needs only to inhale a small number of these to be infected.
> >
 Left untreated, each person with active TB disease will infect on average
between 10 and 15 people every year. But people infected with  TB bacilli
will not necessarily become sick with the disease. The  immune system "walls
off" the TB bacilli which, protected by a thick
> > waxy coat, can lie dormant for years. When someone's immune system is
weakened, the chances of becoming sick are greater.
> >
    * Someone in the world is newly infected with TB bacilli every  second.
     * Overall, one-third of the world's population is currently    infected
with the TB bacillus.
    * 5-10% of people who are infected with TB bacilli (but who are  not
infected with HIV) become sick or infectious at some time  during their
life.
> >
> > The largest number of cases occurs in the South-East Asia Region,  which
accounts for 33% of incident cases globally. However, the estimated
incidence per capita in sub-saharan Africa is nearly twice  that of the
South-East Asia, at 350 cases per 100 000 population. Actually,
the highest mortality per capita is in  the Africa Region.
> >
 Nowadays, strains  that are resistant to a single drug have been documented
in every  country surveyed. _ Drug-resistant TB  is caused by  inconsistent
or partial treatment, when patients do not take all their  medicines
regularly for the required period because they start to feel
> > better, because doctors and health workers prescribe the wrong
treatment regimens, or because the drug supply is unreliable. A
particularly dangerous form of drug-resistant TB is  multidrug-resistant TB
(MDR-TB), which is defined as the disease caused by TB bacilli resistant to
at least isoniazid and rifampicin.
Poorly supervised or incomplete  treatment of TB is worse than no treatment
at all.  While drug-resistant TB is generally  treatable, it requires
extensive chemotherapy (up to two years of   treatment) that is often
prohibitively expensive (often more than 100  times more expensive than
treatment of drug-susceptible TB), and is
> > also more toxic to patients.
> >