The Challenge
Tuberculosis (TB) is an airborne, bacterial,
infectious disease mainly affecting the lungs. Those with the bacteria in their
lungs can infect others when they cough, which makes the disease highly
contagious. On average, someone is newly infected with TB
bacilli (the bacteria
that causes tuberculosis) every second.
With
more than 95% of TB cases occurring in low- and middle-income countries, those
least equipped to fight the disease are the most affected. Poor health systems
hinder efforts to stop the spread of TB and to treat those already
infected. And because HIV/AIDS weakens the immune system, those who are
HIV-positive are 26-31 times more likely to develop the disease than someone
without HIV. TB is a leading cause of death for AIDS patients, as TB bacteria
can take advantage of an individual’s immune system compromised by HIV. Of the
9.6 million individuals newly infected with TB in 2014, 12% were also
HIV-positive.
TB
causes 1.5 million deaths each year (400,000 of whom who are also HIV-positive)
and is a leading cause of death in low- and middle-income countries. The toll
comprised 890,000 men, 480,000 women and 140,000 children. Over 95% of TB
deaths occur in low- and middle-income countries, and it is among the top 5
causes of death for women aged 15 to 44.
Only
one preventive vaccine exists, and it is only partially-effective for children.
The vaccine, Bacilli Calmette-Guerin (BCG) is used to vaccinate children
against childhood tuberculosis meningitis in countries where TB is endemic. The
vaccine is less effective for adults, who usually contract pulmonary TB,
against which this vaccine has little effect. A successful adult TB vaccine has
not yet been developed.
The
evolution of the disease, along with misuse of the drugs used to treat it, has
led to the development of drug-resistant forms of TB. Multidrug-resistant TB
(MDR-TB) is difficult and expensive to treat, often failing to respond to
standard first-line drugs. MDR-TB infected about 480,000 people and killed
190,000 people in 2014. More recently, an even more deadly strain of the
disease has emerged, called Extensively Drug Resistant Tuberculosis (XDR-TB),
which responds to even fewer available medicines, including the most effective
second-line anti-TB drugs.
The Opportunity
TB
is treatable and curable. In many endemic countries, $20 will buy a full
six-month drug course of TB treatments; when administered properly (including
with information, supervision and support to the patient by a health worker or
trained volunteer), success rates are high. Between 2000 and 2014, an estimated
43 million lives were saved through TB diagnosis and treatment, with treatment
success improving each year.
The
global response to TB has made significant inroads against the disease. Since
1990, TB mortality has fallen by 47%, and as of 2015,the MDG target to halt and
reverse TB incidence has been achieved on a worldwide basis, in each of the six
WHO regions and in 16 of the 22 high-burden countries that collectively account
for 80% of TB cases. .
The
Global Fund to Fight AIDS, Tuberculosis and Malaria has supported the detection
and treatment of 13.2 million cases of TB, providing 80% or more of the world’s
external funding for TB. Despite this progress, much more remains to be
done. While funding for TB control has increased, funding for TB in 2014
amounted to only $1.5 billion, a 9% decrease from the previous year.
From
2016, the goal is to end the global TB epidemic by implementing the End TB
Strategy. Ratified by the World Health Assembly in May 2014 and (with targets)
linked to the newly adopted Sustainable Development Goals (SDGs), the strategy
serves provides a platform and a framework for countries to reduce the number
of TB deaths by 90% by 2030 (compared with 2015 levels), cut new cases by 80%
and ensure that no family is burdened with catastrophic costs due to TB.
