Investment in national
tuberculosis (TB) programmes improves TB detection rates, a study published in
a special supplement of the Journal of
Infectious Diseases shows.
that each additional $1 per capita increase in the funding of national TB
programmes boosted TB detection rates in the following year by 2%. Reaching the
target detection rate of 70% was associated with major reductions in TB
incidence, prevalence and mortality.
The study involved the
22 countries with the highest TB burden and examined data from between 2002 and
“Increase in funding
for national TB programmes since 2002 and improved case detection and treatment
success rates were significantly associated with a downward trend in
tuberculosis incidence,” write the authors. “Achieving [the] high case
detection rate (i.e. above 70%) was associated with significantly (p <
0.01) lower tuberculosis incidence,
prevalence and mortality the following year, even when controlling for general
economic development and HIV prevalence as risk factors.”
There were an
estimated 9.4 million new cases of TB in 2009 and 1.7 million TB-related
for the control of TB include a 70% detection rate of sputum smear-positive
disease and the cure of 85% of these cases.
Global investment in
TB treatment and control programmes in 2011 is expected to reach $5 billion.
Some $3 billion of this funding is expected to be targeted at the 22 countries
with the highest burden of the disease.
An international team
of investigators wanted to see if this investment in the national TB programmes
of countries with the highest TB burden was associated with detection and cure
rates, and if changes in these performance indicators had an impact on TB incidence,
prevalence and mortality.
Total expenditure on
national TB programmes in these 22 countries between 2002 and 2009 amounted to
Pooling data from the
countries showed that, in 2009, TB incidence, prevalence and mortality rates were
302, 431 and 37 cases per 100,000 population respectively.
However, there was
wide variation between individual countries. For instance TB incidence in
Brazil was 96 cases per 100,000 compared to a rate of 971 per 100,000 in South
Africa. Brazil had the lowest TB mortality rate of just 2 per 100,000 population,
compared to a rate of 76 cases per 100,000 population in Tanzania.
Between 2002 and 2009
there were overall declines in TB incidence, prevalence and mortality (2.86,
9.84 and 1.90 cases per 100,000 population respectively).
found that higher expenditure on national TB programmes was associated with
higher TB detection rates.
Each $1 per capita
increase in national TB programme expenditure was accompanied by a 2% (p <
0.05) increase in TB case detection the following year.
When Russia and South
Africa were excluded from the analysis, each $1 per capita increase achieved a
38% higher detection rate.
However, there was no
association between higher expenditure on national TB programmes and treatment
Achieving the target
70% detection rate was associated with declines in TB incidence of 36 cases per
100,000 population, a fall in TB prevalence of 116 cases per 100,000
population, and a reduction of TB mortality of 7 cases per 100,000 population
(p < 0.01).
to the 17 countries with data on HIV showed even larger reductions in TB
incidence, prevalence and mortality (88, 183 and 12 cases per 100,000
“Our results suggest
that increased investment in national TB programmes, accompanied by increased
detection rates, will help further reduce the global burden of tuberculosis,”
conclude the authors. “An increased and sustained funder, donor, and
governmental commitment to ensuring high-quality national TB programmes is required.”