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One of the Millennium Development Goals, agreed by
world leaders and the United Nations summit in 2000,
pledges to, "halt and reverse the incidence of
malaria and other major diseases" by 2015. Research
shows that at the end of 2004, 107 countries and
territories had areas at risk of malaria
transmission and some 3.2 billion people lived in
areas at risk of malaria transmission. An estimated
350–500 million clinical malaria episodes occur
annually; with more than 1 million deaths each year;
80% estimated to occur in sub-Saharan Africa, and
mostly among children under five years old.
According to the 20th Report of the WHO Expert
Committee on Malaria, malaria is also the world's
leading cause of childhood mortality, and kills a
child somewhere in the world every 30 seconds.
Malaria further has serious economic impacts in
Africa, slowing economic growth and development and
perpetuating the vicious cycle of poverty - WHO
reports that malaria costs the continent more than
US$12 billion each year in healthcare expenditures
and lost productivity, a sum that is roughly
equivalent to all the foreign aid that flows into
Africa each year.
The disease and transmission patterns of malaria
vary between regions and even within individual
countries, because of variations in the malaria
parasites, growing drug and insecticide resistance,
climate change, natural disasters, poverty,
deteriorating health systems, HIV/AIDS prevalence
and armed conflict.
A research study, by the UK-based European Centre
for Medium Range Weather Forecasts, published by
Nature, claims that malaria epidemics could be
predicted up to five months ahead by using a special
combination of climate models. The predictions could
be used to strategically target insecticides and
drugs to regions at risk of an outbreak. The study
was based on an early-warning system developed by
Botswana's National Malaria Control Programme. The
system uses information about rainfall, health
surveillance and the population's vulnerability to
malaria to detect unusual changes in seasonal
patterns of disease.
By using a combination of climate models, the team
eliminated uncertainties in the system's
predictions. To prove their new approach, they tried
retrospectively predicting malaria epidemics in
Botswana from 1982 to 2002. The team found that the
risk of an epidemic in Botswana rises just after a
season of heavy rainfall and that temperature and
rainfall drive the abundance of both mosquitoes and
parasites. The research further points out that the
method only applies to areas where malaria occurs in
climate-related epidemics and not in areas where the
disease is a year-round problem. Although epidemic
malaria accounts for only a small proportion of
cases worldwide, it can be important at a regional
level, contributing to a significant rise of cases
and deaths. Following Botswana's lead, other
countries in sub-Saharan Africa are now developing
early-warning systems.
South Africa has also introduced a new research
initiative that aims to find new and more effective
ways of fighting malaria. The South African Malaria
Initiative (SAMI) will promote collaborations
between scientists at South African universities,
science councils and other institutions, as well as
create links with researchers across Africa. It will
focus on developing new medicines and better ways to
diagnose malaria, as well as researching how the
malaria parasite interacts with its mosquito host.
Even though South Africa has relatively few malaria
cases compared to other countries in the region, the
disease still poses a serious threat, says Jane
Morris, director of the African Centre for Gene
Technologies, because the parasite is becoming
increasingly resistant to drugs and insecticides.
The WHO recently requested pharmaceutical companies
to end the marketing and sale of “single-drug”
artemisinin malaria medicines, in order to prevent
malaria parasites from developing resistance to this
drug. The use of single-drug artemisinin treatment –
or monotherapy – hastens development of resistance
by weakening but not killing the parasite. The
once-popular chloroquine has already lost its
effectiveness in almost every part of the world.
Between 1999 and 2004, 95% of African children
treated for malaria were given chloroquine, even
though the drug only cured half of malaria cases in
many countries.
Additionally, to anticipate and prevent the onset
and spread of drug resistance in the long term, WHO
urges the global malaria research community and the
pharmaceutical industry to rapidly invest in the
design of the next generation of antimalarial drugs.
The Executive Secretary of the Roll Back Malaria
Partnership highlights that expanded advocacy is
also essential to turn the tide on malaria;
increased advocacy will raise the global profile of
the disease, educate communities around the world
and also help to ensure that the world dedicates
more resources to defeating this epidemic. |
