- Africa:
Malaria has been a serious problem in SubSaharan Africa for many
years. Malaria causes an estimated 2.7 million deaths per year,
with most of these deaths occurring in Africa. Ninety percent
of the world's malaria cases occur in Africa. Now, malaria outbreaks
are being reported in some locations of Africa that had been previously
thought to be at elevations too high for malaria transmission.
Some scientists hypothesize this is due to climatic change, while
others hypothesize that this is due to human migration. Also,
malaria has resurged in certain locations of Africa that had previously
had effective control programs, such as Madagascar, South Africa,
and Zanzibar.
- 1980s:
Malaria case numbers increased markedly during the 1980s in the
Indian Subcontinent and Southeast Asia.
- 1990s:
Malaria case numbers increased markedly during the 1990s in South
America, the Indian Subcontinent, and Southeast Asia. These increases
are largely linked to cessation of malaria vector control programmes.
- Drug
Resistance: Drug resistance is a growing problem, Chloroquine
is an extremely safe, cheap, and formerly very effective drug,
but in Southeast Asia, portions of South America, and a large
and increasing area of Africa chloroquine resistance levels are
high. In some areas of Southeast Asia there is resistance to all
the major drugs. Drug resistance is often connected with a legacy
of foolishly overusing or underdosing antimalarial drugs. Some
countries even laced salt with chloroquine.
- Vector
Resistance to Insecticides: Malaria mosquitoes are developing
resistance to the major classes of insecticides which have been
used to control the disease. Portions of the effort to eradicate
malaria during the 1950s and 1960s were scientifically naive and
politically uncommitted. Funding for vector control was cut prematurely
in areas, leading to resurgence in malaria cases and spread of
insecticide-resistant vector populations. The insecticide resistance
picture varies with vector species and region.
- Demographic
Change: Population and demographic changes have resulted
in more people moving into malaria-endemic areas, thereby increasing
transmission. Migration and the creation of new habitats have
resulted in people who have no natural immunity to the disease
being exposed. This results in epidemic malaria that is characterized
by much higher rates of disease and death.
- Environmental
Change and Human Mobility: Human environmental changes
such as road building, mining, deforestation, logging, and new
agricultural and irrigation projects have created new breeding
sites. Malaria transmission in newly logged or exploited areas
explodes just as a crop of outsiders with no immunity to the disease
come into work camps. This is particularly a problem in the Amazon
in Brazil. Indigenous people also suffer unprecedented onslaughts
of malaria. Incidence of malaria among Yanomami Indians in the
Amazon have leapt almost seventy-fold since contact with settlers
and gold miners, who are often plying their trades illegally.
Now, a quarter of Yanomami die of malaria, and others of tuberculosis,
whereas malaria was practically unknown among the Yanomami previously.
- Deterioration
and Abandonment of Control Efforts: In many regions,
including the Indian subcontinents, Madagascar, and portions of
South America and Southeast Asia, malaria control programs have
deteriorated or been abandoned because of political lack of commitment,
and lack of willingness to see things through to completion.
- Political
Indifference and Budget Cuts: Malaria research and control
budgets in many countries suffered huge cuts during the 1980s
and 1990s, yet malaria was spreading, sometimes to people such
as the Yanomami, who had had no previous exposure to it. Public
health is often the last consideration when politicians allocate
funding. The creation of wars and refugees provides conditions
ideal to the aggressive spread of malaria among displaced persons.
- What
About the Developed World? Malaria is primarily a disease
characteristic of the developing world. However, portions of the
southern United States and Western Europe, i.e. Italy are formerly
malaria-endemic regions. The former vectors are still present
in these areas. Although people's lifestyles in developed countries
have changed greatly since the early 1900s, with the widespread
use of screening and the advent of air conditioning, television
and other reasons to stay indoors during the summer, it is a "gamble"
as to when and where limited local malaria transmission could
resume. Competent vectors are present, while parasitemic persons
[returned travellers and persons coming from malaria endemic areas]
are sometimes present in these areas.
- What
About the Future? Although hypotheses vary about the
effect of increased urbanization, population movements, and possible
climatic change on malaria, one thing is certain: without the
political will to control malaria on both the part of developing
nations and in terms of scientific, technical and financial assistance
from the resource-wealthy developed world, malaria will continue
to be a very serious health problem.
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