Malaria
occurs in many locations of the tropical world and in some locations
of the subtropics. It is most common between the latitudes of 23.5o
North [Tropic of Cancer] and 23.5o South but cases (often
seasonal) also occur outside of these latitudes in areas such as portions
of South Africa [Kruger National Park and surrounding area - 25o
South] and New Delhi, India [28.5o North].
- Africa:
Malaria is very common in SubSaharan Africa. The predominant
species is Plasmodium falciparum. Plasmodium falciparum
is the most dangerous of the four species of human malaria.
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. Chloroquine resistance
is widespread 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,
such as the highlands of Kenya. 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.
- Asia:
Malaria is widespread in numerous countries in Asia and Oceania,
including India, Pakistan, Bangladesh, Thailand, Vietnam,
Laos, Myanmar, Cambodia, Indonesia, Papua New Guinea. Malaria
also occurs in portions of Iran and the Middle East. Plasmodium
falciparum is common, as is Plasmodium vivax. Plasmodium
falciparum infections unfortunately increased during the
1990s in India and Sri Lanka. Resistance in Plasmodium
falciparum to multiple drugs is present in portions of
Cambodia, Myanmar, Thailand, and Laos, and chloroquine resistance
is widespread in Asia. Plasmodium malariae also occurs
in this area.
- South
America: Malaria occurs at altitudes below 1000 m
in portions of countries in South America, including Brazil,
Peru, Colombia, Bolivia, Ecuador, Venezuela, Guyana, Suriname,
French Guiana. The most common species in this area is Plasmodium
vivax, although there is an unfortunate increase in Plasmodium
falciparum cases, particularly in regions where control
programs have deteriorated or been abandoned since the early
1990s.
- Central
America and Southern Mexico: Malaria occurs in low-altitude
areas of the countries of Central America including Honduras,
Nicaragua, and Guatemala. Limited numbers of cases occur in
Panama, Costa Rica, and southern Mexico. Active control programs
are in place in several of these countries. Plasmodium
vivax is the dominant species, and fortunately, remains
susceptible to chloroquine.
- Caribbean:
Malaria remains eliminated from several countries of the Caribbean.
However, malaria [P. falciparum] occurs in Haiti and
in limited numbers of cases in the Dominican Republic.
- Europe:
Malaria [Plasmodium vivax] occurs in Turkey, Armenia,
and Azerbaijan.
- North
America: Malaria eradication programmes during the
1940s and 1950s, along with widespread use of screening, eliminated
malaria from this region, and there is no year-to-year local
transmission. However, isolated, rare cases of local transmission
have occurred. North America, the Caribbean region, Europe,
Australia, and Mexico and Central America are the major success
stories of malaria vector control efforts.
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