people living with HIV is increasing. This increase is due mainly to the life
prolonging effects of antiretroviral therapy and an increase in the number of new HIV
diagnoses in Western Europe since 2002, combined with a relatively stable number of
new HIV infections each year in North America. Overall, approximately 2.1 million
people in North America, Western and Central Europe were living with HIV in 2007.
In continent North America, the percentage of people living with HIV
is 3,5%.The United States of America is one of the countries with the largest number
of HIV infections in the world. Alaska has medium percentage of people living with
HIV. Canada has low percentage of people living with HIV as compare to the rest of
the continent with the annual number of newly reported HIV infections between 2495
and 2538 per year. The countries like Mexico, Honduras have comparatively high
percentage of people living with HIV.
In western and central Europe, the percentage of people living with
HIV is 1,9%. Heterosexually acquired HIV infections, most of which were among
immigrants and migrants, accounted for the largest proportion (42%) of new HIV
diagnoses in Western Europe. The HIV epidemics in Spain, Italy, France and the
United Kingdom, is largest in Western and Central Europe. The annual number of
newly diagnosed HIV infections has more than doubled in the United Kingdom, from
4152 in 2001 to 8925 in 2006. Germany, Portugal, Netherland have medium
percentage of people living with HIV. In Central Europe, the number of newly
diagnosed HIV infections in 2007 surpassed 100 in only three countries: Poland (750),
Turkey (290) and Romania (180). Elsewhere, the epidemics are comparatively small
and in countries like Hungary, Montenegro and Serbia more than1000 HIV infections
in total have been reported since the epidemic began.
In central Asia and eastern Europe, the percentage of people living
with HIV is 4,3%.An estimated 150 000 people were newly infected with HIV in
2007 bringing the number of people living with HIV in Eastern Europe and Central
Asia to 1.6 million. In this region, HIV prevalence is highest in these two countries
: the Russian Federation and Ukraine. The annual numbers of newly reported HIV
diagnoses are also rising in Azerbaijan, Georgia, Kazakhstan, Kyrgyzstan, the
Republic of Moldova, Tajikistan and Uzbekistan (which now has the largest epidemic
in Central Asia).
In south/south-east Asia the percentage of people living with HIV is
19,7%.In Asia, national HIV prevalence is highest in South-East Asia, with wide
variation in epidemic trends between different countries. While the epidemics in
Cambodia, Myanmar and Thailand all show declines in HIV prevalence, those in
Indonesia (especially in the Papua province) and Viet Nam are growing. Although the
proportion of people living with HIV in India is lower than previously estimated, its
epidemic continues to affect large numbers of people. Overall in Asia, an estimated
4.9 million people were living with HIV in 2007, including the 440 000 people who
became newly infected in the past Year. In china HIV prevalence varies and the
epidemic tends to be concentrated in certain regions only. Prevalence trends in India
vary greatly between states and region. In India national adult HIV prevalence is of
0.36%. In Pakistan, HIV prevalence is increasing. The estimated number of people
living with HIV in Vietnam has more than doubled between 2000 and 2005 from
120 000 to 260 000.The HIV epidemic in Indonesia is among the fastest growing in
Asia. In Cambodia HIV prevalence has fallen to an estimated 0.9%. In Thailand and
Myanmar there is decline in HIV prevalence.
In middle east and north Africa, the percentage of people living with
HIV is 1,2%. Despite recent improvements in some countries, epidemiological
surveillance in this region remains limited. Nevertheless, using available HIV
information it is estimated that 35 000 people acquired HIV in 2007, bringing to
3800 00 the total number of people living with HIV in the region. Sudan is the country
with the highest prevalence in the region,
Sub-Saharan Africa remains the most affected region in the global
AIDS epidemic. In Sub-Saharan Africa, the percentage of people living with HIV
is62,5%. More than two thirds (68%) of all people HIV-positive live in this region
where more than three quarters (76%) of all AIDS deaths in 2007 occurred. It is
estimated that 1.7 million people were newly infected with HIV in 2007, bringing to
22.5 million the total number of people living with the virus. Unlike other regions, the
majority of people living with HIV in sub-Saharan Africa (61%) are women .The
scale and trends of the epidemics in the region vary considerably, with southern Africa
most seriously affected. This sub region accounts for 35% of all people living with
HIV and almost one third (32%) of all new HIV
infections and AIDS deaths globally in 2007. HIV prevalence is very high in these
eight countries: Botswana, Lesotho, Mozambique, Namibia, South Africa, Swaziland,
Zambia and Zimbabwe.
In most of the countries in East Africa adult HIV prevalence is either stable or has started to decline.
In West and Central Africa, HIV prevalence has remained stable
overall and Nigeria has the largest epidemic in this sub region.
HIV prevalence in the Caribbean is estimated at 1.0% in 2007.
Prevalence in this region is highest in the Dominican Republic and Haiti, which
together account for ,including the 17 000 who were newly infected in 2007.
In Oceanic , the percentage of people living with HIV is 0,2%. An
estimated 14 000 people acquired HIV in Oceania ( Australia, New Zealand and New
Guinea) in 2007, bringing to 75 000 the number of people living with the virus in this
region.
How HIV/AIDS has spread geographically over time (this is called the spatial diffusion) ?
Most virologists believe that HIV-1 began with the transfer of a similar virus from
chimpanzees to human in central Africa, possibly in Congo. Research shows that the
HIV virus spread from chimps to humans in south-eastern Cameroon.Virologists said
the resulting HIV epidemic among humans correlates to the growth of urban centres
near this area, principally the present-day city of Kinshasa in the Democratic Republic
of the Congo, which began as a colonial centre for Belgium. The oldest known HIV-1
group genetic sequence comes from a 1959 blood sample from a man, also from
Kinshasa. Central Africa as being the epicenter of the virus. By 1960 a large number
of people in this region were infected with HIV, which shows as genetic diversity of
the virus. From there, events seeded the epidemic in different parts of the world. It is
thought in 1970s HIV-1 was taken from central Africa to Haiti by vacationers
returning home. In late 1970s from Haiti, HIV-1 was taken to the United States by
American tourists, and from the United States it spread to Europe.
The probabilities of spreading AIDS:
During the late 19th and early 20th century, much of Africa was ruled by colonial
forces. In areas such as French Equatorial Africa and the Belgian Congo, colonial rule
was particularly harsh and many Africans were forced into labour camps where
sanitation was poor, food was scarce and physical demands were extreme. These
factors alone would have been sufficient to create poor health in anyone, so SIV could
easily have infiltrated the labour force and taken advantage of their weakened immune
systems to become HIV. A stray and perhaps sick chimpanzee with SIV would have
made a welcome extra source of food for the workers.
Many of the labourers would have been inoculated with unsterile needles against diseases such as smallpox (to keep them alive and working), and that
many of the camps actively employed prostitutes to keep the workers happy, creating
numerous possibilities for onward transmission. A large number of labourers would
have died before they even developed the first symptoms of AIDS, and those that did
get sick would not have stood out as any different in an already disease-ridden
population. And from there spreads to ruling countries and in their other colonial
countries
The other type of the virus is HIV-2. HIV-2 was not identified until
1986. The spread of HIV-2 was quite different from the spread of HIV-1. HIV-2
seems to have began in West Africa, probably in the small nation of Guinea-Bissau
and was identified in 1986.By the year 1989, Guinea-Bissau is a former Portuguese
colony, and the disease spread from there to Portugal (in Europe) and to two former
Portuguese colonies in Africa, Mozambique and Angola. From these four nations,
HIV-2 then spread elsewhere in Africa. By the year 1994,the disease spread to North
America , to South America from Guinea-Bissau and Angola, and to Europe from
Guinea-Bissau, Angola and Mozambique. From Guinea-Bissau , it spread to Asia by
the year 1994. From Europe also it spreads in Asia and especially from U.S.A .It
spreads in Thailand. By 1994, Portugal was the main centre of dispersion of HIV-2
through Europe. And in this way the disease spread to all other parts of the world by
infected tourist etc.
Until recently, the origins of the HIV-2 virus had remained relatively
unexplored. HIV-2 is thought to come from the SIV in Sooty Mangabeys rather than
chimpanzees, but the crossover to humans is believed to have happened in a similar
way (i.e. through the butchering and consumption of monkey meat). It is far rarer,
significantly less infectious and progresses more slowly to AIDS than HIV-1. As a
result, it infects far fewer people, and is mainly confined to a few countries in West
Africa. The virus had originated in Guinea-Bissau and that its spread was most likely
precipitated by the independence war that took place in the country between 1963 and
1974 (Guinea-Bissau is a former Portuguese colony). The first European cases of
HIV-2 were discovered among Portuguese veterans of the war, many of whom had
received blood transfusions or unsterile injections following injury, or had possibly
had relationships with local women.
The first documented case of AIDS was observed in 1976 and by
the end of the 20th century the disease had been reported in over 190 countries.
Globally, 40 million adults and children were living with HIV/AIDS at the end of
2001. Of infected adults, 48 percent were women. Of 5 million people newly infected
with HIV in 2001, 3.4 million of them were in sub-Saharan Africa, making this sub-
region the most susceptible to the virus. In the last several years, infection rates among
women have increased significantly, especially in sub-Saharan Africa.
Four of the earliest known instances of HIV infection are as follows:
∙A plasma sample taken in 1959 from an adult male living in what is now the Democratic Republic of the Congo.
∙A lymph node sample taken in 1960 from an adult female, also from the Democratic Republic of the Congo.
∙HIV found in tissue samples from an American teenager who died in St. Louis in 1969.
∙HIV found in tissue samples from a Norwegian sailor who died around 1976.
