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Where? Aids Spread
The question of exactly where the transfer took
place, and where the 'epidemic' officially first developed has
always been controversial. Some have suggested that it is dangerous
to even try to find out, as AIDS has frequently been blamed on an
innocent person or group of individuals in the past. However,
scientists remain keen to find the true origin of HIV, as most agree
it is important to understand the virus and its epidemiology in
order to fight it.
Given the evidence we have already looked at, it is
likely that Africa was indeed the continent where the transfer of
HIV to humans first occurred (monkeys from Asia and South America
have never been found to have SIVs that could cause HIV in humans).
However, who exactly spread the virus from Africa , to America and
beyond remains a mystery. It is quite possible that separate
'pockets' of the virus could have been developing in a number of
different countries years before the first cases were ever
officially identified, making it virtually impossible to trace one
single source.
There are a number of factors that may have
contributed to the sudden spread of HIV, most of which occurred in
the latter half of the twentieth century.
Both national and international travel undoubtedly
had a major role in the initial spread of HIV. In the US ,
international travel by young men making the most of the gay sexual
revolution of the late 70s and early 80s would certainly have played
a large part in taking the virus worldwide. In Africa , the virus
would probably have been spread along truck routes and between towns
and cities within the continent itself. However, it is quite
conceivable that some of the early outbreaks in African nations were
not started by Africans infected with the 'original' virus at all,
but by people visiting from overseas where the epidemic had been
growing too. The process of transmission in a global pandemic is
simply too complex to blame on any one group or individual.
Much was made in the early years of the epidemic of
a so-called 'Patient Zero' who was the basis of a complex
"transmission scenario" compiled by Dr. William Darrow and
colleagues at the Centre for Disease Control in the US. This
epidemiological study showed how 'Patient O' (mistakenly identified
in the press as 'Patient Zero') had given HIV to multiple partners,
who then in turn transmitted it to others and rapidly spread the
virus to locations all over the world. A journalist, Randy Shilts,
subsequently wrote an article based on Darrow's findings, which
named Patient Zero as a gay Canadian flight attendant called Gaetan
Dugas. For several years, Dugas was vilified as a 'mass spreader' of
HIV and the original source of the HIV epidemic among gay men.
However, four years after the publication of Shilts' article, Dr.
Darrow repudiated his study, admitting its methods were flawed and
that Shilts' had misrepresented its conclusions.
While Gaetan Dugas was a real person who did
eventually die of AIDS, the Patient Zero story was not much more
than myth and scaremongering. HIV in the US was to a large degree
initially spread by gay men, but this occurred on a huge scale over
many years, probably a long time before Dugas even began to travel.
As blood transfusions became a routine part of
medical practice, an industry to meet this increased demand for
blood began to develop rapidly. In some countries such as the USA ,
donors were paid to give blood, a policy that often attracted those
most desperate for cash; among them intravenous drug users. In the
early stages of the epidemic, doctors were unaware of how easily HIV
could be spread and blood donations remained unscreened. This blood
was then sent worldwide, and unfortunately most people who received
infected donations went on to become HIV positive themselves.
In the late 1960's haemophiliacs also began to
benefit from the blood clotting properties of a product called
Factor VIII. However, to produce this coagulant, blood from hundreds
of individual donors had to be pooled. This meant that a single
donation of HIV+ blood could contaminate a huge batch of Factor
VIII. This put thousands of haemophiliacs all over the world at risk
of HIV, and many subsequently contracted the virus.
The 1970s saw an increase in the availability of
heroin following the Vietnam War and other conflicts in the Middle
East , which helped stimulate a growth in intravenous drug use. This
increased availability and together with the development of
disposable plastic syringes and the establishment of 'shooting
galleries' where people could buy drugs and rent equipment, provided
another route through which the virus could be passed on. |
