The AIDS virus

Posted on December 21, 2010

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When I was a little girl with pigtails, believe it or not, I wanted to grow up to be a biochemist. I loved chemistry at school and I wanted a long career mixing; testing chemicals and creating new compounds. My teacher was a big influence, he was a bit of a maverick and had all the hallmarks of a “mad scientist”.

He almost blew up the chemistry lab one afternoon by using too much hydrogen near an open flame; but even with the fire drills and the chaos, he made learning exciting and great fun. My passion however, was short-lived. It was quashed when I had to move to a different class taken by a straight-laced teacher, who bored everyone to tears. She had the personality of a dialling-tone….so for arguments sake, let’s call her Dr D.  

Before Dr D came along, my dream was to discover a cure for serious diseases affecting mankind. Sounds most altruistic, I know. My brother would joke, that knowing my luck, I would spend a lifetime living in a lab, only to stumble across a cure that someone else had discovered years earlier.

In 1983 the human immunodeficiency virus (HIV), the virus that causes the acquired immune deficiency syndrome (AIDS), was making headlines all over the world. The disease was recorded throughout the United States, Western Europe, and Africa. I vividly remember the press going big on raising awareness through much of the late 1980s. The idea of an epidemic that no-one knew much about, was something that terrified me.

Not long after the discovery of HIV, virologists identified a similar immune deficiency disease in captive laboratory Asian monkeys (macaques). The  simian immunodeficiency virus (SIV) is found naturally in a West African monkey species, the sootymangabey (Cercocebus atys), but it’s harmless to the host (SIVsm).

sootymangabeys, courtesy of WAPCA

The other closest relative of the primary human immunodeficiency virus (HIV-1) is another simian immunodeficiency virus carried by two species of chimpanzee (SIVcpz) – the west-central African chimpanzee (Pan troglodytes troglodytes) and also east-central African chimpanzee (Pan troglodytes schweinfurthii).

west-central African chimpanzee, courtesy of nature.com

I was recently debating the origins of AIDS with a professor at University College London (UCL). He told me of a very interesting paper published in the journal, American Scientist, by Professor Jim Moore (2004). There are many urban myths about how AIDS found its way into the human race; but did you know in scientific circles, there are actually four rivalling theories how the virus spread?

Moore states that molecular biologists continue to be baffled how these two distinct simian viruses, which have apparently coexisted alongside people for millennia, were able to suddenly pass into mankind multiple times within a few decades.  This explanation still eludes scientists today.  So what are the theories?

The first is that an oral polio vaccination (OPV) allegedly grown using the kidneys of “infected” monkeys and chimpanzees (neither species show any signs of symptoms) was said to have been given to more than 90 thousand people in Democratic Republic of the Congo, Burundi and Rwanda, during 1957 and 1960. The majority of scientific evidence published to date, suggests this theory is false.

The second and most popular theory is that SIV was transmitted to hunters from blood-to-blood contact with an infected primate. Hunters can suffer cuts and wounds from a primate fighting for its life and also if contaminated meat is consumed. Many Africans began moving to colonial capitals and ports in the 19th century; and it’s alleged that through “modernisation” those infected went on to spread the disease through sexual transmission.

courtesy of conservationist/photographer Karl Ammann,

The third theory is contaminated needles. In the 1950s there was a worldwide introduction of disposable plastic syringes. Doctors working in the developing world were able to administer medicines, including vitamins, analgesics and other common drugs through injections. At the time, plastic syringes were not cheap; so the same ones are thought to have been used over and over again…….and here’s the awful reality. Plastic syringes can’t be sterilised by boiling – they melt! So if the theory that a ‘cut hunter’ can carry a large number of viral particles in his bloodstream is true; and he went on to have an injection against another disease like sleeping sickness; and that same needle was used again on someone else; the virus could easily spread. The SIV virus also has a potential time-frame to mutate and adapt to become  HIV.

The last theory is a variation to the ‘cut hunter’ theory, that the origin of AIDS, might have had something to do with the pandemonium that followed colonial withdrawal from central Africa. In the 1900’s, the Congo territory became a Belgian colony under King Leopold II. During that time the natives suffered terrible atrocities and mass killings.

Ling Leopold II, Belgian

Those left alive were forced into labour camps where there was poor sanitation and malnutrition. Large scale vaccinations took place with shared needles against disease such as smallpox and sex workers were brought in to satisfy the labourers.  Some believe this theory pivots around an explanation about the genesis and initial spread of HIV during this period.

Of course there are still many unanswered questions that are far too complex for me to go into. Professor Moore concludes the origin of HIV was not fundamentally natural and that the emergence of HIV involved social change in one form or another.

AIDS is the final stage of HIV, which causes severe damage to the immune system and prevents the body from fighting infection and diseases like cancer.  Here are some very sobering facts from the World Health Organization (WHO).

  • In 2009 there were approximately 33.3 million people around the world living with HIV/AIDS, including 2.5 million children under the age of 15.
  • 7000 people are infected every day with HIV.
  • HIV has been found in saliva, tears, nervous system tissue and spinal fluid, blood, semen (including pre-seminal fluid, which is the liquid that comes out before ejaculation), vaginal fluid, and breast milk. However, only blood, semen, vaginal secretions, and breast milk generally transmit infection to others.
  • It can be spread through sexual transmission; blood (needle sharing and transfusions); mother to child; artificial insemination and infected organ donors.
  • It cannot be contracted from mosquitoes; hugging and touching objects that an infected person has touched.

There is no cure for AIDS at this time. There are antiretroviral drugs to help keep symptoms at bay and improve the quality of life of people who have already developed symptoms.

I am no longer pursing my scientific dream of finding cures; but I am hopeful that one day, a dedicated team of researchers will fulfill it for me.

The red ribbon is an international symbol of AIDS awareness

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