Acquired Immune Deficiency Syndrome (AIDS)

I can remember distinctly when all this started to rise to public consciousness.  It must have been around 1981.  I was in graduate school and I used to get a weekly publication with the charming title of "Morbidity and Mortality Weekly Report."   I remember reading the report of a "cluster" of cases of Kaposi's Sarcoma in San Francisco among homosexual men.  Kaposi's Sarcoma was a heretofore rare form of skin cancer, but now it had struck a whole group of persons living in the same city and with the same sexual orientation at the same time.

Clusters are always a red flag for the epidemiologists and the health care community.  And these men were seriously ill too.  It certainly looked communicable and a form of cancer.  And THAT was in itself very alarming.  It only occurred in immunosuppressed persons.  Moritz Kaposi, a Hungarian dermitologist from Vienna described it in 1872.  It was a malignant skin disease, but not really a sarcoma (a tumor of muscle tissue)  but serious enough.  Subsequently it has been found to have been caused (directly at least) by human herpesvirus 8.  Originally it was a disease found in elderly men of Mediterranean or Eastern European extraction, or in young African children under the age of 10.  

And it wasn't just Kaposi's sarcoma.  Other public health officials in other cities began noticing that in particular homosexual men were coming into clinics with all sorts of infections of a type that doctors only saw in cases of severe immunosupression..  It gradually dawned on people that this was all over the map.  In San Francisco, in Los Angeles, New York, Miami, Chicago, Montreal, London, Paris, Rome.  And in the beginning it seemed mostly a gay problem, but then other persons were seen with the immune deficiency:  hemophiliacs, for instance.  These were mostly children who received regularly a lot of blood products since their own bodies did not produce all the components for clotting their own blood.  This lack of clotting factors meant that a bruise or a cut could lead to death.  Now they were dying of something else entirely.   And then there were the needle-sharing intravenous drug users, junkies, persons found in all urban areas who used various injectable drugs.  Never the most sanitary of persons and with sterile needles in short supply, they shared.

There were of course many people who couldn't have cared less about what gay men did or viewed it as divine retribution for a sinful way of life,  Nor was there much concern for junkies who already seemed to be speeding on their way to the grave on greased skids anyway.   The victims were mostly denizens of a hidden urban world.  Didn't they already know that the wages of sin is death?   But then other people, like myself don't believe that what happens to people is necessarily any sort of judgment, or any such divinely ordained plan, and the rest of this article is discussing the facts without any sort of judgment at all on anyone or their tendencies. 

Gradually, however, it became evident that anyone could have AIDS, be they men, women, or children.  Many of them were drug users, and many of them were sex workers.   These were the denizens  of a hidden urban world of human beings most people would prefer not to see or think about.   But it was not exclusively a gay disease, a disease of males, or a disease of adults.  Even newborns could get the disease from their infected mothers, and when they did they seldom lived for more than a few years.

The most sensible advice to those at risk was to use a condom, and if you must share needles, clean them out with bleach (which killed just about anything) before re-using them.  As for hemophiliacs and other people unlucky enough to have received HIV contaminated blood in transfusions,  some way had to be found to make the blood supply safe, and to find a cure for those who had the infection already.

.  I knew people who knew people who had received tainted blood after some elective surgery and were thereby under a slow sentence of death. This was because blood banks in cities often bought the blood of people of dubious health in exchange for quick cash.  Maybe the blood would be tested for the presence of hepatitis B or C, which was horrible enough, but here was a problem even worse.

As investigators started to trace the history of the disease back through the maze of sexual partners in the gay community and among intravenous drug users it gradually became clear that the persons with symptoms were in the late stages of a disease that had been progressing for years and that for every person with full blown
AIDS there were many who were walking around and unaware that they were also infected, and that what they were infected with would inevitably kill them in a few years.  The immune system which is supposed to protect the individual was itself the target of the virus and proved in almost all cases, unable to resist the inexorable progression to total immunodeficiency.  The course of the untreated disease is about 10 years, with symptoms only appearing in the final  3 years.  In other words the people with full blown AIDS were only the tip of the iceberg.

Montagnier

 Meanwhile scientists in France and America were in pursuit of an answer to what was causing the disease. It was suspected that the virus was some kind of retrovirus and efforts were focused on recovering and culturing the virus (almost never an easy task) and then reproducing the disease as might be possible in non human primates.  Although at first there was a dispute as to who first isolated what became known as the Human Immunodeficiency virus (the French called it LAV, the Americans HTLV-III) it is now believed that Luc Montagnier's group in the Pasteur Institute was the first to isolate the virus.  Robert Gallo's group at the National Institutes of Health in the US claimed also to have isolated the virus.  The fact that Gallo's isolate matched the genetic make-up of the Montagnier isolate made it clear that some kind of inadvertent sharing of the Montagnier virus had occurred but this was not resolved until years later and after an official inquiry.

Gallo

Subsequently a means of detecting antibodies to HIV was found and when the beginning of widespread blood testing  occurred, it showed the truemagnitude of the problem.

What was discovered was that the virus is a retrovirus, an RNA strand which copies itself and inserts itself into the genome of the infected cells followed by replication of copies of the RNA virus and the production of particles which bud off and go on to infect other cells.  The cells that the virus infected happened to be an important part of the immune system itself, a subset of T cells which bear the CD4

receptor.  And not only CD4 positive T cells but the CD4 positive cells present in the intestinal mucosa, where CD4 positive T cells also express CCR5, which along with the CD4 receptor serves as the access point for the invasion by the HIV virus of the cell.  Then an immune response occurs which greatly reduces the infection and the initial flu like symptoms die down.  Unfortunately while the infection is checked for a time, it is not eliminated, and the virus slowly but steadily reduces the CD4/CCR5 cells until at some point a fatal immunodeficiency finally occurs.   During the period of latency the infected person feels well, something  which can last for years, when the HIV positive person is seemingly healthy and unwittingly  passes the infection along to anyone and everyone he or she may have sex with.  It is axiomatic in microbiology that the successful disease agent doesn't kill its host too quickly, but gives it time to pass the disease on to other hosts. 

So where did the HIV virus come from, and how did this happen?  Apparently from Africa where it had been present in the primate population there for thousands of years.  There are actually two different forms of HIV, HIV-1 and HIV-2.  While HIV-1 is thought to have originated in Cameroon among Chimpanzees in central Africa, HIV-2 originated in the sooty mangabey in coastal West Africa.  Both forms of HIV were derived from SIV (Simian immunodeficiency Virus) which is endemic in non human primates in Africa. It is now thought that SIV commonly was transferred to humans engaged in the hunting and preparation of "bush meat" from chimpanzees and other non human primates and that mutation in human hosts led to the evolution of HIV.

This rapid mutation rate, typical of RNA viruses, allows the tracing of various strains of virus to their likely origins. In a November 2007 article appearing in the   Proceedings of the National Academy of Science, a detailed genetic analysis of various forms of the HIV-1 virus suggested that it first came to the US in 1966.  The earliest documented case of AIDS in the US was that of a teenager from St. Louis, Missouri, named Robert Rayford.  He is thought to have been a male prostitute and since he died in 1969 at the age of 16, it is thought he must have contracted the disease as early as 1966.   Years after he died, his tissue samples were shown to contain antibodies to HIV antigens using the Western blot method.

In this age when roads have been built and people can traverse whole hemispheres in a matter of hours, the potential for spread of certain very nasty diseases is far greater than it used to be, when humans were more isolated and lived out their whole lives not far from where they were born.

Combining "high risk" sexual behavior with travel to far away places is a potent formula for disaster.  In much the same way as the sailors who sailed with Columbus brought syphilis back to Europe after 1492, HIV went from being a local virus to one that suddenly found itself in Haiti and then in the major cities of the US.  There it did not create a stir for almost ten years, when finally those who had been infected with the disease began to die in numbers that caused public health officials to notice.

 It is thought in fact that HIV may have been present in Africa as early as 1910.  The PNAS article cited above postulated in a very convincing way through detailed genetic analysis of different strains of HIV that the spread of AIDS was a consequence of of sex tourism to Haiti brought HIV to the US, after having been brought to Haiti from Africa in the early 1960s.  The virus was also found in Trinidad and Tobago and was spreading through the US in the gay community in the early 1970s.  In his book And the Band Played On, the AIDS activist Randy Shilts suggested that a gay Canadian air steward named Gaëtan Dugas was the source of the AIDS epidemic in America, having brought the disease from Africa and spread it to the gay communities of a number of American cities.  He was able to do this because of his prodigious sexual appetite and his mobility as an airline employee.  This is plausible enough, but it fails to explain the entirety of the phenomena of the early spread of the AIDS pandemic. 

Patient Zero and his sexual contacts

  This tracking of the HIV virus is possible because of its relatively high mutation rate and the sequencing and comparison of different HIV genomes.


By delving into the freezers of pathology labs in Africa, the US and Europe, preserved samples of tissue from

unexplained deaths from long ago have yielded evidence that the AIDS virus was around as early as the 1950s with the unexplained death of David Carr from Manchester, UK who died in 1959 and another 1959 sample of blood taken in Kinshasa in the Republic of the Congo in 1959 as well.  In 1973 2/3 of Ugandan children whose blood was sampled for a Burkitt's Lymphoma study, were retrospectively found to have antibodies to HIV. 

Whatever can be said for the devastation of the AIDS epidemic in the US and Europe, the picture in Africa is far worse.  With only about 15% of the population of the world, the continent of Africa contains about 70% of all living AIDS patients and accounts for about 70% of all AIDS deaths as of 2011.

Over 15% of the population in South Africa and Botswana is infected with HIV, which means more than 3 out of every 20 persons.  The countries of Southeast Africa from Rhodesia to Kenya have a prevalence of 5-15%.  And Subtype C of HIV-1, rare in the developed world is predominant in Africa and has a more rapid progression to death than other subtypes, where the progression takes about 10 years. 


It is fortunate that treatments for HIV infection have been found, a combination of antiviral drugs.  Unfortunately they are expensive, very dependent on compliance, and may cause serious side effects.  Also, while the life of the infected person may be extended many years, up to 40 perhaps, as yet there isn't a cure, a way of eliminating infection completely from the body.

And the timing of the treatment course is important as well, since those who present with AIDS cannot be easily restored to health and have a life expectancy at that point in months rather than years.