The Truth About HIV/AIDS

Back in 2000 or so, spurred on by the incomprehensibly denialist position taken by our then President, Thabo Mbeki, I started a HIV/AIDS information web page on our UCT Web server.  That is now sadly defunct (although still available via the Wayback Machine); however, given that Mbeki has very recently seen fit to reiterate some of his crazy notions, I am reinstating that page here.  Very little has changed in our basic knowledge since then: HIV still causes AIDS, we still have no vaccines against it, and it’s still a global problem.


The Durban Declaration

THE VAST MAJORITY OF PEOPLE WORKING IN THE BIOMEDICAL RESEARCH AREA SUPPORT THE CONTENTION THAT HIV IS THE ONLY CAUSE OF AIDS.

This is borne out by the fact that over 5000 people working with HIV/AIDS signed the “Durban Declaration”, which has its own Web site here.  This contains the Declaration itself (also published in Nature, 406: 15-16, 2000), as well as the list of signatories.  There are also a great number of references, many of which are accessible via the Web.

Here is an excerpt from the site:

Last year alone, 2.6 million people died of AIDS, the highest rate since the start of the epidemic.  If current trends continue, Southern and South-East Asia, South America and regions of the former Soviet Union will also bear a heavy burden in the next two decades.

Like many other diseases, such as tuberculosis and malaria that cause illness and death in underprivileged and impoverished communities, AIDS spreads by infection.  HIV-1, the retrovirus that is responsible for the AIDS pandemic, is  closely related to a simian immunodeficiency virus (SIV) which infects chimpanzees.  HIV-2, which is prevalent in West Africa and has spread to Europe and India, is almost indistinguishable from an SIV that infects sooty mangabey monkeys.  Although HIV-1 and HIV-2 first arose as infections transmitted from animals to humans, or zoonoses (2), both are now spread among humans through sexual contact, from mother to infant and via contaminated blood.

An animal source for a new infection is not unique to HIV.  The plague came from rodents.  Influenza and the new Nipah virus in South-East Asia reached humans via pigs.  Variant Creutzfeldt-Jakob disease in the United Kingdom came from ‘mad cows’.  Once HIV became established in humans, it soon followed human habits and movements.  Like other viruses, HIV recognizes no social, political or geographic boundaries.”


The Virology of AIDS

HIV particle. Russell Kightley Media

HIV particle. Russell Kightley Media

Picture courtesy of Russell Kightley
(click here to link to his site)

Human Immunodeficiency Virus (HIV) is a typical retrovirus of the genus Lentivirus, family Retroviridae: these are viruses which have single-stranded RNA as their genetic material, but multiply via a double-stranded DNA intermediate. 

The virus infects its target cells – which happen to mainly be helper T-lymphocytes – by specifically attaching to a protein carried on the surface of the cells known as CD4.  This is shown hereAn animated view of the whole infection process is shownhere; a more detailed schematic animated view here.  The process is discussed in detail here; however, what happens is that virus particles fuse with the target cells, and deliver their genetic material plus inside.  This RNA is then converted into DNA by means of a unique viral enzyme called reverse transcriptase.  The double-stranded DNA is then inserted randomly into a host cell  chromosome by means of another viral enzyme (integrase).  As part of the host chromosome it is expressed exactly the same way as host DNA – AND IS NOW PART OF THE CELL AND CANNOT BE REMOVED.  This means that infected cells are infected for life, which is different to most other types of virus infections: cells harbouring viral DNA continue to make infectious virus particles until they die or are killed.

SEE HERE FOR GRAPHICAL REPRESENTATION OF THE CELLULAR INFECTION PROCESS (Courtesy Russell Kightley)


Definitions of AIDS

From the National Institute of Allergy and Infectious Diseases (NIAID) site

“An HIV-infected person is diagnosed with AIDS when his or her immune system is seriously compromised and manifestations of HIV infection are severe.

“The U.S. Centers for Disease Control and Prevention (CDC) currently defines AIDS in an adult or adolescent age 13 years or older as the presence of one of 26 conditions indicative of severe immunosuppression associated with HIV infection, such as Pneumocystis carinii pneumonia (PCP), a condition extraordinarily rare in people without HIV infection. Most other AIDS-defining conditions are also “opportunistic infections” which rarely cause harm in healthy individuals.

A diagnosis of AIDS also is given to HIV-infected individuals when their CD4+ T-cell count falls below 200 cells/cubic millimeter (mm3) of blood.

Healthy adults usually have CD4+ T-cell counts of 600-1,500/mm3 of blood. In HIV-infected children younger than 13 years, the CDC definition of AIDS is similar to that in adolescents and adults, except for the addition of certain infections commonly seen in pediatric patients with HIV. (CDC. MMWR 1992;41(RR-17):1; CDC. MMWR 1994;43(RR-12):1).

In many developing countries, where diagnostic facilities may be minimal, healthcare workers use a World Health Organization (WHO) AIDS case definition based on the presence of clinical signs associated with immune deficiency and the exclusion of other known causes of immunosuppression, such as cancer or malnutrition.

An expanded WHO AIDS case definition, with a broader spectrum of clinical manifestations of HIV infection, is employed in settings where HIV antibody tests are available (WHO. Wkly Epidemiol Rec. 1994;69:273).”


Evidence That HIV Causes AIDS

There is very little doubt among the vast majority of people working with HIV or with people with AIDS, that HIV causes AIDS (see above).  The media tended to present everything in terms of a two-sided debate, with equal credence being given to both “sides”.  This is very misleading for the population at large, as they are presented with two sets of information that receive equal billing – and they are not qualified to judge between the viewpoints.

Quite simply, there is a vast body of evidence supporting the proposition that HIV causes AIDS.

I have presented some of the most compelling below; there is an enormous body of other evidence available on the Web, let alone in medical libraries.  The same cannot be said for the alternative view(s).  Perhaps the “best” of the denialist sites is is probably the “Rethinking AIDS” site.   This has a wealth of (dis)information on the subject, including such gems as the following, from Kary Mullis:

“If there is evidence that HIV causes AIDS, there should be scientific documents which either singly or collectively demonstrate that fact, at least with a high probability. There is no such document.” (Sunday Times London, 28 nov. 1993).

That this statement is nonsense is amply demonstrated by the following:

From the Durban Declaration site:

“The evidence that AIDS is caused by HIV-1 or HIV-2 is clear-cut, exhaustive and unambiguous.  This evidence meets the highest standards of science.  The data fulfill exactly the same criteria as for other viral diseases, such as poliomyelitis, measles and smallpox:

  • Patients with acquired immune deficiency syndrome, regardless of where they live, are infected with HIV.
  • If not treated, most people with HIV infection show signs of AIDS within 5-10 years.  HIV infection is identified in blood by detecting antibodies, gene sequences or viral isolation.  These tests are as reliable as any used for detecting other virus infections.
  • Persons who received HIV-contaminated blood or blood products develop AIDS, whereas those who received untainted or screened blood do not.
  • Most children who develop AIDS are born to HIV-infected mothers.  The higher the viral load in the mother the greater the risk of the child becoming infected.
  • In the laboratory HIV infects the exact type of white blood cell (CD4 lymphocytes) that becomes depleted in persons with AIDS.
  • Drugs that block HIV replication in the test tube also reduce viral load and delay progression to AIDS.  Where available, treatment has reduced AIDS mortality by more than 80%.
  • Monkeys inoculated with cloned SIV DNA become infected and develop AIDS.

Further compelling data are available.  HIV causes AIDS.  It is unfortunate that a few vocal people continue to deny the evidence.  This position will cost countless lives.”

From the NIAID site (excerpted):

AIDS and HIV infection are invariably linked in time, place and population group.

Historically, the occurence of AIDS in human populations around the world has closely followed the appearance of HIV. In the United States, the first cases of AIDS were reported in 1981 among homosexual men in New York and California, and retrospective examination of frozen blood samples from a U.S. cohort of gay men showed the presence of HIV antibodies as early as 1978, but not before then. Subsequently, in every region, country and city where AIDS has appeared, evidence of HIV infection has preceded AIDS by just a few years (CDC. MMWR 1981;30:250; CDC. MMWR 1981;30:305; Jaffe et al. Ann Intern Med 1985;103:210; U.S. Census Bureau; UNAIDS).

Many studies agree that only a single factor, HIV, predicts whether a person will develop AIDS.

Other viral infections, bacterial infections, sexual behavior patterns and drug abuse patterns do not predict who develops AIDS. Individuals from diverse backgrounds, including heterosexual men and women, homosexual men and women, hemophiliacs, sexual partners of hemophiliacs and transfusion recipients, injection-drug users and infants have all developed AIDS, with the only common denominator being their infection with HIV (NIAID, 1995).

In cohort studies, severe immunosuppression and AIDS-defining illnesses occur almost exclusively in individuals who are HIV-infected.

For example, analysis of data from more than 8,000 participants in the Multicenter AIDS Cohort Study (MACS) and the Women’s Interagency HIV Study (WIHS) demonstrated that participants who were HIV-seropositive were 1,100 times more likely to develop an AIDS-associated illness than those who were HIV-seronegative. These overwhelming odds provide a clarity of association that is unusual in medical research (MACS and WIHS Principal Investigators, 2000).

In developing countries, patterns of both rare and endemic diseases have changed dramatically as HIV has spread, with a far greater toll now being exacted among the young and middle-aged, including well-educated members of the middle class.

In developing countries, the emergence of the HIV epidemic has dramatically changed patterns of disease in affected communities. As in developed countries, previously rare, “opportunistic” diseases such as PCP and certain forms of meningitis have become more commonplace. In addition, as HIV seroprevalence rates have risen, there have been significant increases in the burden of endemic conditions such as tuberculosis (TB), particularly among young people. For example, as HIV seroprevalence increased sharply in Blantyre, Malawi from 1986 to 1995, tuberculosis admissions at the city’s main hospital rose more than 400 percent, with the largest increase in cases among children and young adults. In the rural Hlabisa District of South Africa, admissions to tuberculosis wards increased 360 percent from 1992 to 1998, concomitant with a steep rise in HIV seroprevalence. High rates of mortality due to endemic conditions such as TB, diarrheal diseases and wasting syndromes, formerly confined to the elderly and malnourished, are now common among HIV-infected young and middle-aged people in many developing countries (UNAIDS, 2000; Harries et al. Int J Tuberc Lung Dis 1997;1:346;Floyd et al. JAMA 1999;282:1087).

HIV can be detected in virtually everyone with AIDS.

Recently developed sensitive testing methods, including the polymerase chain reaction (PCR) and improved culture techniques, have enabled researchers to find HIV in patients with AIDS with few exceptions. HIV has been repeatedly isolated from the blood, semen and vaginal secretions of patients with AIDS, findings consistent with the epidemiologic data demonstrating AIDS transmission via sexual activity and contact with infected blood (Bartlett, 1999; Hammer et al. J Clin Microbiol 1993;31:2557; Jackson et al. J Clin Microbiol 1990;28:16).


Important HIV/AIDS Information Sites

An extremely authoritative source of information on HIV and vaccines

 One of the premier sites for information on HIV/AIDS is probably UNAIDS: this embodies a treasure trove of information, including:

There is also an HIV/AIDS information section, which has the best and newest statistics on the disease, with global and country reports.  They have an extremely valuable resource for educators in the Publications > Graphics section, where all sorts of PowerPoint and HTML documents are freely available.  One of the best documents on the site is “How does HIV effect me?“, dealing with issues such as transmission, etc.

 One of the best general information sites on HIV/AIDS is “The Body”, which has a stunning collection of information and links, updated to the minute.  The Body’s mission is to:

  1. Use the Web to lower barriers between patients and clinicians;
  2. Demystify HIV/AIDS and its treatment;
  3. Improve patients’ quality of life;
  4. Foster community through human connection.

The site also has a set of in-depth reports on the XIIth International AIDS Conference, from their own team of correspondents.

I have written another report, which can be found here.

The Avert site is also an excellent source of information on HIV/AIDS, and has a wealth of information on many aspects.  These include a huge deal of stuff on the community/health aspects, and on the scientific level:

Mission
The mission of the WHO-UNAIDS HIV Vaccine Initiative (HVI) is to promote the
development, facilitate evaluation, and address future availability of preventive HIV
vaccines, with a focus on the need of developing countries.

Ed Rybicki
This version 16/7/2003. Partially updated March 9th 2016

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