[this is the first of three parts; click here to get the complete paper]
Insanity is doing the same thing, over and over again, but expecting different results.[1]
The common explanation for HIV epidemics in sub-Saharan Africa is that sex between men and women accounts for almost all infections in adults. Considering the long-term failure of programs focusing almost exclusively on sex to roll back high levels of HIV infection in Africa, it’s time to step back and take a fresh look at the situation.
Sterilization of reused instruments is unreliable in many health care settings in Africa. In national surveys of hospitals and other health care facilities in seven countries (Ghana, Kenya, Namibia, Rwanda, Tanzania, Uganda, and Zambia) during 2002-10, from 17% of facilities in Rwanda to 83% in Namibia did not have equipment to sterilize instruments (the median among seven countries was 33% without equipment).[2] Reuse of unsterilized skin-piercing instruments is common in cosmetic services as well. For example, in Kampala, Uganda, people get manicures on the street from itinerant providers who reuse instruments from one client to another.
Wherever skin-piercing instruments are reused without sterilization people can get HIV from traces of blood from a previous patient or client. HIV can live for hours in dry blood,[3] such as on a razor, and for weeks if kept wet, such as in a used syringe or needle. Boiling reliably kills HIV, but wiping and even soaking with bleach or spirits does not, except under controlled conditions.
Recognizing these risks, WHO warns UN employees that[4] “unsafe blood collection and transfusion practices and the use of contaminated syringes account for a notable share of new infections,” in unspecified world regions, but assures them: “Because we are UN employees, we and our families are able to receive medical services in safe healthcare settings, where only sterile syringes and medical equipment are used, eliminating any risk to you of HIV transmission as a result of health care.”
WHO further warns UN employees [5] “If you are not carrying your own syringes and needles, avoid having injections unless they are absolutely necessary,” and “Avoid tattooing and ear piercing. Avoid any procedures that pierce the skin, such as acupuncture and dental work, unless they are genuinely necessary. Before submitting to any treatment that may give an entry point to HIV, ask whether the instruments to be used have been properly sterilized.”
It’s clear from WHO advice to UN employees that skin-piercing procedures are not the minor risks for HIV that HIV prevention messages have misled Africans to believe. Based on available evidence, it’s possible – even likely – that more than half of African adults with HIV got it from blood contact or from a spouse or other sex partner who got it through blood contact.[6] Here’s some of the evidence (summarized here, expanded below):
1. No one has explained how heterosexual sex[7] could infect such high percentages of adults in Africa but not elsewhere.
2. Sexual transmission was not enough to create an HIV epidemic in Africa before 1900.
3. Across Africa, in countries where more people are aware of blood contacts as risks for HIV, the percent of adults infected with HIV is less.
4. Many studies in Africa that follow HIV negative adults to see who gets HIV find that those who report no sex partners or 100% condom use get HIV almost as fast as adults who report possible sexual exposure to HIV.
5. Many studies in Africa report HIV infections linked to medical injections, blood tests, circumcision, and other blood exposures.
6. In countries where governments investigate unexpected HIV infections, HIV concentrates in injection drug users and men who have sex with men.
7. In countries where governments react to stop unsafe practices in health care, HIV similarly concentrates in injection drug users and men who have sex with men.
Following sections elaborate this evidence. This note concludes with some suggestions about how Africans can “break the silence” to protect themselves and their families and to stop Africa’s HIV epidemics.
1. Low percentages of adults get HIV from heterosexual sex outside Africa
Outside Africa, only 0.3% of adults (3 in 1,000) are HIV-positive, and HIV infects twice as many men as women.[8] In much of the world, HIV infections concentrate in adults with specific high risk behaviors – men who have receptive anal sex with men (MSM), and people who reuse syringes and needles to inject illegal drugs (IDU). Notably, the biggest risk for HIV among prostitute women in much of the world is IDU, not sex.
In the US and Europe, many men who are MSM and IDUs have sex with women, and many women who are IDUs sell sex to pay for drugs. Although MSM and IDUs thereby infect some heterosexual partners, their partners on average die before passing it on. In other words, heterosexuals in the US and Europe are “dead ends,” not “drivers” of the epidemic.
In contrast, in 14 countries[9] in Africa, 5%-26% of adults aged 15-49 years are infected, more women than men. The common explanation for such high levels of HIV infection among “low risk adults” (ie, not MSM or IDU) in Africa is that somehow heterosexual transmission is faster and more efficient in Africa. But no one has explained how that could be so. Transmission between discordant couples is similar across countries. Sexual behavior in Africa is similar to behavior in the US and Europe. Male circumcision is more common in Africa than in Europe.
2. No heterosexual HIV epidemic in Africa before 1900
HIV in humans comes from simian immunodeficiency virus (SIV) in chimpanzees and gorillas. Scientists can “sequence” individual HIV and SIV, describing the order of their component parts. Because sequences change over time, viruses whose sequences are more similar are more closely related – ie, they have a more recent common ancestor that lived in a human, chimpanzee, or gorilla some time ago.
A comparison of HIV and SIV sequences reveals four groups of HIV, each of which resulted from a different event in which SIV from a chimpanzee or gorilla got into a human. We know this because the HIV sequences in each of these groups are more similar to some of the SIV from chimpanzees or gorillas than to HIV in the other three groups. Also, from studying the differences among HIV sequences within each group, scientists can estimate that HIV in the two oldest groups began to spread among humans around 1900.[10]
Thus, we can surmise that SIV passed from chimpanzees and gorillas to humans at least four times in the last 100 years or so.[11] The best explanation for how this happened is that hunters and butchers got SIV-contaminated blood into cuts, giving them HIV infections. If this happened four times in the recent past, it likely happened hundreds of times in the past 100,000 years. We know that chimpanzees have been infected with SIV for at least that long, because distantly related SIV can be found in two populations east and west of the Congo River which have bred separately for more than 100,000 years.
The fact that there is no continuing (surviving) chain of infection from any of the hundreds of HIV infections that cut hunters and butchers (presumably) got from chimpanzees in past centuries tells us that humans who got HIV before 1900 were more likely to die than to pass it on to other humans. In other words, before 1900, HIV transmitted too slowly through sex to spread any of these infections into an epidemic.
In The Origins of AIDS,[12] Jacques Pepin identifies the post-1900 introduction of injections into Central Africa as the change that allowed HIV to spread. Peter Piot, the long-time former head of UNAIDS concurs:[13]
…Pepin suggests that the efficiency of sexual transmission of HIV-1 was too low to enable the virus to spread beyond a few individuals. He then shows how mass campaigns organized by French and Belgian colonial administrations to treat tropical diseases such as yaws, sleeping sickness, leprosy, syphilis, and malaria exposed hundreds of thousands of people to intravenous or intramuscular injections with potentially contaminated needles and glass syringes… As far as the origins of AIDS are concerned, unless some completely new evidence emerges, it will be difficult to come up with a better explanation than Pepin’s.
If Pepin and Piot are correct, all HIV infections in the world come from unsafe health care in Africa, if not immediately and directly, then at earlier points in the chains of transmission from cut hunters and butchers to all current infections.
[1] Attributed to Albert Einstein, but disputed
[2] In countries with more than one survey, I report data from the latest survey. Source: ORC Macro. Service Provision Assessment Surveys as follows: Kenya 2004; Namibia 2009; Rwanda 2001; Rwanda 2007; Tanzania 2006; Uganda 2007; Zambia 2005. Calverton, Maryland: ORC Macro, various years. Available at: http://www.measuredhs.com/publications/publication-search.cfm?type=21 (accessed 21 September 2012).
[4] Quote from p. 9 in: UNAIDS, Living in a World with HIV and AIDS: Information for employees of the UN system and their families. Doc no: UNAIDS/04.27E, July 2004, revised December 2004. Geneva: UNAIDS, 2004. Available at: http://whqlibdoc.who.int/unaids/2004/9291733717_eng.pdf (accessed 12 January 2011).
[6] This condition is satisfied if 30% of adults get HIV from blood. If so, an adult has a 51% (=30% + 21%) chance to get HIV from blood (30%) or through sex with someone who got it from blood (21% =70% x 30%).
[7] As used in this note, “heterosexual sex” includes all insertive sex between men and women, including penile-vaginal and penile-anal sex.
[9] These 14 countries are: Botswana, Lesotho, Malawi, Mozambique, Namibia, South Africa, Swaziland, Zambia, and Zimbabwe in Southern Africa; Cameroon and Gabon in Central Africa; and Kenya, Tanzania, and Uganda in East Africa.
[11] Vallari A, Holzmayer V, Harris B, et al. Confirmation of putative HIV-1 group P in Cameroon. J Virol 2011; 85: 1403-07.
[12] Pepin J. The Origin of AIDS. London: Cambridge University Press, 2011.
[13] Piot P. Ingredients for a perfect storm. Science 2011; 334: 1642-1643.
Bloodborne HIV: Don't Get Stuck! 