Monday, January 14, 2008

The Turbo Effect

Last month, December 07 to be precise, I wrote that in order to mark World Aids Day 2007, I would resurrect a number of articles I had written in the dim and distant past, on the subject of HIV/AIDS and plonk them on this site. It seems to date I have only posted one. Keeping my promise and because i think this piece remains relevant today, I have another offering, The Turbo Effect. Here it is essentially unedited from its original, published in US Medicine in 2002. It may, one day, be of interest to some wandering soul.

Cognitive Dissonance
In 1957 a Stanford University social psychologist Leon Festinger published his theory on behaviour called cognitive dissonance. In simple terms it is the distressing mental state in which [in Festinger’s words] people "find themselves doing things that don’t fit with what they know, or having opinions that do not fit with other opinions they hold”.
Festinger considered the human need to avoid dissonance as basic as the need for safety or to satisfy hunger. It is a drive to be consistent, so strong it can make us change our belief in an effort to avoid a distressing feeling. The more important the issue and the greater the discrepancy between behavior and belief, the higher the magnitude of dissonance that we will feel. In extreme cases cognitive dissonance is like our cringing response to fingernails being scraped on a blackboard—we’ll do anything to get away from the awful sound. After a year of near total immersion in HIV/AIDS in sub-Saharan Africa, I am struggling with an acute bout of “the CDs”.

Hard Talk
The source of my discomfit is a series of review articles in the International Journal of STD and AIDS 2003: 14. The authors are a group of international scientists whose principal author has a rather catchy name, David Gisselquist PhD. The articles address the factors that account for the rapid spread of HIV/AIDS in Africa. I admit that when I first read them, although my interest was piqued I was most influenced by the opinions of ‘my elders and betters’ in the world of HIV/AIDS and public health who abound in Nairobi. They almost unanimously dismissed the articles and the studies that underpin them as “flawed science”. About ten days ago I sat down to watch a current affairs program on BBC World satellite TV called “Hard Talk”, which specializes in the contentious and the topical; grilling those brave enough to subject themselves to inquisition. On this occasion, to my surprise and delight it was the aforementioned Gisselquist and some luminary from the London School of Tropical Medicine and UNAIDS. The ensuing battle was short sharp and painful, for my money Gisselquist came out on top and I once again set about the rather turgid prose and dense tables that epidemiologists deem as the only fitting means to publicize their science. The “CDs” set in after the first iteration.

Sex Central
The authors’ thesis is that almost from the outset of the pandemic, the consensus amongst influential AIDS experts has been that heterosexual transmission accounts for the overwhelming majority of adult HIV infections in Africa, yet the scientific evidence to support such a belief is questionable. They argue that the conventional wisdom regarding adult HIV infections in Africa emerged as a consensus in 1988. In that year,
the World Health Organization’s (WHO) Global Program on AIDS circulated estimates that 80% of HIV infections in Africa was due to heterosexual transmission, 10.8% from mother-to-child transmission, 6% from blood transfusions, 1.6% from contaminated medical injections and other health care procedures, and 1.6% from men who have sex with men (MSM) and injection drug use (IDU). Estimates for heterosexual transmission have inched upwards since. According to the World Health Organization’s 2002 World Health Report, ‘current estimates suggest more than 99% of HIV infections prevalent in Africa in 2001 are attributable to unsafe sex’.

They further argue that if experts had treated the consensus as an hypothesis—which it was and still is—and had used it to guide research to test competing hypotheses, it could have played a constructive role. Unfortunately, many experts have accepted the consensus as fact and not seen the need for further research to test its estimates. The result has been that the consensus has suppressed inquiry and dissent as researchers in Africa—and in Asia and the Caribbean—have often assumed sexual transmission without testing partners, without asking about health care exposures, and when conflicting evidence nevertheless emerges—such as infected adults who deny sexual exposures to HIV—routinely rejecting it.

Turbo Charge
The key to the Gisselquist et al argument is that studies in Africa show that sexual activity levels in the general population are comparable to those reported elsewhere, especially North America and Europe. Moreover, transmission efficiency studies amongst African couples produce estimates remarkably similar to studies of couples in the developed world. So, their argument goes, if African sexual behaviour is comparable to North American and the virus moves between heterosexual couples with the same efficiency north or south of the equator, why has the disease moved so much faster in Africa than in the developed world and why has heterosexual sex been more effective as a means of transmission in Africa than the developed world? What additional factors cause the so-called “turbo effect” that has enabled the disease to spread so rapidly compared with other regions of the world?

Quality of Care
The authors examine the history of AIDS in Africa from 1983 to 1988. Through extensive literature searches and studies they demonstrate that during the period there was considerable debate about the role of healthcare in the spread of the disease. They produce both anecdotal and science-based evidence to demonstrate that during this time, poor healthcare practices had a considerable impact on the spread of HIV/AIDS. Contaminated blood products and the use of unsterile needles for the administration of drugs and vaccines were acknowledged as key factors in the spread of the disease in certain regions of the Continent. This was recognized by experts but considered of secondary import to sexual activity.

They go on to argue there is evidence to show that in those early years of the spread of the disease, health care exposures caused more HIV than sexual transmission in some regions of Africa; suggesting that as much as half of all adult infections during that time were related to healthcare exposures.

Interests, Assumptions and Opportunism
Why was this evidence ignored? The authors argue that papers published around 1988 reveal a number of considerations that might have encouraged a mindset prepared to see heterosexual transmission as the driving force in Africa’s HIV epidemic. First, it was in the interests of AIDS researchers in developed countries—where HIV seemed confined to MSMs, IDUs, and their partners— social groups outside of general society - to present AIDS in Africa as a heterosexual epidemic devastating “ordinary people”. In a prominent 1988 article in Science, Piot and colleagues argued that ‘Studies in Africa have demonstrated that HIV-1 is primarily a heterosexually transmitted disease and that the main risk factor for acquisition is the degree of sexual activity with multiple partners, not sexual orientation’ .
Second, there may have been an inclination to emphasize sexual transmission as an argument for condom promotion, coinciding with pre-existing reproductive health programmes and efforts to curb Africa’s rapid population growth. Third, the role of sexual promiscuity in the spread of AIDS in Africa appears to have evolved in part out of prior assumptions about the sexuality of Africans. Fourth, health professionals in WHO and elsewhere worried that public discussion of HIV risks during health care might lead people to avoid immunizations. A 1990 letter to the Lancet, for example, speculated that ‘a health message—e.g., to avoid contaminated injection materials—will be misunderstood and that immunization programmes will be adversely affected’ .
In summary, peripheral and opportunistic considerations combined with an increasing display of cognitive dissonance amongst the cognoscenti to cause the evidence to be misinterpreted or completely ignored.

Yesterday’s News
Some might argue, “so what?” Even if its all true, these were events of nearly 20 years ago. Even if the quality of healthcare was a significant factor in the spread of HIV/AIDS in the 1980’s it no longer holds true. Across Africa basic healthcare has considerably improved and healthcare providers are well aware of and take precautions against the spread of HIV through faulty practices. Moreover, few would doubt that today heterosexual sex is by far the most likely means of transmission.

Trust Me I’m a Doctor
There are a number of reasons to be concerned about these studies. First, they raise genuine questions about the fidelity of scientific thought 20 years ago and do little to persuade the reader that things have changed for the better. Why should Africans trust those [predominantly from the rich developed world] who promised so much and yet have had little impact on the disease? Second, the image of African sexuality and promiscuity as the almost exclusive cause of the disease and the major focus for intervention tends to a patronizing even racist attitude towards the problem. Third, there is a growing body of opinion that circumstances and vested interest are driving those who manage HIV/AIDS in Africa to deal with it in a vertical or stove-piped manner, independent of other health issues; to view it as one scientist described as “HIV exceptionalism” . If we fail to realize that HIV/AIDS is yet another [albeit terrible] infectious disease to add to the many that plague Africa, there is a danger that we will fail to strengthen our public health and health services. The result will be a resurgence of poor healthcare services and practices as a significant factor in the continuing spread of the disease, a complete loss of trust in healthcare systems and an increase in disease of all kinds in Africa.

The Gisselquist writings bother me. I commend them to anyone interested in HIV/AIDS in the developing world. Flawed science or not, they raise questions about the blind faith we seem to place in science and our ability to accept conventional wisdom without demure. The problem is we have in turn asked millions of helpless people to trust us and if we lose that trust the battle against HIV/AIDS will receive a serious setback. The least we can do is re-examine the evidence and re-open the debate. Africans deserve the truth. As to whether I believe in the “turbo effect”, yes. Though I very much doubt that I will ever be able to identify it. I have one consolation; writing this has eased my cognitive dissonance.

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