The term "smoking gun" is a reference to an object or fact that serves as conclusive evidence of a crime or similar act...[2]
A recent double-barreled smoking gun calls attention to long-term mistakes that have left Africans at risk to get HIV from health care. The first smoking barrel was the discovery of a large HIV outbreak in South Africa in 2013-14 that is best explained by bloodborne transmission, most likely during health care. The second smoking barrel is the subsequent silence by public health and HIV/AIDS officials and experts about the likelihood that unsafe health care caused the outbreak.
In 2010-14, researchers collected HIV from a random sample of adults in a large mostly rural study area in uMkhanyakude district in KwaZulu-Natal. The team then sequenced 1,376 HIV samples (i.e., determined the order of HIV’s component parts). Because HIV changes over time, similar sequences from two or more people suggest recent and close transmission links. Among the 1,376 sequences, the study team found a cluster of 63 very similar HIV. The study estimated that HIV from one person in June 2013 had somehow reached and infected 63 people within 18 months through November 2014.[3]
Because the 1,376 HIV sequences came from an estimated 9% of HIV-positive adults in the study area, the observed cluster of 63 similar HIV may well be 9% of a much larger cluster of 600-800 closely linked infections in the study area. Moreover, because many of the 63 similar HIV came from people living in a town on the border of the study area, the cluster likely extends outside the area. And transmission appeared to be ongoing when the study stopped collecting HIV samples in 2014.
In their conference presentation, the study team showed a “tree” diagram linking the 63 similar sequences to an estimated parent virus in mid-2013 (slide 10 in [3]). This tree, showing rapid and recent transmission links, is similar to a tree linking HIV sequences from the investigated outbreak from unsafe health care discovered in Roka, Cambodia in 2014 (Figure 2b in [4]).
The study that reported the 2013-14 outbreak in KwaZulu-Natal suggested HIV might have spread through sex, but provides no information about sexual risks for anyone in the cluster. In any case, the possibility that sex could transmit HIV from 1 to 63 infections (much less hundreds) in 18 months is vanishingly small, considering:
Sexual transmission is far too slow. Even between spouses, it takes on average years for one to infect the other. Combining data from five studies in Africa in which many or most spouses did not know one was infected, HIV-negative partners got new HIV infections at a rate of less than 10% per year (Table A2.1). In a 2016 national survey in South Africa, in couples with at least one partner HIV-positive, less than half of their partners were infected.[5]
According to self-reported sexual behavior, having multiple partners had little to do with HIV transmission in the study area. Repeat surveys in the study area during 2004-15 identified 2,367 new HIV infections in adults. Only 43 (1.8%) of 2,367 adults with new infections reported more than one sex partner in the previous year, while 189 (8.0%) of 2,367 adults with new infections said they were virgins (Table 1 in [6]).
Researchers from the African Health Research Institute and the University College London collected HIV from the study area in 2010-14 and then sequenced HIV samples and discovered the cluster of 63 infections in 2017. They reported their discovery in March 2018 at the Conference on Retroviruses and Opportunistic Infections in Boston.
Because it is almost impossible for such an outbreak to come from anything other than bloodborne transmission, the government of South Africa could protect public health by investigating to find and fix whatever caused it. Investigators should ask people in the cluster what skin-piercing procedures they received and where during 2013-14, and then invite others who visited suspected facilities to come for HIV tests.
Even if someone wants to argue or believe that sex could somehow account for all infections in the cluster, bloodborne transmission remains a possible explanation. That possibility challenges the government to investigate. We[1] have found no evidence the government of South Africa has taken any steps to investigate that possibility.
During their 2018 Conference presentation, the research team did not acknowledge the possibility unsafe health care caused the outbreak, and none of the discussants mentioned such risks. To the best of our knowledge, as we are writing this more than two years after the cluster was reported in 2018, no expert in gene sequencing and no HIV expert or official in any international or foreign organization has acknowledged the possibility the cluster comes from unsafe health care.
Considering the many experts who are aware of the cluster, continuing silence about what is so obvious – that the cluster likely (or at least possibly) comes from unsafe health care – shows that people who understand the implications of the cluster are choosing to keep silent. That in turn suggests they are aware of pressures not to say what is obvious. Their silence is strong circumstantial evidence – smoking gun evidence – that officials who control research funds and jobs for people working on HIV do not want them to say that bloodborne risks very likely or even possibly caused the outbreak.
Silence about the likelihood the large cluster of 63 closely linked infections in KwaZulu-Natal came from bloodborne risks is a recent example of more than three decades of inadequate responses to evidence of HIV from health care in Africa (Chapters 3 and 4).[7] Those who are silent include many experts in gene sequencing who have only recently started to look at HIV from Africa. Gene sequencing experts coming new to Africa’s HIV epidemics have not been implicated in decades of inadequate responses to unexplained HIV infections. But now they, too, are silent.
Those who are silent are not explaining why. Because people are at risk, speculating about why experts and officials are not doing their jobs is a distraction. Setting aside distractions, the tasks at hand are: to get investigations underway to find and fix skin-piercing procedures that infect people; and to warn people about risks to get HIV from health care as long as those risks are not found and fixed.
1. Simon Collery co-authored this chapter. See also: Gisselquist D, Collery S. Africa’s HIV epidemics: Evidence from a double-barreled smoking gun. Social Science Research Network [internet] 1 May 2020. Available at: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3590251 (accessed 1 May 2020).
2. Smoking gun. Wikipedia [internet] 29 April 2020. Available at: https://en.wikipedia.org/wiki/Smoking_gun (accessed 23 August 2020).
3. Coltart CEM, Shahmanesh M, Hue S, et al. Ongoing HIV micro-epidemics in rural South Africa: the need for flexible interventions. Conference on Retroviruses and Opportunistic Infections, Boston, 4-7 March 2018. Abstract 47LB and oral abstract.
4. Rouet F, Nouhin J, Zheng D-P, et al. Massive iatrogenic outbreak of human immunodeficiency virus type 1 in rural Cambodia, 2014-2015. Clin Infect Dis 2018; 66: 1733-1741.
5. ICF. South Africa Demographic and Health Survey 2016. Rockville (MD): ICF, 2019.
6. Akullian A Bershteyn A, Klein D, et al. Sexual partnership age pairings and risk of HIV acquisition in rural South Africa. AIDS 2017; 31: 1755-1764.
7. Fernando D. The AIDS pandemic: searching for a global response. J Assoc Nurses AIDS Care 2018; 29: 635-641.