Infection with the human immune deficiency virus (HIV) the cause of the acquired immune deficiency syndrome (AIDS) has been reported worldwide. The overwhelming majority of people living with the disease live in low- and middle-income countries. Sub-Saharan Africa has the highest prevalence. Evidence for the contribution of social factors such as poverty, migration, and related consequences (poor education, family breakdown, substance abuse, etc.) are plausible explanations for the rapid spread of a disease that is transmitted sexually and through blood contact. However, the latter seem inadequate as explanations for the striking disproportionate burden of the epidemic in sub-Saharan Africa; an area accounting for about 10% of the world population yet where more than 60% of infected people live (Fig. 1).
Variation in HIV country prevalence has been attributed to various factors that increase the likelihood of infection. There is no direct association between the burden of disease and various measures of poverty (i.e., the poorest countries do not necessarily have the highest prevalence, e.g., Southern Africa leads the continent both in wealth and disease prevalence). The correlation between HIV and other sexually transmitted infections, especially those that cause ulceration, has been clearly demonstrated. It is interesting in the light of good evidence of the potential for medical circumcision to reduce new infections, that European countries with very low circumcision rates do not have a high HIV prevalence. There is also strikingly high disease prevalence in people of African ancestry residing in rich and not so poor countries compared with their country prevalence.
Human scalp hair varies from straight to spirally curly,1 yet biochemical analysis of hair of various curl phenotypes has reported similar results.2 Besides sharing darker hews of skin color most people of African ancestry fall within the very curly end of the spectrum of hair form.1 While conducting population studies of scalp disorders, which predominantly affect individuals of African descent,3,4 we found expected and unexpected results. First, most males (86%) wore close-shave haircuts; secondly, 1:10 of adult males had a scalp condition called folliculitis (acne) keloidalis nuchae (FKN); and finally and most unexpectedly that “haircut associated bleeding”– a previously unrecognized entity was common.
FKN is characterized by pustules and pimples, which often heal with keloid formation usually on the posterior scalp (but may be extensive). Our population prevalence increased with age (5.4% in boys in the last year of high school2 and 10.5% in men3). Further, 86% of males wore close shave hairstyles. The study included questions on haircut symptoms such as itch, transient pimples, and scabs (present in 47%; 216 of 459) – and it was while administering this part of the questionnaire that a number of participants volunteered a history of having had episodes of small amounts of bleeding during or soon after haircuts; an observation that was subsequently confirmed in 32% (51 of 157) of the remaining study participants.3 It is not unexpected that raised pimples in patients with FKN could be accidentally injured during very close shave haircuts. However, the prevalence of both haircut symptoms and bleeding was much higher than that of FKN in this study population. This may suggest that hair texture determines the force required to cut hair; where curliness because of higher required force positively correlates with an increased risk of accidental scalp injury during close shave haircuts.
No other general population studies investigating FKN in Africa were identified. However, studies conducted on African barbers have been published; one from Ethiopia but most of the data comes from Nigeria. One study reported on 131 barbers, only two of whom had formal sterilization available – the rest used antiseptics such as dettol and methylated spirits; accidental cuts occurred in 16 clients (11.7%).5 The latest study reported 90 barbering sessions conducted by 45 barbers. Clippers/blades were sterilized in 10%, disinfected in 72.5%, and in 17.5% nothing was done; accidental cuts occurred in 3.3% of the haircut sessions.6
Clearly, contributions to the risk of acquiring HIV infection are multifactorial. An explanation for the enigma of the disproportionate disease in sub-Saharan Africa was suggested by Bongaarts et al.7:
“Three or four factors are present in the largest epidemics. The presence of one or two alone is not sufficient to cause substantial epidemics. For example, male circumcision is rare in much of Western Europe, marriage is late, and most men and women have multiple partners during their sexually active years. Yet HIV prevalence is very low among heterosexuals in Western Europe. The likely explanation is the protective effect of condom use, the near absence of other STIs, and the lower prevalence of concurrent partnerships. In contrast, Southern Africa’s epidemics are very large because multiple and concurrent partnerships are relatively common, male circumcision and condom use are relatively rare, and other STIs are more prevalent.”
In addition to the usual investigated risk factors of HIV infection, Sawers et al. recently suggested that tropical infections could also increase susceptibility in low- and middle-income countries.8 They used cross-national data and multivariate linear regression analysis to investigate social and economic variables and incorporated data on parasitic and infectious diseases endemic in poor populations. The results demonstrate that these diseases significantly “… correlated with, and are potent predictors of, HIV prevalence.”8
In spite of what is known about HIV the efforts to prevent new infections have not been as effective as desired. Circumcision and the potential use of microbicides are recent additions to the prevention strategy of condoms and public education. However, while the discovery of an effective vaccine and cure remain elusive, potential clues should be vigorously pursued to identify all factors that can reduce disease transmission. The combination of a high prevalence of HIV, frequent close shave haircuts, significant FKN prevalence, and minimal or no routine clipper sterilization by most barbers; creates a potential environment for disease transmission.
At the L’Oreal 2010 meeting in Ghana, a Nigerian colleague in his presentation lamented the low number of males (65%) in his community who possessed and used their own clippers for their haircuts, something not widely practiced in other countries. He went on to say that in parts of Nigeria clippers are sold on street corners and that many people did not share them (later adding, privately, that “it was like sharing a tooth brush”). In spite of the high prevalence of HIV in Africa, Nigeria, the most populous country in the continent has a low prevalence. Could the popularity of private clipper ownership and the fact that most “barber studies” came from this country suggest awareness and be a factor that contributes to the lower HIV prevalence? Finally, the entity of “haircut associated bleeding” whether macro- or microscopic and its potential contribution to the burden of disease in sub-Saharan Africa at the very least requires further study – even if it is to disprove it!