Minimal impact of circumcision on HIV acquisition in men who have sex with men

Abstract

Abstract. Background:Men who have sex with men (MSM) are disproportionately affected by HIV. The proven efficacy of circumcision in reducing the risk of HIV acquisition among African heterosexual males has raised the question of whether this protective effect may extend to MSM populations. We examined the potential impact of circumcision on an HIV epidemic within a population of MSM. Methods: A mathematical model was developed to simulate HIV transmission in an MSM population. The model incorporated both circumcision and seropositioning, and was used to predict the reduction in HIV prevalence and incidence as a result of the two interventions. Estimates for the time required to achieve these gains were also calculated. Results: We derive simple formulae for the decrease in HIV prevalence with increased circumcision. Our model predicts that if an initially uncircumcised MSM population in a developed country with a baseline HIV prevalence of 10% underwent universal circumcision, HIV incidence would only be reduced to 95% of preintervention levels and HIV prevalence to 9.6% after 20 years. In the longer term, our model predicts that prevalence would only decrease from 10% to 6%, but this would take several generations to achieve. The effectiveness of circumcision increases marginally with higher degrees of seropositioning. Conclusions: The results of these calculations suggest that circumcision as a public health intervention will not produce a substantial decrease in HIV prevalence or incidence among MSM in the near future, and only modest reductions are achievable in the long-term.

Mathematical models for the study of HIV spread and control amongst men who have sex with men

“…Monitor changes in sexual behaviour 1988-1994 [39,66,100] Reduce the prevalence of other STIs 1988-2008 [12,33] Use microbicides for HIV control in bathhouses 2006 [21] Serosorting accompanied with increased condom use 2009 [24] Circumcision in MSM is unlikely to be an effective control measure 2009-2010 [23,128] Reducing the basic reproduction number below one has often been used to determine if an intervention will eliminate HIV. Strategies similar to those shown above have been suggested but assuming a substantially higher efficacy, such as reducing the infectiousness of the late disease stage to zero [50], which seems optimistic.…”

“…Substantially reduce the number of dual-role MSM 1989 [61] Highly effective sex-education programmes 1999-2004 [75,76] Substantial migration from high to low sexual activity groups 2001 [25] Markedly decrease the level of unsafe sexual practices 2007-2008 [71,118] Combination of annual HIV screening test, counselling, and education 1991 [113] Combination of ART intervention and increased condom use 2009 [43] Moderately decrease the proportion of receptive sexual practices 2010 [128] Reduction in infectiousness Extremely widespread use of ART 1994ART -2004 and even accompanied with annual testing of all risk groups 2010 [64] HIV testing programmes even with perfect diagnosis rate 2008 [112] Promote condom use alone even with perfect compliance if R0 is very high (due to condom failure)…”

The changing molecular epidemiology of HIV in the Philippines

“…Increasing case numbers may also be related to a decreased protective effect of circumcision among MSM (Londish et al, 2010). Knowledge of current prevailing HIV genotypes may lead to a better understanding of the epidemiology of the local HIV epidemic.…”

Can Male Circumcision Have an Impact on the HIV Epidemic in Men Who Have Sex with Men?

“…Estimating this potential population-level impact thus requires mathematical modeling. Two such studies have considered this question, both for high-resource settings [21], [22]. Both found the overall long-term population-level impact of a hypothetical MSM-MC intervention to be modest (∼5% decrease in prevalence for explored scenarios), although the one paper conducting an explicit cost-benefit analysis found MSM-MC to be likely cost-effective and possibly cost-saving [21].…”