The Role of Disease-Specific Infectivity and Number of Disease Exposures on Long-Term Effectiveness of the Latex Condom

The Importance of Context: Model Projections on How Microbicide Impact Could Be Affected by the Underlying Epidemiologic and Behavioral Situation in 2 African Settings

“…This is the result of the HIV incidence in Hillbrow being much greater than in Cotonou, resulting in a smaller relative reduction in incidence (for the same level of use) because individuals are more frequently exposed to infection. 46 These results agree with other modeling studies that have illustrated the overall impact of core group HIV prevention interventions would decrease as an epidemic progresses, 47,48 and the impact of other HIV prevention interventions would be less in settings with more generalized epidemics. 49 -51 The findings illustrate the potential importance of microbicides but highlight the potential problems in generalizing the results of microbicide trials to other epidemiologic settings.…”

“…In our analysis, the STI efficacy of the microbicide contributed more to impact in Cotonou, the lower STI prevalence setting, because the microbicide resulted in a 6-fold greater relative decrease in STI prevalence than in Hillbrow, where STIs were more prevalent and so harder to affect because individuals are more frequently exposed to infection. 46 The differences in the relative importance of a microbicide's STI efficacy highlight that different candidate microbicide products may have different levels of impact in different settings. Indeed, eventually, it is likely that the greatest efficacy may be achieved using combinations of active ingredients 3 that maximize both a product's HIV and STI efficacy.…”

A systematic review of published evidence on intervention impact on condom use in sub-Saharan Africa and Asia

“…41 When considering this evidence, it is important to keep in mind that condom effectiveness against an STI depends on the infectivity of that specific STI. 90 Other methods of validation included asking both male and female partners about their condom use, 37 80 or comparing the reported coital frequency and condom use data with the number of condoms distributed. 40 Although UNAIDS and other agencies have invested in methodological research to identify how best to enquire about condom use, 89 several imprecise measures were used in the studies reviewed.…”

Syphilis and the city

“…4-6 The The probability of infection depends on the number of episodes of intercourse with an infected partner, the infectivity of the sexually transmitted disease, and the estimated per-episode probability (f = 0.03) of condom failure. 2 The resulting probability of infection in a condom user is estimated as P ncondomuser = 1 ÿ (1 ÿ f *inf ) n , with number of infected partners estimated using prevalence data for white women from the Centers for Disease Control and Prevention (CDC). 2,3 The data from the CDC were broken down by demographic and regional categories, so we took the average of the statistics for age group 25-29 and for the New York geographic region to account for both as a rough estimate.…”

“…2 The resulting probability of infection in a condom user is estimated as P ncondomuser = 1 ÿ (1 ÿ f *inf ) n , with number of infected partners estimated using prevalence data for white women from the Centers for Disease Control and Prevention (CDC). 2,3 The data from the CDC were broken down by demographic and regional categories, so we took the average of the statistics for age group 25-29 and for the New York geographic region to account for both as a rough estimate. Risk from syphilis and chancroid were also calculated, but found to be negligible, with estimated prevalence of 0.45 and 0. possibility of contracting an STD increases with number of exposures even with correct condom use.…”