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OBJECTIVE: To describe a dynamic compartmental simulation model for Botswana and India, developed to identify the best strategies for preventing spread of HIV/AIDS. METHODS: The following interventions were considered: a behavioural intervention focused on female sex workers; a conventional programme for the treatment of sexually transmitted infections; a programme for the prevention of mother-to-child transmission; an antiretroviral treatment programme for the entire population, based on a single regimen; and an antiretroviral treatment programme for sex workers only, also based on a single regimen. FINDINGS: The interventions directed at sex workers as well as those dealing with sexually transmitted infections showed promise for long-term prevention of human immunodeficiency virus (HIV) infection, although their relative ranking was uncertain. In India, a sex worker intervention would drive the epidemic to extinction. In Botswana none of the interventions alone would achieve this, although the prevalence of HIV would be reduced by almost 50%. Mother-to-child transmission programmes could reduce HIV transmission to infants, but would have no impact on the epidemic itself. In the long run, interventions targeting sexual transmission would be even more effective in reducing the number of HIV-infected children than mother-to-child transmission programmes. Antiretroviral therapy would prevent transmission in the short term, but eventually its effects would wane because of the development of drug resistance. CONCLUSION: Depending on the country and how the antiretroviral therapy was targeted, 25-100% of HIV cases would be drug- resistant after 30 years of use.

Using a sexually transmitted diseases simulation model (STDSIM), we made projections of HIV spread for four profiles of sexual behaviour reflecting patterns encountered across the developing world: 1) much commercial sex, no short relationships; 2) commercial sex, concurrent short relationships; 3) concurrent relationships, no commercial sex; 4) serial short relationships, some commercial sex. We studied the effects of increasing condom use in three target groups: commercial sex workers (CSWs); men engaging in commercial contacts and short relationships; and females in steady relationships. The projections indicated that the CSW and male strategies were more effective in reducing HIV incidence than the strategy focusing on females in steady relationships. In the long run, even the group of men and women with one recent partner were better protected against HIV infection by condom use in high-risk contacts than by condom use in steady relationships. Furthermore, the numbers of HIV cases prevented per condom used were 7 to 500 times higher for condoms used by CSWs or men engaging in short relationships and commercial sex than for ones used by females in steady relationships. The results indicated the merit of focusing on high-risk groups irrespective of the pattern of sexual behaviour, even in epidemics that had already spread throughout populations.

Abstract Lives saved have become a standard metric to express health benefits across interventions and diseases. Recent estimates of malaria-attributable under-five deaths prevented using the Lives Saved tool (LiST), extrapolating effectiveness estimates from community-randomized trials of scale-up of insecticide-treated nets (ITNs) in the 1990s, confirm the substantial impact and good cost-effectiveness that ITNs have achieved in high-endemic sub-Saharan Africa. An even higher cost-effectiveness would likely have been found if the modelling had included the additional indirect mortality impact of ITNs on preventing deaths from other common child illnesses, to which malaria contributes as a risk factor. As conventional ITNs are being replaced by long-lasting insecticidal nets and scale-up is expanded to target universal coverage for full, all-age populations at risk, enhanced transmission reduction may--above certain thresholds--enhance the mortality impact beyond that observed in the trials of the 1990s. On the other hand, lives saved by ITNs might fall if improved malaria case management with artemisinin-based combination therapy averts the deaths that ITNs would otherwise prevent. Validation and updating of LiST's simple assumption of a universal, fixed coverage-to-mortality-reduction ratio will require enhanced national programme and impact monitoring and evaluation. Key indicators for time trend analysis include malaria-related mortality from population-based surveys and vital registration, vector control and treatment coverage from surveys, and parasitologically-confirmed malaria cases and deaths recorded in health facilities. Indispensable is triangulation with dynamic transmission models, fitted to long-term trend data on vector, parasite and human populations over successive phases of malaria control and elimination. Sound, locally optimized budget allocation including on monitoring and evaluation priorities will benefit much if policy makers and programme planners use planning tools such as LiST - even when predictions are less certain than often understood. The ultimate success of LiST for supporting malaria prevention may be to prove its linear predictions less and less relevant.

Abstract Background In Zanzibar, the Ministry of Health and partners accelerated malaria control from September 2003 onwards. The impact of the scale-up of insecticide-treated nets (ITN), indoor-residual spraying (IRS) and artemisinin-combination therapy (ACT) combined on malaria burden was assessed at six out of seven in-patient health facilities. Methods Numbers of outpatient and inpatient cases and deaths were compared between 2008 and the pre-intervention period 1999-2003. Reductions were estimated by segmented log-linear regression, adjusting the effect size for time trends during the pre-intervention period. Results In 2008, for all age groups combined, malaria deaths had fallen by an estimated 90% (95% confidence interval 55-98%)(p < 0.025), malaria in-patient cases by 78% (48-90%), and parasitologically-confirmed malaria out-patient cases by 99.5% (92-99.9%). Anaemia in-patient cases decreased by 87% (57-96%); anaemia deaths and out-patient cases declined without reaching statistical significance due to small numbers. Reductions were similar for children under-five and older ages. Among under-fives, the proportion of all-cause deaths due to malaria fell from 46% in 1999-2003 to 12% in 2008 (p < 0.01) and that for anaemia from 26% to 4% (p < 0.01). Cases and deaths due to other causes fluctuated or increased over 1999-2008, without consistent difference in the trend before and after 2003. Conclusions Scaling-up effective malaria interventions reduced malaria-related burden at health facilities by over 75% within 5 years. In high-malaria settings, intensified malaria control can substantially contribute to reaching the Millennium Development Goal 4 target of reducing under-five mortality by two-thirds between 1990 and 2015.

Abstract Background Since 2003, the Global Fund has supported the scale-up of HIV/AIDS, tuberculosis and malaria control in low- and middle-income countries. This paper presents and discusses a methodology for estimating the lives saved through selected service deliveries reported to the Global Fund. Methods Global Fund-supported programs reported, by end-2007, 1.4 million HIV-infected persons on antiretroviral treatment (ARV), 3.3 million new smear-positive tuberculosis cases detected in DOTS (directly observed TB treatment, short course) programs, and 46 million insecticide-treated mosquito nets (ITNs) delivered. We estimated the corresponding lives saved using adaptations of existing epidemiological estimation models. Results By end-2007, an estimated 681,000 lives (95% uncertainty range 619,000-774,000) were saved and 1,097,000 (993,000-1,249,000) life-years gained by ARV. DOTS treatment would have saved 1.63 million lives (1.09 - 2.17 million) when compared against no treatment, or 408,000 lives (265,000-551,000) when compared against non-DOTS treatment. ITN distributions in countries with stable endemic falciparum malaria were estimated to have achieved protection from malaria for 26 million of child-years at risk cumulatively, resulting in 130,000 (27,000-232,000) under-5 deaths prevented. Conclusions These results illustrate the scale of mortality effects that supported programs may have achieved in recent years, despite margins of uncertainty and covering only selected intervention components. Evidence-based evaluation of disease impact of the programs supported by the Global Fund with international and in-country partners must be strengthened using population-level data on intervention coverage and demographic outcomes, information on quality of services, and trends in disease burdens recorded in national health information systems.

Abstract Background An increasing number of malaria-endemic African countries are rapidly scaling up malaria prevention and treatment. To have an initial estimate of the impact of these efforts, time trends in health facility records were evaluated in selected districts in Ethiopia and Rwanda, where long-lasting insecticidal nets (LLIN) and artemisinin-based combination therapy (ACT) had been distributed nationwide by 2007. Methods In Ethiopia, a stratified convenience sample covered four major regions where (moderately) endemic malaria occurs. In Rwanda, two districts were sampled in all five provinces, with one rural health centre and one rural hospital selected in each district. The main impact indicator was percentage change in number of in-patient malaria cases and deaths in children < 5 years old prior to (2001–2005/6) and after (2007) nationwide implementation of LLIN and ACT. Results In-patient malaria cases and deaths in children < 5 years old in Rwanda fell by 55% and 67%, respectively, and in Ethiopia by 73% and 62%. Over this same time period, non-malaria cases and deaths generally remained stable or increased. Conclusion Initial evidence indicated that the combination of mass distribution of LLIN to all children < 5 years or all households and nationwide distribution of ACT in the public sector was associated with substantial declines of in-patient malaria cases and deaths in Rwanda and Ethiopia. Clinic-based data was a useful tool for local monitoring of the impact of malaria programmes.

Abstract Background HIV-related immune-suppression increases the risk of malaria (infection, disease and treatment failure) and probably the circulating parasite biomass, favoring the emergence of drug resistance parasites. Methods The additional malaria parasite biomass related to HIV-1 co-infection in sub-Saharan Africa was estimated by a mathematical model. Parasite biomass was computed as the incidence rate of clinical malaria episodes multiplied by the number of parasites circulating in the peripheral blood of patients at the time symptoms appear. A mathematical model estimated the influence of HIV-1 infection on parasite density in clinical malaria by country and by age group, malaria transmission intensity and urban/rural area. In a multivariate sensitivity analysis, 95% confidence intervals (CIs) were calculated using the Monte Carlo simulation. Results The model shows that in 2005 HIV-1 increased the overall malaria parasite biomass by 18.0% (95%CI: 11.6–26.9). The largest relative increase (134.9–243.9%) was found in southern Africa where HIV-1 prevalence is the highest and malaria transmission unstable. The largest absolute increase was found in Zambia, Malawi, the Central African Republic and Mozambique, where both malaria and HIV are highly endemic. A univariate sensitivity analysis shows that estimates are sensitive to the magnitude of the impact of HIV-1 infection on the malaria incidence rates and associated parasite densities. Conclusion The HIV-1 epidemic by increasing the malaria parasite biomass in sub-Saharan Africa may also increase the emergence of antimalarial drug resistance, potentially affecting the health of the whole population in countries endemic for both HIV-1 and malaria.

Supplemental Digital Content is Available in the Text. Background: Most countries use the Spectrum AIDS Impact Module (Spectrum-AIM), antenatal care routine HIV testing, and antiretroviral treatment data to estimate HIV prevalence among pregnant women. Nonrepresentative program data may lead to inaccurate estimates of HIV prevalence and treatment coverage for pregnant women. Setting: One hundred fifty-four countries and subnational locations across 126 countries. Methods: Using 2023 UNAIDS HIV estimates, we calculated 3 ratios: (1) HIV prevalence among pregnant women to all women 15–49 yrs (prevalence), (2) ART coverage before pregnancy to women 15–49 yrs ART coverage (ART prepregnancy), and (3) ART coverage at delivery to women 15–49 yrs ART coverage (PMTCT coverage). We developed an algorithm to identify and adjust inconsistent results within regional ranges in Spectrum-AIM, illustrated using Burkina Faso estimates. Results: In 2022, the mean regional ratio of prevalence among pregnant women to all women ranged from 0.68 to 0.95. ART coverage prepregnancy ranged by region from 0.40 to 1.22 times ART coverage among all women. Mean regional PMTCT coverage ratios ranged from 0.85 to 1.51. The prevalence ratio in Burkina Faso was 1.59, above the typical range 0.62–1.04 in western and central Africa. Antenatal clinics reported more PMTCT recipients than estimated HIV-positive pregnant women from 2015 to 2019. We adjusted inputted PMTCT program data to enable consistency of HIV prevalence among pregnant women from programmatic routine HIV testing at antenatal clinics with values typical for western and central Africa. Conclusions: These ratios offer Spectrum-AIM users a tool to gauge the consistency of their HIV prevalence and treatment coverage estimates among pregnant women with other countries in the region. [ABSTRACT FROM AUTHOR]

Introduction: Identifying strategies to further reduce AIDS‐related mortality requires accurate estimates of the extent to which mortality among people living with HIV (PLHIV) is due to AIDS‐related or non‐AIDS‐related causes. Existing approaches to estimating AIDS‐related mortality have quantified AIDS‐related mortality as total mortality among PLHIV in excess of age‐ and sex‐matched mortality in populations without HIV. However, recent evidence suggests that, with high antiretroviral therapy (ART) coverage, a growing proportion of excess mortality among PLHIV is non‐AIDS‐related. Methods: We searched Embase on 22/09/2023 for English language studies that contained data on AIDS‐related mortality rates among adult PLHIV and age‐matched comparator all‐cause mortality rates among people without HIV. We extracted data on the number and rates of all‐cause and AIDS‐related deaths, demographics, ART use and AIDS‐related mortality definitions. We calculated the proportion of excess mortality among PLHIV that is AIDS‐related. The proportion of excess mortality due to AIDS was pooled using random‐effects meta‐analysis. Results: Of 4485 studies identified by the initial search, eight were eligible, all from high‐income settings: five from Europe, one from Canada, one from Japan and one from South Korea. No studies reported on mortality among only untreated PLHIV. One study included only PLHIV on ART. In all studies, most PLHIV were on ART by the end of follow‐up. Overall, 1,331,742 person‐years and 17,471 deaths were included from PLHIV, a mortality rate of 13.1 per 1000 person‐years. Of these deaths, 7721 (44%) were AIDS‐related, an overall AIDS‐related mortality rate of 5.8 per 1000 person‐years. The mean overall mortality rate among the general population was 2.8 (95% CI: 1.8–4.0) per 1000 person‐years. The meta‐analysed percentage of excess mortality that was AIDS‐related was 53% (95% CI: 45–61%); 52% (43–60%) in Western and Central Europe and North America, and 71% (69–74%) in the Asia‐Pacific region. Discussion: Although we searched all regions, we only found eligible studies from high‐income countries, mostly European, so, the generalizability of these results to other regions and epidemic settings is unknown. Conclusions: Around half of the excess mortality among PLHIV in high‐income regions was non‐AIDS‐related. An emphasis on preventing and treating comorbidities linked to non‐AIDS mortality among PLHIV is required. [ABSTRACT FROM AUTHOR]

Introduction Sexually transmitted infections are among the most common communicable conditions and affect the health and lives of people worldwide. The World Health Organization (WHO) periodically generates estimates to gauge [...], Objective To generate estimates of the global prevalence and incidence of urogenital infection with chlamydia, gonorrhoea, trichomoniasis and syphilis in women and men, aged 15-49 years, in 2016. Methods For chlamydia, gonorrhoea and trichomoniasis, we systematically searched for studies conducted between 2009 and 2016 reporting prevalence. We also consulted regional experts. To generate estimates, we used Bayesian meta-analysis. For syphilis, we aggregated the national estimates generated by using Spectrum-STI. Findings For chlamydia, gonorrhoea and/or trichomoniasis, 130 studies were eligible. For syphilis, the Spectrum-STI database contained 978 data points for the same period. The 2016 global prevalence estimates in women were: chlamydia 3.8% (95% uncertainty interval, UI: 3.3-4.5); gonorrhoea 0.9% (95% UI: 0.7-1.1); trichomoniasis 5.3% (95% UI:4.0-7.2); and syphilis 0.5% (95% UI: 0.4-0.6). In men prevalence estimates were: chlamydia 2.7% (95% UI: 1.9-3.7); gonorrhoea 0.7% (95% UI: 0.5-1.1); trichomoniasis 0.6% (95% UI: 0.4- 0.9); and syphilis 0.5% (95% UI: 0.4-0.6). Total estimated incident cases were 376.4 million: 127.2 million (95% UI: 95.1-165.9 million) chlamydia cases; 86.9 million (95% UI: 58.6-123.4 million) gonorrhoea cases; 156.0 million (95% UI: 103.4-231.2 million) trichomoniasis cases; and 6.3 million (95% UI: 5.5-7.1 million) syphilis cases. Conclusion Global estimates of prevalence and incidence of these four curable sexually transmitted infections remain high. The study highlights the need to expand data collection efforts at country level and provides an initial baseline for monitoring progress of the World Health Organization global health sector strategy on sexually transmitted infections 2016-2021. Objectif Produire des estimations de la prevalence et de l&apos;incidence mondiales des infections urogenitales dues a la chlamydiose, a la gonorrhee, a la trichomonase et a la syphilis chez les femmes et les hommes de 15 a 49 ans, en 2016. Methodes Pour la chlamydiose, la gonorrhee et la trichomonase, nous avons systematiquement recherche les etudes menees entre 2009 et 2016 qui s&apos;interessaient a la prevalence. Nous avons egalement consulte des experts regionaux. Pour produire des estimations, nous avons eu recours a une meta-analyse bayesienne. Pour la syphilis, nous avons regroupe les estimations nationales obtenues a l&apos;aide de Spectrum-STI. Resultats Pour la chlamydiose, la gonorrhee et/ou la trichomonase, 130 etudes etaient eligibles. Pour la syphilis, la base de donnees de Spectrum-STI contenait 978 points de donnees pour la periode consideree. Les estimations de la prevalence mondiale en 2016 chez les femmes etaient les suivantes: chlamydiose 3,8% (intervalle d&apos;incertitude de 95%, II: 3,3-4,5); gonorrhee 0,9% (II 95%: 0,7-1,1); trichomonase 5,3% (II 95%: 4,0-7,2); et syphilis 0,5% (II 95%: 0,4-0,6). Chez les hommes, les estimations de la prevalence etaient les suivantes: chlamydiose 2,7% (II 95%: 1,9-3,7); gonorrhee 0,7% (II 95%: 0,5-1,1); trichomonase 0,6% (II 95%: 0,4-0,9); et syphilis 0,5% (II 95%: 0,4-0,6). Lincidence totale estimee etait de 376,4 millions de cas: 127,2 millions (II 95%: 95,1-165,9 millions) de cas de chlamydiose; 86,9 millions (II 95%: 58,6-123,4 millions) de cas de gonorrhee; 156,0 millions (II 95%: 103,4-231,2 millions) de cas de trichomonase; et 6,3 millions (II 95%: 5,5-7,1 millions) de cas de syphilis. Conclusion Les estimations mondiales de la prevalence et de l&apos;incidence de ces quatre infections sexuellement transmissibles guerissables restent elevees. Cette etude souligne la necessite d&apos;amplifier les efforts de collecte de donnees au niveau des pays et offre un point de reference pour suivre la progression de la Strategie mondiale du secteur de la sante contre les 1ST2016-2021 de l&apos;Organisation mondiale de la Sante. Objetivo Generar estimaciones de la prevalencia y la incidencia mundiales de la infeccion urogenital por clamidia, gonorrea, tricomoniasis y sifilis en mujeres y hombres de 15 a 49 anos de edad en 2016. Metodos Para la clamidia, la gonorrea y la tricomoniasis, se realizaron busquedas sistematicas de estudios realizados entre 2009 y 2016 que registrasen la prevalencia. Tambien se consulto a expertos regionales. Para generar estimaciones, se utilizo el metanalisis bayesiano. Para la sifilis, se anadieron las estimaciones nacionales generadas por el uso de Spectrum-STI. Resultados Para la clamidia, la gonorrea y/o la tricomoniasis, hubo 130 estudios que cumplian los criterios. Para la sifilis, la base de datos Spectrum-STI contenia 978 puntos de datos para el mismo periodo. Las estimaciones de prevalencia mundial en mujeres en 2016 fueron: clamidia 3,8 % (intervalo de incertidumbre, II, del 95 %: 3,3-4,5); gonorrea 0,9 % (II del 95 %: 0,7-1,1); tricomoniasis 5,3 % (II del 95 %: 4,0-7,2); y sifilis 0,5 % (II del 95 %: 0,4-0,6). Las estimaciones de prevalencia en hombres fueron: clamidia 2,7 % (intervalo de incertidumbre, II, del 95 %: 1,9-3,7); gonorrea 0,7 % (II del 95 %: 0,5-1,1); tricomoniasis 0,6 % (II del 95 %: 0,4-0,9); y sifilis 0,5 % (II del 95 %: 0,4-0,6). El total estimado de casos incidentes fue de 376,4 millones: 127,2 millones (II del 95 %: 95,1-165,9 millones) de casos de clamidia; 86,9 millones (II del 95 %: 58,6-123,4 millones) de casos de gonorrea; 156,0 millones (II del 95 %: 103,4-231,2 millones) de casos de tricomoniasis; y 6,3 millones (II del 95 %: 5,5-7,1 millones) de casos de sifilis. Conclusion Las estimaciones mundiales de la prevalencia y la incidencia de estas cuatro enfermedades de transmision sexual curables siguen siendo elevadas. El estudio destaca la necesidad de ampliar los esfuerzos de recopilacion de datos a nivel nacional y proporciona una base inicial para el seguimiento de los progresos de la Estrategia Mundial del Sector de la Salud de la Organizacion Mundial de la Salud sobre las ETS entre 2016 y 2021. [phrase omitted]

BackgroundTrials in Africa indicate that medical adult male circumcision (MAMC) reduces the risk of HIV by 60%. MAMC may avert 2 to 8 million HIV infections over 20 years in sub-Saharan Africa and cost less than treating those who would have been infected. This paper estimates the financial and human resources required to roll out MAMC and the net savings due to reduced infections.MethodsWe developed a model which included costing, demography and HIV epidemiology. We used it to investigate 14 countries in sub-Saharan Africa where the prevalence of male circumcision was lower than 80% and HIV prevalence among adults was higher than 5%, in addition to Uganda and the Nyanza province in Kenya. We assumed that the roll-out would take 5 years and lead to an MC prevalence among adult males of 85%. We also assumed that surgery would be done as it was in the trials. We calculated public program cost, number of full-time circumcisers and net costs or savings when adjusting for averted HIV treatments. Costs were in USD, discounted to 2007. 95% percentile intervals (95% PI) were estimated by Monte Carlo simulations.ResultsIn the first 5 years the number of circumcisers needed was 2 282 (95% PI: 2 018 to 2 959), or 0.24 (95% PI: 0.21 to 0.31) per 10,000 adults. In years 6-10, the number of circumcisers needed fell to 513 (95% PI: 452 to 664). The estimated 5-year cost of rolling out MAMC in the public sector was $919 million (95% PI: 726 to 1 245). The cumulative net cost over the first 10 years was $672 million (95% PI: 437 to 1,021) and over 20 years there were net savings of $2.3 billion (95% PI: 1.4 to 3.4).ConclusionA rapid roll-out of MAMC in sub-Saharan Africa requires substantial funding and a high number of circumcisers for the first five years. These investments are justified by MAMC's substantial health benefits and the savings accrued by averting future HIV infections. Lower ongoing costs and continued care savings suggest long-term sustainability.

Objective To assess whether the global target of halving tuberculosis (TB) mortality between 1990 and 2015 can be achieved and to conduct the first global assessment of the lives saved [...]

Author(s): Melanie M. Taylor 1,2,*, Eline Korenromp 3, Teodora Wi 1 Summary points WHO recommends 4 components of sexually transmitted infection (STI) surveillance at the country level: (1) clinical case [...]

A survey study was carried out to estimate the total number of nets and insecticide treated nets (ITNs) available at the house-hold level in sub-Saharan Africa at risk of malaria and the number needed to achieve the 80% coverage target for children younger than 5 years and pregnant women. To achieve the targeted ITN usage rates, numbers of ITNs available to African households must be dramatically increased which would require coordination among donor agencies, public health officials, net manufacturers, and existing distributions systems to ensure timely delivery and retreatment to achieve the agreed targets.

We assessed the impact of HIV-1 on malaria in the sub-Saharan African population. Relative risks for malaria in HIV-infected persons, derived from literature review, were applied to the HIV-infected population [...]

A modeling study is conducted to explore whether differences between the study populations could explain the magnitude of the differences in observed trial impacts and to predict the effectiveness of each intervention strategy in leach population. The findings support the hypothesis that differences between study populations and not intervention strategy were the main determinants of the contrasting HIV impacts in Rakai, Masaka, and Mwanza.