Eline L. Korenromp

Measurement of trends in childhood malaria mortality in Africa: an assessment of progress toward targets based on verbal autopsy

Reduction of deaths associated with malaria in children is a primary goal of malaria control programmes in Africa, but there has been little discussion about how changes in mortality will be measured. This paper assesses recent historical changes in the contribution of malaria to child survival in Africa by examining data from demographic surveillance systems (DSS) in 25 mainly rural settings. The data were adjusted for the varying sensitivity and specificity of verbal autopsies (VA) in different ranges of malaria mortality and for varying parasite prevalences. Average malaria mortality in the DSS sites in west Africa was 7.8 per 1000 child-years between 1982 and 1998; the rate did not change significantly over this period. In the sites in east and southern Africa combined, malaria mortality was 6.5 per 1000 child-years between 1982 and 1989, but it increased to 11.9 per 1000 child-years between 1990 and 1998. All-cause child mortality and non-malaria mortality, by contrast, decreased significantly over time in both regions; consequently, the proportion of deaths due to malaria rose from 18% to 23% in west African sites and from 18% to 37% in east and southern African sites between 1982-89 and 1990-98. If malaria mortality fell at a rate consistent with the Roll Back Malaria target of halving malaria mortality by the year 2010, an individual DSS of a total population of 63 500 could with adequate VA adjustment detect this reduction after 7 years.

Initial evidence of reduction of malaria cases and deaths in Rwanda and Ethiopia due to rapid scale-up of malaria prevention and treatment

BackgroundAn 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.MethodsIn 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.ResultsIn-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.ConclusionInitial 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.

Monitoring mosquito net coverage for malaria control in Africa: possession vs. use by children under 5 years

Objectives To investigate the strengths and weaknesses of the indicators ‘proportion of households possessing mosquito net(s)’ and ‘proportion of children under 5 years of age who slept under a net the preceding night’ for monitoring malaria control.

Determinants of the impact of sexually transmitted infection treatment on prevention of HIV infection: A synthesis of evidence from the Mwanza, Rakai, and Masaka Intervention Trials

Community-randomized trials in Mwanza, Tanzania, and Rakai and Masaka, Uganda, suggested that population characteristics were an important determinant of the impact of sexually transmitted infection (STI) treatment interventions on incidence of human immunodeficiency virus (HIV) infection. We performed simulation modeling of HIV and STI transmission, which confirmed that the low trial impact in Rakai and Masaka could be explained by low prevalences of curable STI resulting from lower-risk sexual behavior in Uganda. The mature HIV epidemics in Uganda, with most HIV transmission occurring outside core groups with high STI rates, also contributed to the low impact on HIV incidence. Simulated impact on HIV was much greater in Mwanza, although the observed impact was larger than predicted from STI reductions, suggesting that random error also may have played some role. Of proposed alternative explanations, increasing herpetic ulceration due to HIV-related immunosuppression contributed little to the diminishing impact of antibiotic treatment during the Ugandan epidemics. The strategy of STI treatment also was unimportant, since syndromic treatment and annual mass treatment showed similar effectiveness in simulations of each trial population. In conclusion, lower-risk behavior and the mature HIV epidemic explain the limited impact of STI treatment on HIV incidence in Uganda in the 1990s. In populations with high-risk sexual behavior and high STI rates, STIs treatment interventions may contribute substantially to prevention of HIV infection.

Effects of human immunodeficiency virus infection on recurrence of tuberculosis after rifampin-based treatment: An analytical review

We reviewed 47 prospective studies of recurrence of pulmonary tuberculosis (TB) after cure to assess the influence of human immunodeficiency virus (HIV) infection and rifampin treatment. Multivariate regression revealed that the recurrence rate for HIV-uninfected persons increased with decreasing duration of therapy: it was 1.4 cases per 100 person-years for recipients of >or=7 months of rifampin therapy and 2.0 and 4.0 cases per 100 person-years for recipients of 5-6 and 2-3 months of rifampin therapy, respectively (trend P=.00014), over a mean follow-up duration of 34 months, at a TB incidence of 250 cases per 100,000 person-years. Relative risks of recurrence associated with HIV infection at these 3 treatment durations were 2.2, 2.1, and 3.4, respectively, with a significant interaction between HIV infection status and treatment duration (P=.025). The recurrence rate increased with the background TB incidence (P=.048), and it decreased over time since completion of treatment in HIV-uninfected but not in HIV-infected patients (overall trend, P=.00008; difference by HIV infection status, P=.025). In countries where HIV infection is endemic, TB recurrence may be reduced by administration of rifampin-based treatment for at least 6 months, in accordance with World Health Organization recommendations.

Relative risks and population attributable fraction of incident HIV associated with symptoms of sexually transmitted diseases and treatable symptomatic sexually transmitted diseases in Rakai District, Uganda

OBJECTIVES To assess the linkage of sexually transmitted disease (STD) symptoms and treatable STD to HIV incidence. DESIGN Analysis of a randomized trial of STD control for HIV prevention, Rakai, Uganda. METHODS Consenting adults 15-59 years of age were seen at 10-monthly home visits, interviewed regarding STD symptoms, and asked to provide samples for HIV and STD diagnoses. HIV incidence was determined in 8089 HIV-negative subjects over 10 457 person years. Adjusted rate ratios (RR) and 95% confidence intervals (CI) of HIV acquisition associated with genital ulcer disease (GUD) and discharge/dysuria were used to estimate the population attributable fraction (PAF) of HIV acquisition. HIV transmission risks associated with STD symptoms in HIV-positive partners of 167 HIV discordant couples and the numbers of sexual partners reported by HIV-positive subjects were used to estimate the PAF of HIV transmission attributable to STD. RESULTS HIV prevalence was 16%. The risk of HIV acquisition was increased with GUD (RR 3.14; CI 1.98-4.98) and in males with discharge/dysuria (RR 2.44; CI 1.17-5.12), but not in females with discharge/dysuria. The PAF of HIV acquisition was 9.5% (CI 2.8-15.8%) with any of the three STD symptoms. The PAF for GUD was 8.8% (CI 3.7-13.8), but only 8.2% of reported GUD was caused by treatable syphilis or chancroid . The PAF for discharge/dysuria in males was 6.7% (CI 1.1-13.8), but only 25% of symptomatic males had concurrent gonorrhea or chlamydial infection. No significant differences were seen in PAF between study treatment arms. The PAF of HIV transmission associated with STD symptoms in HIV-positive persons was indirectly estimated to be 10.4%. CONCLUSION In this mature, generalized HIV epidemic setting, most HIV seroconversion occurs without recognized STD symptoms or curable STD detected by screening. Therefore, syndromic management or other strategies of STD treatment are unlikely to substantially reduce HIV incidence in this population. However, STD is associated with significant HIV risk at the individual level, and STD management is needed to protect individuals.

Impact of malaria control on childhood anaemia in Africa - a quantitative review

Objective  To review the impact of malaria control on haemoglobin (Hb) distributions and anaemia prevalences in children under 5 in malaria‐endemic Africa.

Expanding ART for treatment and prevention of HIV in South Africa : estimated cost and cost-effectiveness 2011-2050

Background Antiretroviral Treatment (ART) significantly reduces HIV transmission. We conducted a cost-effectiveness analysis of the impact of expanded ART in South Africa. Methods We model a best case scenario of 90% annual HIV testing coverage in adults 15–49 years old and four ART eligibility scenarios: CD4 count <200 cells/mm3 (current practice), CD4 count <350, CD4 count <500, all CD4 levels. 2011–2050 outcomes include deaths, disability adjusted life years (DALYs), HIV infections, cost, and cost per DALY averted. Service and ART costs reflect South African data and international generic prices. ART reduces transmission by 92%. We conducted sensitivity analyses. Results Expanding ART to CD4 count <350 cells/mm3 prevents an estimated 265,000 (17%) and 1.3 million (15%) new HIV infections over 5 and 40 years, respectively. Cumulative deaths decline 15%, from 12.5 to 10.6 million; DALYs by 14% from 109 to 93 million over 40 years. Costs drop

Malaria attributable to the HIV-1 epidemic, sub-Saharan Africa.

504 million over 5 years and

Model-based evaluation of single-round mass treatment of sexually transmitted diseases for HIV control in a rural African population.

3.9 billion over 40 years with breakeven by 2013. Compared with the current scenario, expanding to <500 prevents an additional 585,000 and 3 million new HIV infections over 5 and 40 years, respectively. Expanding to all CD4 levels decreases HIV infections by 3.3 million (45%) and costs by