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Background: Meningococcal meningitis is a major cause of disease worldwide, with frequent epidemics particularly affecting an area of sub-Saharan Africa known as the "meningitis belt". Neisseria meningitidis group A (MenA) is responsible for major epidemics in Africa. Recently W-135 has emerged as an important pathogen. Currently, the strategy for control of such outbreaks is emergency use of meningococcal (MC) polysaccharide vaccines, but these have a limited ability to induce herd immunity and elicit an adequate immune response in infant and young children. In recent times initiatives have been taken to introduce meningococcal conjugate vaccine in these African countries. Currently there are two different types of MC conjugate vaccines at late stages of development covering serogroup A and W-135: a multivalent MC conjugate vaccine against serogroup A,C,Y and W-135; and a monovalent conjugate vaccine against serogroup A. We aimed to perform a structured assessment of these emerging meningococcal vaccines as a means of reducing global meningococal disease burden among children under 5 years of age. Methods: We used a modified CHNRI methodology for setting priorities in health research investments. This was done in two stages. In the first stage we systematically reviewed the literature related to emerging MC vaccines relevant to 12 criteria of interest. In Stage II, we conducted an expert opinion exercise by inviting 20 experts (leading basic scientists, international public health researchers, international policy makers and representatives of pharmaceutical companies). They answered questions from CHNRI framework and their "collective optimism" towards each criterion was documented on a scale from 0 to 100%. Results: For MenA conjugate vaccine the experts showed very high level of optimism (∼90% or more) for 7 out of the 12 criteria. The experts felt that the likelihood of efficacy on meningitis was very high (∼90%). Deliverability, acceptability to health workers, end users and the effect on equity were all seen as highly likely (~90%). In terms of the maximum potential impact on meningitis disease burden, the median potential effectiveness of the vaccines in reduction of overall meningitis mortality was estimated to be 20%; (interquartile range 20-40% and min. 8%, max 50 %). For the multivalent meningococcal vaccines the experts had similar optimism for most of the 12 CHNRI criteria with slightly lower optimism in answerability and low development cost criteria. The main concern was expressed over the cost of product, its affordability and cost of implementation. Conclusions: With increasing recognition of the burden of meningococcal meningitis, especially during epidemics in Africa, it is vitally important that strategies are taken to reduce the morbidity and mortality attributable to this disease. Improved MC vaccines are a promising investment that could substantially contribute to reduction of child meningitis mortality world-wide. [ABSTRACT FROM AUTHOR]

Background Our objective was to develop a methodology to estimate causes of death among children age 1-59 months in high child mortality countries without adequate vital registration (VR) systems. Methods We systematically reviewed community-based studies reporting at least two causes of death among children 1-59 months of age identified from published and unpublished sources. We included (i) studies conducted after 1979, (ii) for duration of 12 months or an exact multiple, (iii) with 525 deaths in children <5 years, (iv) each death represented once and (v) <25% of deaths due to unknown causes. A study-based multinomial logistic regression model was applied to country-level data to estimate causes of child death. Results Of the 216 studies reviewed, 81 were included in the analysis comprising 79 067 under-5 deaths from 25 countries. After adjusting for risk factors and intervention coverage, the estimated distribution of causes of deaths in children 1-59 months of age in sub-Saharan Africa and Southeast Asia was: pneumonia (21 and 31%), diarrhoea (25 and 31%), malaria (26 and 2%), injury (3 and 4%), meningitis (3 and 4%), measles (3 and 2%) and other causes (20 and 27%), respectively. Conclusion From studies reporting as few as two different causes of death, statistical modelling can be used to estimate the causes of child mortality for settings with incomplete VR. Pneumonia and diarrhoea remain the leading causes of death among children 1-59 months of age in sub-Saharan Africa and Southeast Asia. [ABSTRACT FROM AUTHOR]