Serogroup-Specific Meningococcal Carriage by Age Group::A Systematic Review and Meta-Analysis

Objective Neisseria meningitidis carriage prevalence has known variation across the lifespan, but it is unclear whether carriage varies among meningococcal capsular groups. Therefore, we aimed to characterise group-specific meningococcal carriage by age group and world region from 2007 to 2016.Design Systematic review and meta-analysis.Data sources MEDLINE, Embase, Global Health Database, WHO Global Health Library, Web of Science, Current Contents Connects, China National Knowledge Infrastructure and Wanfang were systematically searched. Database searches were conducted through July 2018 and Google Scholar forward searches of included studies were conducted through August 2018. References of included studies and relevant conference abstracts were also searched to identify additional articles for inclusion.Eligibility criteria Studies were eligible for inclusion if they reported capsular group-specific meningococcal carriage in a healthy population of a specified age group and geographical region. For this review, only studies conducted between 2007 and 2016 were included.Data extraction and synthesis Data were independently extracted by two authors into Microsoft Access. Studies were assessed for risk of bias using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data. Studies eligible for inclusion in quantitative analyses by pre-specified age groups were pooled using random effects meta-analyses. Results are reported by capsular group, age group and WHO region. Where meta-analyses were not appropriate, study results were discussed narratively.Results 7511 articles were identified and 65 were eligible for inclusion. Adolescents and young adults were the focus of many studies (n=24), especially in the Americas and Europe. Studies from China and Africa, typically, included data from a wider age range. The overall carriage prevalence varied markedly by age group and region. Based on the available data, 21 studies were included in meta-analyses reporting serogroup carriage for: all ages in Africa, 18–24-year olds in the Americas, and 11–17 and 18–24-year olds in Europe. Capsular groups W, X, Y and ‘other’ (non-ABCWXY, including non-groupable) were the most prevalent in Africa, and 5–17-year olds had higher carriage prevalence than other age groups. ‘Other’ serogroups (11.5%, 95% CI 1.6% to 16.1%) were the most common among 18–24-year olds from the Americas. In Europe, 18–24-year old were carriers more frequently than 11–17-year olds, and groups B (5.0%, 95% CI 3.0% to 7.5%), Y (3.9%, 95% CI 1.3% to 7.8%) and ‘other’ (6.4%, 95% CI 3.1% to 10.8%) were the most commonly carried in the older age group.Conclusions Of the age groups included in the analysis, carriage patterns by age were similar across capsular groups within a region but differed between regions. Data gaps remain for age- and capsular group-specific carriage in many regions, especially in the Eastern Mediterranean and South-East Asia. As such, clear and robust conclusions about the variation of capsular group-specific carriage by age group and WHO region were unable to be determined

From curiosity to commodity: a review of the evolution of sachet drinking water in West Africa

The private sector continues to play an important role in filling local drinking water supply gaps across the Global South. In West Africa, a perfect storm of rapid population growth, infrastructure mismanagement, and globalization of consumer markets has resulted in the advent of an entire new industry around packaged water, primarily ‘sachet water’ sold in mechanically sealed plastic sleeves. Most local governments and international development agencies have historically perceived sachet water as a passing trend, but it has quickly become a primary drinking water source for the majority of households in many urban areas and continues to spread throughout the region and world. Sachet water is now an important component of regional water security, although with attendant issues related to governance, quality control, environmental pollution, and social justice. This paper reviews the seminal literature on sachet water in West Africa, with particular emphasis on Ghana and Nigeria, where most studies have focused. This review synthesizes governance issues, consumer and industry trends, and the latest on product quality in the literature from 2011 to 2016, with 2010 approximating an inflection point for the modernization of the industry. The ability of many West African nations to achieve universal access to safe drinking water may depend on their willingness to understand and incorporate the sachet water industry into an integrated drinking water platform. WIREs Water 2017, 4:e1206. doi: 10.1002/wat2.1206 This article is categorized under: Engineering Water > Planning Water Engineering Water > Sustainable Engineering of Water Human Water > Water Governance A typical 500‐mL sachet of drinking water sold in Accra, Ghana