Meningococcal serogroups and surveillance: a systematic review and survey
JOURNAL OF GLOBAL HEALTH
2019; 9 (1): 010409
Meningococcal disease continues to be a global public health concern due to its epidemic potential, severity, and sequelae. The global epidemiological data on circulating meningococcal serogroups have never been reviewed concurrently with the laboratory capacity for meningococcal surveillance at the national level. We, therefore, aimed to conduct a country-level review of meningococcal surveillance, serogroup distribution, and vaccine use.We conducted a systematic literature review across six databases to identify studies (published January 1, 2010 to October 16, 2017) and grey literature reporting meningococcal serogroup data for the years 2010-2016. We performed independent random effects meta-analyses for serogroups A, B, C, W, X, Y, and other. We developed and circulated a questionnaire-based survey to surveillance focal points in countries (N = 95) with known regional bacterial meningitis surveillance programs to assess their surveillance capacity and summarized using descriptive methods.We included 173 studies from 59 countries in the final analysis. The distribution of meningococcal serogroups differed markedly between countries and regions. Meningococcal serogroups C and W accounted for substantial proportions of meningococcal disease in most of Africa and Latin America. Serogroup B was the predominant cause of meningococcal disease in many locations in Europe, the Americas, and the Western Pacific. Serogroup Y also caused many cases of meningococcal disease in these regions, particularly in Nordic countries. Survey responses were received from 51 countries. All countries reported the ability to confirm the pathogen in-country, while approximately 30% either relied on reference laboratories for serogrouping (N = 10) or did not serogroup specimens (N = 5). Approximately half of countries did not utilize active laboratory-based surveillance system (N = 22). Nationwide use of a meningococcal vaccine varied, but most countries (N = 36) utilized a meningococcal vaccine at least for certain high-risk population groups, in private care, or during outbreaks.Due to the large geographical variations in circulating meningococcal serogroups, each country should continue to be monitored for changes in major disease-causing serogroups in order to inform vaccine and control policies. Similarly, laboratory capacity should be appropriately scaled up to more accurately understand local epidemiology and disease burden, as well as the impact of vaccination programs.
View details for DOI 10.7189/jogh.09.010409
View details for Web of Science ID 000476640500034
View details for PubMedID 30603079
View details for PubMedCentralID PMC6304171
Serogroup-specific meningococcal carriage by age group: a systematic review and meta-analysis
2019; 9 (4): e024343
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.Systematic review and meta-analysis.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.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 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.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.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.CRD42017074671.
View details for DOI 10.1136/bmjopen-2018-024343
View details for Web of Science ID 000471157200052
View details for PubMedID 31005910
View details for PubMedCentralID PMC6500331
At-risk children with asthma (ARC): a systematic review
2018; 73 (9): 813–24
Asthma attacks are responsible for considerable morbidity and may be fatal. We aimed to identify and weight risk factors for asthma attacks in children (5-12 years) in order to inform and prioritise care.We systematically searched six databases (May 2016; updated with forward citations January 2017) with no language/date restrictions. Two reviewers independently selected studies for inclusion, assessed study quality and extracted data. Heterogeneity precluded meta-analysis. Weighting was undertaken by an Expert Panel who independently assessed each variable for degree of risk and confidence in the assessment (based on study quality and size, effect sizes, biological plausibility and consistency of results) and then achieved consensus by discussion. Assessments were finally presented, discussed and agreed at a multidisciplinary workshop.From 16 109 records, we included 68 papers (28 cohort; 4 case-control; 36 cross-sectional studies). Previous asthma attacks were associated with greatly increased risk of attack (ORs between 2.0 and 4.1). Persistent symptoms (ORs between 1.4 and 7.8) and poor access to care (ORs between 1.2 and 2.3) were associated with moderately/greatly increased risk. A moderately increased risk was associated with suboptimal drug regimen, comorbid atopic/allergic disease, African-American ethnicity (USA), poverty and vitamin D deficiency. Environmental tobacco smoke exposure, younger age, obesity and low parental education were associated with slightly increased risk.Assessment of the clinical and demographic features identified in this review may help clinicians to focus risk reduction management on the high-risk child. Population level factors may be used by health service planners and policymakers to target healthcare initiatives.CRD42016037464.
View details for DOI 10.1136/thoraxjnl-2017-210939
View details for Web of Science ID 000445107400006
View details for PubMedID 29871982
View details for PubMedCentralID PMC6109248
Meningococcal carriage in high-risk settings: A systematic review
INTERNATIONAL JOURNAL OF INFECTIOUS DISEASES
2018; 73: 109–17
Historically, semi-closed populations have had high rates of meningococcal carriage and have experienced recurrent outbreaks. As such, these high-risk groups are recommended for targeted vaccination in many countries.A systematic review of eight databases and Google Scholar forward citations was conducted to characterize serogroup-specific meningococcal carriage in university students, military personnel, and Hajj pilgrims from 2007 to 2016.A total of 7014 records were identified and 22 studies were included. Overall carriage ranged from 0.0% to 27.4% in Hajj pilgrims, from 1.5% to 71.1% in university students, and from 4.2% to 15.2% in military personnel. Among serogroups A, B, C, W, X, and Y, serogroup B was most prevalent in Hajj pilgrims, B and Y in university students, and B, C, and Y in military personnel. 'Other' serogroups were more prevalent in university students than Hajj pilgrims or military personnel. Risk factors for carriage varied by setting. Among Hajj pilgrims, a high endemicity in the country of origin increased the risk of carriage, while smoking, male sex, and frequently attending parties increased the carriage risk for university students. Similarly, smoking increased the carriage risk for professional soldiers. Data gaps remain for many regions.Preventative vaccination policies for high-risk groups should be based on current disease data in individual countries, supplemented by carriage data. Meningococcal carriage studies and disease surveillance are critical for determining the local epidemiology, populations responsible for disease transmission, and the need for targeted vaccination.
View details for DOI 10.1016/j.ijid.2018.05.022
View details for Web of Science ID 000440348300020
View details for PubMedID 29997031
Association of seasonal viral acute respiratory infection with pneumococcal disease: a systematic review of population-based studies
2018; 8 (4): e019743
Animal and in vitro studies suggest that viral acute respiratory infection (VARI) can predispose to pneumococcal infection. These findings suggest that the prevention of VARI can yield additional benefits for the control of pneumococcal disease (PD). In population-based studies, however, the evidence is not in accordance, possibly due to a variety of methodological challenges and problems in these studies. We aimed to summarise and critically review the methods and results from these studies in order to inform future studies.We conducted a systematic review of population-based studies that analysed the association between preceding seasonal VARI and subsequent PD. We searched MEDLINE, Embase and Global Health databases using tailored search strategies.A total of 28 studies were included. After critically reviewing the methodologies and findings, 11 studies did not control for seasonal factors shared by VARI and PD. This, in turn, could lead to an overestimation of the association between the two illnesses. One case-control study was limited by its small sample size (n case=13). The remaining 16 studies that controlled for seasonal factors suggested that influenza and/or respiratory syncytial virus (RSV) infections were likely to be associated with the subsequent occurrence of PD (influenza: 12/14 studies; RSV: 4/5 studies). However, these 16 studies were unable to conduct individual patient data-based analyses. Nevertheless, these studies suggested the association between VARI and subsequent PD was related to additional factors such as virus type and subtype, age group, comorbidity status, presentation of PD and pneumococcal serotype.Population-based studies do not give consistent support for an association between preceding seasonal VARI and subsequent PD incidence. The main methodological challenges of existing studies include the failure to use individual patient data, control for seasonal factors of VARI and PD, or include other factors related to the association (eg, virus, age, comorbidity and pneumococcal serotype).
View details for DOI 10.1136/bmjopen-2017-019743
View details for Web of Science ID 000435176700088
View details for PubMedID 29680810
View details for PubMedCentralID PMC5914779