Incidence Of Invasive Meningococcal Disease Research Articles

Epidemiological burden of meningococcal disease in Brazil: A systematic literature review and database analysis

ObjectivesThe aim of this study was to evaluate the epidemiological profile of invasive meningococcal disease (IMD) in Brazil, the first Latin American country to introduce the group C meningococcal conjugate vaccine (included in the vaccination schedule in 2010). MethodsA systematic review was conducted, covering the years 2005–2017, to identify epidemiological information on IMD and Neisseria meningitidis carriers in Brazil. Documents from the Brazilian Ministry of Health and two public databases were analyzed to determine annual incidence rates, absolute numbers of diagnosed cases, serogroups identified, the relative distribution of cases per serogroup, and the case fatality rate (CFR). ResultsSixteen studies were selected. The incidence rate ranged from 0.88 to 5.3 cases per 100000 inhabitants per year. According to secondary data, the annual incidence of IMD in 2015 was highest in males <1year old (7.1/100000). The number of diagnosed cases declined significantly over the years. In the literature, IMD showed a CFR from 20.0% to 50.0%, and a higher CFR for serogroup W (17.8%). Secondary data showed an absolute reduction in meningitis-attributable deaths between 2007 and 2015; however, the CFR remained stable (11.1% in 2007 and 8.4% in 2015). In 2015, serogroup W showed the highest CFR (24.1%), followed by serogroups C (19.2%), B (17.7%), and Y (14.3%). ConclusionsDespite a reduction in cases, the CFR remained stable and similar in the different age groups, even for disease caused by different serogroups. The highest CFR was found to be associated with serogroup W.

Poor adherence to population-based vaccination in two counties after meningococcal B:14:P1.7,16 outbreak: an illustration of the growing vaccine hesitancy in France

BackgroundNeisseria meningitidis is a virulent bacteria provoking outbreaks of invasive meningococcal disease (IMD) that authorities may try to control with population-based vaccinations. Such campaigns are most often thoroughly followed. We assess the response of poor adherence during a population-based vaccination after a meningococcal B:14:P1.7,16 outbreak. MethodsBetween July, 2012, and April, 2013, six cases including one fatality of invasive meningococcal disease related to N. meningitidis B:14:P1.7,16/ST32 were reported in two neighboring counties. A vaccination campaign with MenBVac® targeting 6911 inhabitants was implemented. People entering the vaccination schedule from January 2014 received 4CMenB. ResultsThe number of immunized patients proved to be low, with 1721 (24.1%) receiving at least one dose out of 5069 doses administered. However, the incidence of IMD in the zone dramatically fell, with only one purpura fulminans case in June 2014 with a good outcome. The campaign was stopped after 1 year and a 2-year monitoring period was implemented until June, 2016, with no new cases. ConclusionsThis outbreak probably self-terminated in a context of a low incidence of serogroup B IMD during 2014 in France. Poor adherence illustrates the growing vaccine hesitancy in France. Similar campaigns will have to be thoroughly planned and implemented in terms of timing, modalities of injections, and mass communication.

Observational Safety Study of Meningococcal Conjugate Vaccine Against Serogroups A, C, W and Y (Menactra) Used in Routine Healthcare Practice for Persons Aged 2 to 55 Years in Russian Federation

Although incidence of invasive meningococcal disease (IMD) in the Russian Federation is low, children younger 15 years of age are significantly affected. Serogroups A, B, and C are frequently implicated. The quadrivalent meningococcal diphtheria toxoid conjugate vaccine (MenACWY-D) is approved in Russia for immunization of individuals 9 months to 55 years of age. Goals . We evaluated the safety of a single dose of MenACWY-D administered to individuals 2–55 years of age in routine clinical practice in the Russian Federation. Materials and Methods . Using diary cards filled by participants or their parents, this prospective multicenter observational study quantified the occurrence of solicited injection site and systemic reactions up to 7 days after vaccination as well as unsolicited non-serious adverse events (AEs), and serious adverse events (SAEs) for 28 days. Results . The systemicrate of solicited injection site and systemic reactions during the 7-day observation period was 52.0% (95% CI: 41.8; 62.2). Rates of solicited injection site reactions and systemic reactions of any severity were 49% (95% CI: 38.9; 59.2) and 20% (95% CI: 12.7; 29.2), respectively. The rate of unsolicited AEs was 9% (95% CI: 4.2; 16.4). Rates of solicited grade 3 injection site and systemic reactions ranged between 1–3% and 0–1%, respectively. There were no unsolicited adverse reactions (ARs), SAEs, or deaths. Conclusions . These findings corroborate those of pre-licensure and post-registration studies and confirm the safety and good tolerability of MenACWY-D when used in routine clinical practice in individuals 2–55 years of age in the Russian Federation.

Epidemiology of two decades of invasive meningococcal disease in the Republic of Ireland: an analysis of national surveillance data on laboratory-confirmed cases from 1996 to 2016.

We examined the epidemiology of invasive meningococcal disease (IMD) in the Republic of Ireland (ROI) between epidemiological year (EY) 1996/1997 and EY2015/2016. Over the 20 EYs, 3707 cases were reported with annual incidence rates per 100 000 peaking at 11.6 in EY1999/2000, decreasing significantly to 1.5 in EY2015/2016. The highest disease burden was in infants and children &lt;5, whereas adults aged ⩾65 years experienced the highest case fatality ratio (CFR) of 15.7% but over the study period the median annual CFR remained low (4.4%). Meningococcal serogroup B (menB) dominated (78%), followed by menC (17%), menW (1%) and menY (1%). The incidence of menC IMD declined significantly in all age groups after menC vaccine introduction in 2000. MenB incidence also declined over the 20 EYs with decreasing trends in all age groups under 65, including an almost 50% decrease in infants over the final four EYs. IMD incidence in the ROI has declined, partly attributable to menC vaccination success, coupled with a spontaneous decline in menB. However, recent gradual increases in non-menB IMD and the introduction of vaccines targeting menB demand continued detailed surveillance to accurately monitor trends and to assess vaccine impact.

Declining Incidence of Invasive Meningococcal Disease in South Africa: 2003-2016.

Invasive meningococcal disease (IMD) is endemic to South Africa, where vaccine use is negligible. We describe the epidemiology of IMD in South Africa. IMD cases were identified through a national, laboratory-based surveillance program, GERMS-SA, from 2003-2016. Clinical data on outcomes and human immunodeficiency virus (HIV) statuses were available from 26 sentinel hospital sites. We conducted space-time analyses to detect clusters of serogroup-specific IMD cases. Over 14 years, 5249 IMD cases were identified. The incidence was 0.97 cases per 100 000 persons in 2003, peaked at 1.4 cases per 100 000 persons in 2006, and declined to 0.23 cases per 100 000 persons in 2016. Serogroups were confirmed in 3917 (75%) cases: serogroup A was present in 4.7% of cases, B in 23.3%, C in 9.4%; W in 49.5%; Y in 12.3%, X in 0.3%; Z in 0.1% and 0.4% of cases were non-groupable. We identified 8 serogroup-specific, geo-temporal clusters of disease. Isolate susceptibility was 100% to ceftriaxone, 95% to penicillin, and 99.9% to ciprofloxacin. The in-hospital case-fatality rate was 17% (247/1479). Of those tested, 36% (337/947) of IMD cases were HIV-coinfected. The IMD incidence in HIV-infected persons was higher for all age categories, with an age-adjusted relative risk ratio (aRRR) of 2.5 (95% confidence interval [CI] 2.2-2.8; P < .001) from 2012-2016. No patients reported previous meningococcal vaccine exposure. Patients with serogroup W were 3 times more likely to present with severe disease than those with serogroup B (aRRR 2.7, 95% CI 1.1-6.3); HIV coinfection was twice as common with W and Y diseases (aRRR W = 1.8, 95% CI 1.1-2.9; aRRR Y = 1.9, 95% CI 1.0-3.4). In the absence of significant vaccine use, IMD in South Africa decreased by 76% from 2003-2016. HIV was associated with an increased risk of IMD, especially for serogroup W and Y diseases.

Invasive meningococcal disease epidemiology and characterization of Neisseria meningitidis serogroups, sequence types, and clones; implication for use of meningococcal vaccines

ABSTRACTBackground and aims: Neisseria meningitidis (N. meningitidis) is a Gram-negative bacterium that can cause life-threatening invasive infections referred to as invasive meningococcal disease (IMD). In the last decade the incidence of IMD in Israel is about 1/100,000 population annually. We aimed to describe the epidemiology of IMD in Israel combining epidemiological data and characterization of N. meningitidis isolates.Methods: Invasive infection caused by N. meningitidis is a notifiable disease in Israel. Data were collected by epidemiological investigations and control measures were employed. Laboratory work-up included serogrouping, N. meningitides molecular characterization and whole-genome sequencing.Results: During 1998–2017, 1349 cases of IMD were notified in Israel (mean annual incidence rate 0.94/100,000). The peak incidence rates were observed in infants under 1 year of age (10.9/100,000). Case fatality rate was 9.7%. The majority of the N. meningitidis isolates were of serogroup B (67.9%). During 2007–2017, three clonal complexes (CC) 32, 41/44 and 23 (hyper-invasive clonal complexes) were the leading CC (61%). CC32 was the leading CC causing meningococcemia and mortality. In 2017, 35 isolates were tested for 4CMenB antigens variants; of the serogroup B isolates tested 46.7% showed a match to one or more antigens (fHbp or PorA:VR1), most were ST32 (CC32).Conclusions: Preliminary analysis based on limited number of samples suggests that the 4CMenB coverage would be about half the strains; further research is necessary. Integration of clinical, epidemiological and laboratory data is essential to support decision-making on the introduction of the novel MENB vaccines in Israel.

Interconnected clusters of invasive meningococcal disease due to Neisseria meningitidis serogroup C ST-11 (cc11), involving bisexuals and men who have sex with men, with discos and gay-venues hotspots of transmission, Tuscany, Italy, 2015 to 2016

In 2015 an increased incidence of invasive meningococcal disease due to serogroup-C (MenC) occurred in Tuscany, Italy. This led the Regional Health Authority of Tuscany to implement a reactive immunisation campaign and to launch an epidemiological field investigation aiming to address targeted immunisation interventions. In 2011–14, 10 MenC cases had been reported compared with 62 cases in 2015–16. The case fatality rate was 21% (n = 13) and 51 cases (82.3%) were confirmed as C:P1.5–1,10–8:F3–6:ST-11(cc11). Overall, 17 clusters were recognised. Six discos and four gay-venues were found to have a role as transmission-hotspots, having been attended by 20 and 14 cases in the 10 days before symptoms onset. Ten and three cases occurred, respectively, among men who have sex with men (MSM) and bisexual individuals, who were involved in 11 clusters. In addition, heterosexual cases (n = 5) attending gay-venues were also found. Secondary cases were not identified. Molecular typing indicated close relationship with MenC clusters recently described among gay, bisexual and other MSM in Europe and the United States, suggesting a possible international spread of the serogroup-C-variant P1.5–1,10–8:F3–6:ST-11(cc11) in this population-group; however, epidemiological links were not identified. In December 2016, a targeted vaccination campaign involving discos and lesbian, gay, bisexual, and transgender (LGBT) associations was implemented. During 2017, 10 cases of MenC occurred, compared with 32 and 30 cases reported in 2015 and 2016 respectively, suggesting the effectiveness of the reactive and targeted immunisation programmes.

Invasive meningococcal disease in Shanghai, China from 1950 to 2016: implications for serogroup B vaccine implementation

Serogroup B invasive meningococcal disease (IMD) is increasing in China, but little is known about the causative meningococci. Here, IMD and carriage isolates in Shanghai characterised and the applicability of different vaccines assessed. Seven IMD epidemic periods have been observed in Shanghai since 1950, with 460 isolates collected including 169 from IMD and 291 from carriage. Analyses were divided according to the period of meningococcal polysaccharide vaccine (MPV) introduction: (i) pre-MPV-A, 1965–1980; (ii) post-MPV-A, 1981–2008; and (iii) post-MPV-A + C, 2009–2016. Over this period, IMD incidence decreased from 55.4/100,000 to 0.71 then to 0.02, corresponding to successive changes in meningococcal type from serogroup A ST-5 complex (MenA:cc5) to MenC:cc4821, and finally MenB:cc4821. MenB IMD became predominant (63.2%) in the post-MPV-A + C period, and 50% of cases were caused by cc4821, with the highest incidence in infants (0.45/100,000) and a case-fatality rate of 9.5%. IMD was positively correlated with population carriage rates. Using the Bexsero Antigen Sequence Type (BAST) system, fewer than 25% of MenB isolates in the post-MPV-A + C period contained exact or predicted cross reactive matches to the vaccines Bexsero, Trumenba, or an outer membrane vesicle (OMV)-based vaccine, NonaMen. A unique IMD epidemiology was seen in China, changing periodically from epidemic to hyperepidemic and low-level endemic disease. At the time of writing, MenB IMD dominated IMD in Shanghai, with isolates potentially beyond coverage with licenced OMV- and protein-based MenB vaccines.

Epidemiology of vaccine-preventable diseases in Japan: considerations for pre-travel advice for the 2019 Rugby World Cup and 2020 Summer Olympic and Paralympic Games.

IntroductionIn 2019 and 2020, Japan will host two international sporting events estimated to draw a combined 22 million visitors. Mass gatherings like these ones increase the risk of spread of infectious disease outbreaks and international transmission. Pre-travel advice reduces that risk.MethodsTo assist ministries of health and related organizations in developing pre-travel advice, we summarized national surveillance data in Japan (2000–2016, to the extent available) for rubella, invasive pneumococcal disease, measles, non-A and non-E viral hepatitis, hepatitis A, invasive Haemophilus influenzae disease, tetanus, typhoid fever, invasive meningococcal disease, Japanese encephalitis, influenza, varicella, mumps and pertussis by calculating descriptive statistics of reported cases and reviewing trends. (See Annex A for details of reviewed diseases.)ResultsOur findings showed notable incidences of rubella (1.78 per 100 000 person-years), influenza (243.5 cases per sentinel site), and mumps (40.1 per sentinel site); seasonal increases for influenza (November–May) and Japanese encephalitis (August–November); and a geographical concentration of Japanese encephalitis in western Japan. Measles cases decreased from 11 013 in 2008 to 35 in 2015, but outbreaks (n = 165 cases) associated with importation occurred in 2016. Though invasive meningococcal disease incidence was only 0.03 per 100 000, international transmission occurred at a mass gathering in Japan in 2015.DiscussionMinistries of health and related organizations should use these findings to develop targeted pre-travel advice for travellers to the 2019 Rugby World Cup and the 2020 Summer Olympic and Paralympic Games, especially for mumps, measles, rubella, influenza, and meningitis. Travellers with increased exposure risk should also be advised about hepatitis A and Japanese encephalitis.

Epidemiology, clinical presentation, risk factors, intensive care admission and outcomes of invasive meningococcal disease in England, 2010–2015

The epidemiology of invasive meningococcal disease (IMD) is constantly changing as new strains are introduced into a population and older strains are removed through vaccination, population immunity or natural trends. Consequently, the clinical disease associated with circulating strains may also change over time. In England, IMD incidence has declined from 1.8/100,000 in 2010/2011 to 1.1/100,000 in 2013/2014, with a small increase in 2014/2015 to 1.3/100,000. Between 01 January 2011 and 30 June 2015, MenB was responsible for 73.0% (n = 2489) of 3411 laboratory-confirmed IMD cases, followed by MenW (n = 371, 10.9%), MenY (n = 373, 10.9%) and MenC (n = 129, 3.8%); other capsular groups were rare (n = 49, 1.4%). Detailed questionnaires were completed for all 3411 laboratory-confirmed cases. Clinical presentation varied by capsular group and age. Atypical presentations were uncommon (244/3411; 7.2%), increasing from 1.2% (41/3411) in children to 3.5% (120/3411) in older adults. Known IMD risk factors were rare (18/3411; 0.5%) and included complement deficiency (n = 11), asplenia (n = 6) or both (n = 1). Nearly a third of cases required intensive care (1069/3411; 31.3%), with rates highest in adults. The 28-day CFR was 6.9% (n = 237), with the lowest rates in 0–14 year-olds (85/1885, 4.5%) and highest among 85+ year-olds (30/94, 31.9%). These observations provide a useful baseline for the current burden of IMD in a European country with enhanced national surveillance.

Clinical presentation of invasive disease caused by Neisseria meningitidis serogroup Y in Sweden, 1995 to 2012.

Over the period 1995-2012, the incidence of invasive meningococcal disease (IMD) caused by Neisseria meningitidis serogroup Y (NmY) increased significantly in Sweden. This is mainly due to the emergence of a predominant cluster named strain type YI subtype 1, belonging to the ST-23 clonal complex (cc). The aim of this study was to examine the clinical picture of patients with invasive disease caused by NmY and to analyse whether the predominant cluster exhibits certain clinical characteristics that might explain the increased incidence. In this retrospective observational study, the medical records available from patients with IMD caused by Nm serogroup Y in Sweden between 1995 and 2012 were systematically reviewed. Patient characteristics, in-hospital findings and outcome were studied and differences between the dominating cluster and other isolates were analysed. Medical records from 175 of 191 patients were retrieved. The median age was 62 years. The all-cause mortality within 30 days of admission was 9% (15/175) in the whole material; 4% (2/54) in the cohort with strain type YI subtype 1 and 11% (12/121) among patients with other isolates. Thirty-three per cent of the patients were diagnosed with meningitis, 19% with pneumonia, 10% with arthritis and 35% were found to have bacteraemia but no apparent organ manifestation. This survey included cases with an aggressive clinical course as well as cases with a relatively mild clinical presentation. There was a trend towards lower mortality and less-severe disease in the cohort with strain type YI subtype 1 compared with the group with other isolates.

Cost-effectiveness of alternate strategies for childhood immunization against meningococcal disease with monovalent and quadrivalent conjugate vaccines in Canada

BackgroundPublic health programs to prevent invasive meningococcal disease (IMD) with monovalent serogroup C meningococcal conjugate vaccine (MCV-C) and quadrivalent meningococcal conjugate vaccines (MCV-4) in infancy and adolescence vary across Canadian provinces. This study evaluated the cost-effectiveness of various vaccination strategies against IMD using current and anticipated future pricing and recent epidemiology.MethodsA cohort model was developed to estimate the clinical burden and costs (CAN$2014) of IMD in the Canadian population over a 100-year time horizon for three strategies: (1) MCV-C in infants and adolescents (MCV-C/C); (2) MCV-C in infants and MCV-4 in adolescents (MCV-C/4); and (3) MCV-4 in infants (2 doses) and adolescents (MCV-4/4). The source for IMD incidence was Canadian surveillance data. The effectiveness of MCV-C was based on published literature. The effectiveness of MCV-4 against all vaccination regimens was assumed to be the same as for MCV-C regimens against serogroup C. Herd effects were estimated by calibration to estimates reported in prior analyses. Costs were from published sources. Vaccines prices were projected to decline over time reflecting historical procurement trends.ResultsOver the modeling horizon there are a projected 11,438 IMD cases and 1,195 IMD deaths with MCV-C/C; expected total costs are $597.5 million. MCV-C/4 is projected to reduce cases of IMD by 1,826 (16%) and IMD deaths by 161 (13%). Vaccination costs are increased by $32 million but direct and indirect IMD costs are projected to be reduced by $46 million. MCV-C/4 is therefore dominant vs. MCV-C/C in the base case. Cost-effectiveness of MCV-4/4 was $111,286 per QALY gained versus MCV-C/4 (2575/206 IMD cases/deaths prevented; incremental costs $68 million).ConclusionsIf historical trends in Canadian vaccines prices continue, use of MCV-4 instead of MCV-C in adolescents may be cost-effective. From an economic perspective, switching to MCV-4 as the adolescent booster should be considered.

Characteristics and changes in invasive meningococcal disease epidemiology in France, 2006–2015

This work aimed to describe the epidemiology of invasive meningococcal disease (IMD) in France, 2006-2015, including group- and genotype-specific disease burden, incidence trends before and after introduction of meningococcal C conjugate vaccines (MCCV) in 2010, and factors influencing the case fatality rate. Mandatory notification data on incidence and IMD case characteristics were used. Genotyping of invasive strains and whole genome sequencing were performed by the French National Reference Center. Vaccination coverage was estimated from the National Health Insurance Information System's reimbursement data. The decrease in annual IMD incidence rates (per 100,000 inhabitants) from 1.23 in 2006 to 0.78 in 2016 was mainly related to the decrease in group B IMD. Group C incidence decreased from 0.29 in 2006 to 0.13 in 2010 but increased thereafter in age groups not targeted by MCCV. From 2010 onwards, MCCV coverage gradually increased but remained below 25% in 15-19 year-olds in 2015. Age, clinical presentation and, to a lesser extent, clonal complex 11 were the most significant factors determining mortality. The limited impact of vaccination on group C IMD incidence may be explained by the emergence of a new epidemic cycle in 2011 and the low vaccination coverage rates among adolescents and young adults.

Multicomponent meningococcal B vaccination (4CMenB) of adolescents and college students in the United States.

Meningococcal disease is rare, easily misdiagnosed, and potentially deadly. Diagnosis in the early stages is difficult and the disease often progresses extremely rapidly. In North America, the incidence of invasive meningococcal disease (IMD) is highest in infants and young children, with a secondary peak in adolescents, a population predominantly responsible for the carriage of disease. Neisseria meningitidis serogroup B (MenB) accounts for a large proportion of meningococcal disease in North America, with documented outbreaks in three universities in the United States (US) during 2008–2013. Vaccination is the most effective way to protect against this aggressive disease that has a narrow timeframe for diagnosis and treatment. 4CMenB is a multi-component vaccine against MenB which contains four antigenic components. We describe in detail the immunogenicity and safety profile of 4CMenB based on results from four clinical trials; the use of 4CMenB to control MenB outbreaks involving vaccination at two US colleges during outbreaks in 2013–2014; and the use of 4CMenB in a Canadian mass vaccination campaign to control the spread of MenB disease. We discuss the reasons why adolescents should be vaccinated against MenB, by examining both the peak in disease incidence and carriage. We consider whether herd protection may be attained for MenB, by discussing published models and comparing with meningitis C (MenC) vaccines. In conclusion, MenB vaccines are now available in the US for people aged 10–25 years, representing an important opportunity to reduce the incidence of IMD in the country across the whole population, and more locally to combat MenB outbreaks.

Serogroup and Clonal Characterization of Czech Invasive Neisseria meningitidis Strains Isolated from 1971 to 2015.

BackgroundThis study presents antigenic and genetic characteristics of Neisseria meningitidis strains recovered from invasive meningococcal disease (IMD) in the Czech Republic in 1971–2015.Material and MethodsA total of 1970 isolates from IMD, referred to the National Reference Laboratory for Meningococcal Infections in 1971–2015, were studied. All isolates were identified and characterized by conventional biochemical and serological tests. Most isolates (82.5%) were characterized by multilocus sequence typing method.ResultsIn the study period 1971–2015, the leading serogroup was B (52.4%), most often assigned to clonal complexes cc32, cc41/44, cc18, and cc269. A significant percentage of strains were of serogroup C (41.4%), with high clonal homogeneity due to hyperinvasive complex cc11, which played an important role in IMD in the Czech Republic in the mid-1990s. Serogroup Y isolates, mostly assigned to cc23, and isolates of clonally homogeneous serogroup W have also been recovered more often over the last years.ConclusionThe incidence of IMD and distribution of serogroups and clonal complexes of N. meningitidis in the Czech Republic varied over time, as can be seen from the long-term monitoring, including molecular surveillance data. Data from the conventional and molecular IMD surveillance are helpful in refining the antimeningococcal vaccination strategy in the Czech Republic.

Molecular characterization of a collection of Neisseria meningitidis isolates from Croatia, June 2009 to January 2014.

In the last decade, the incidence of invasive meningococcal disease (IMD) in Croatia remained stable at approximately 1 case per 100 000 inhabitants, affecting mainly children aged ≤5 years. We report the molecular characterization of meningococci causing IMD occurring from June 2009 to January 2014 in Croatia. Genomic DNA from 50 clinical isolates was analysed for serogroup, multilocus sequence typing and allele type of the two outer membrane protein genes, porA and the iron-regulated fetA. Furthermore, 22 of them were characterized by using whole-genome sequencing to define the meningococcal vaccine four-component meningococcal serogroup B (4CMenB) antigen genes factor H-binding protein (fHbp), Neisseria heparin-binding antigen (nhba) and Neisseria adhesin A (nadA) and the antimicrobial target resistance genes for penicillin (penicillin binding protein 2, penA), ciprofloxacin (DNA gyrase subunit A, gyrA) and rifampicin (β-subunit of RNA polymerase, rpoB). The Etest was used to phenotypically determine the antimicrobial susceptibility of isolated meningococci. The main serogroup/clonal complex combinations were MenB cc41/44, MenC/cc11, MenW/cc174 and MenY/cc23. PorA P1.7-2, FetA F5-5 and F1-5 were the most represented through the serogroups. Meningococci with decreased susceptibility to penicillin (38.9 %) and one strain resistant to ciprofloxacin were identified. Forty-two percent of MenB showed the presence of at least one of the 4CMenB vaccine antigens (fHbp, NHBA, NadA and PorA). Our findings highlight the genetic variability of meningococci causing IMD in Croatia, especially for the serogroup B. Molecular-based characterization of meningococci is crucial to enhance IMD surveillance and to better plan national immunization programmes.

National surveillance for meningococcal disease in Japan, 1999–2014

We summarize the epidemiology of Japanese meningococcal disease with serogroup distribution. One hundred seventy-eight meningococcal meningitis cases were reported from April 1999 to March 2013 to the national surveillance system. From April 2013, bacteremia was added to the condition of reporting invasive meningococcal disease (IMD). Since then, 59 IMD cases were reported by the end of 2014. Approximately two thirds of the cases were male and the median age was 56years (range: 0–93years). Only 3% of the cases were <5years old. One third of reported cases were meningitis and the others were bacteremia. The annual incidence (2014) for IMD was 0.028 per 100,000 and case fatality rate (CFR) was 19%. Serogroup Y (42%) was the most dominant serogroup, followed by C (12%), B (7%) and W (3%). Even though the number of reported cases has increased after the amendment of reporting requirements, the incidence of IMD is still low in Japan. Underreporting may play a role in this low incidence. Improving on the limitations of the surveillance system is necessary to capture the true epidemiology and accurate serogroup distribution of IMD cases in Japan, which is essential for making effective recommendations on newly licensed vaccine.

Meningococcal Vaccinations.

Neisseria meningitidis, a gram-negative diplococcal bacterium, is a common asymptomatic nasopharyngeal colonizer that may infrequently lead to invasive disease in the form of meningitis or bacteremia. Six serogroups (A, B, C, W, X and Y) are responsible for the majority of invasive infections. Increased risk of disease occurs in specific population groups including infants, adolescents, those with asplenia or complement deficiencies, and those residing in crowded living conditions such as in college dormitories. The incidence of invasive meningococcal disease varies geographically with some countries (e.g., in the African meningitis belt) having both high endemic disease rates and ongoing epidemics, with annual rates reaching 1000 cases per 100,000 persons. Given the significant morbidity and mortality associated with meningococcal disease, it remains a major global health threat best prevented by vaccination. Several countries have implemented vaccination programs with the selection of specific vaccine(s) based on locally prevalent serogroup(s) of N. meningitidis and targeting population groups at highest risk. Polysaccharide meningococcal vaccines became available over 40 years ago, but are limited by their inability to produce immunologic memory responses, poor immunogenicity in infants/children, hyporesponsiveness after repeated doses, and lack of efficacy against nasopharyngeal carriage. In 1999, the first meningococcal conjugate vaccines were introduced and have been successful in overcoming many of the shortcomings of polysaccharide vaccines. The implementation of meningococcal conjugate vaccination programs in many areas of the world (including the massive campaign in sub-Saharan Africa using a serogroup A conjugate vaccine) has led to dramatic reductions in the incidence of meningococcal disease by both individual and population protection. Progressive advances in vaccinology have led to the recent licensure of two effective vaccines against serogroup B [MenB-4C (Bexsero) and MenB-FHbp (Trumenba)]. Overall, the evolution of novel meningococcal vaccines and the effective implementation of targeted vaccination programs has led to a substantial decrease in the burden of disease worldwide representing a major public health accomplishment.

Rising incidence of invasive meningococcal disease caused by Neisseria meningitidis serogroup W in Victoria.

Rising incidence of invasive meningococcal disease caused by Neisseria meningitidis serogroup W in Victoria.

Increased incidence of invasive meningococcal disease of serogroup C / clonal complex 11, Tuscany, Italy, 2015 to 2016.

We report an increase of serogroup C Neisseria meningitidis invasive meningococcal disease in Tuscany. From January 2015 to end February 2016, 43 cases were reported, among which 10 were fatal, compared to two cases caused by serogroup C recorded in 2014 and three in 2013. No secondary cases occurred. Thirty-five strains belonged to C:P1.5-1,10-8:F3-6:ST-11(cc11). Control measures have been adopted and immunisation campaigns implemented. Studies on risk factors and carriage are ongoing.