Kazim Beebeejaun

Increase in Endemic Neisseria meningitidis Capsular Group W Sequence Type 11 Complex Associated With Severe Invasive Disease in England and Wales

BACKGROUND In England and Wales, the incidence of invasive meningococcal disease has been declining for more than a decade, but meningococcal group W (MenW) cases have been increasing since 2009. METHODS Public Health England conducts enhanced national surveillance of invasive meningococcal disease in England and Wales. Detailed clinical information was obtained for all laboratory-confirmed MenW cases diagnosed during 3 epidemiologic years (2010-2011 to 2012-2013), alongside whole-genome sequencing analysis of the clinical isolates. RESULTS The year-on-year increase in invasive MenW disease across all age groups since 2009-2010 was due to rapid endemic expansion of a single clone belonging to the sequence type 11 complex (cc11). In 2013-2014, MenW was responsible for 15% of all invasive meningococcal disease. All but 1 of the recent MenW:cc11 isolates were very closely related, consistent with recent clonal expansion. Clinical follow-up of all 129 MenW cases diagnosed during 2010-2011 to 2012-2013 revealed that most patients were previously healthy (n = 105 [81%]), had not travelled abroad prior to illness and the majority presented with septicemia (n = 63 [49%]), meningitis (n = 16 [12%]) or both (n = 21 [16%]); however, one-quarter had atypical presentations including pneumonia (n = 15 [12%]), septic arthritis (n = 9 [7%]), and epiglottitis/supraglottitis (n = 5 [4%]). Forty-eight (37%) required intensive care and 15 (12%) died. There was no association between infecting strain, clinical disease, or outcome. CONCLUSIONS The recent increase in invasive MenW disease in England and Wales is due to rapid endemic expansion of a single clone belonging to cc11 and is associated with severe disease with unusual clinical presentations. This increase will require careful monitoring in the coming years.

Effectiveness of Meningococcal B Vaccine against Endemic Hypervirulent Neisseriameningitidis W Strain, England

Serum samples from children immunized with a meningococcal serogroup B vaccine demonstrated potent serum bactericidal antibody activity against the hypervirulent Neisseria meningitidis serogroup W strain circulating in England. The recent introduction of this vaccine into the United Kingdom national immunization program should also help protect infants against this endemic strain.

Outbreak of hepatitis A associated with men who have sex with men (MSM), England, July 2016 to January 2017

Between July 2016 and January 2017, 37 confirmed cases of hepatitis A with two unique IA genotype strains primarily among men who have sex with men, were reported across eight areas in England and Northern Ireland. Epidemiological and laboratory investigations indicate that these strains may have been imported several times from Spain, with secondary sexual transmission in the United Kingdom. Local and national public health services are collaborating to control this ongoing outbreak.

Meningococcal Group W Disease in Infants and Potential Prevention by Vaccination.

To the Editor: We recently reported that postvaccination serum samples from infants immunized with a novel, protein-based multicomponent meningococcal serogroup B (MenB) vaccine (Bexsero; GlaxoSmithKline Vaccines, Verona, Italy) have bactericidal activity against the hypervirulent meningococcal group W (MenW) strain belonging to the sequence type (ST) 11 clonal complex (1). Historically, MenW has been a rare cause of invasive meningococcal disease (IMD), accounting for <5% of confirmed cases in England and Wales (2). Since 2009, MenW cases caused by this hypervirulent strain have rapidly increased in England (2). During the 2014–15 epidemiologic year (July 1–June 30), this capsular group accounted for 176 (24%) of 724 IMD cases in England (3). In response to this outbreak, in August 2015, the United Kingdom introduced an emergency adolescent conjugate vaccination program against meningococcal capsular groups ACW and Y. Over 2 years, the program aims to provide vaccine to all youth 13–18 years of age and to new university entrants <25 years of age. This program is expected to protect adolescents (25 of 176 [14%] MenW cases during 2014–15 were in those 15–19 years of age), and, by targeting youth with the highest carriage rates, to protect others through indirect (herd) protection, which has been consistently observed in vaccine programs, including that for meningococcal group C (4,5). Indirect protection associated with the adolescent immunization program will likely take several years to manifest (6).

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.

Safety of meningococcal group B vaccination in hospitalised premature infants.

Objectives To assess the risk of significant adverse events in premature infants receiving the novel 4-component group B meningococcal vaccine (4CMenB) with their routine immunisations at 2 months of age. Participants, design and setting In December 2015, Public Health England requested neonatal units across England to voluntarily participate in a national audit; 19 units agreed to participate. Anonymised questionnaires were completed for infants receiving 4CMenB alongside their routine immunisations. For comparison, a historical cohort of premature infants receiving their primary immunisations without 4CMenB or paracetamol prophylaxis was used. Main outcome measures Paracetamol use; temperature, cardiovascular, respiratory and neurological status before and after vaccination; and management and investigations postvaccination, including serum C reactive protein levels, infection screens and antibiotic use. Results Complete questionnaires were returned for 133 premature infants (<35 weeks’ gestation) who received their first dose of 4CMenB at 8 weeks of age, including 108 who received prophylactic paracetamol according to national recommendations. Overall, 7% (8/108) of infants receiving 4CMenB with paracetamol had fever (>38°C) after vaccination compared with 20% (5/25) of those receiving 4CMenB without paracetamol (P=0.06) and none of those in the historical cohort. There were no significant differences between cohorts in the proportion of infants with apnoea, bradycardia, desaturation and receiving respiratory support after vaccination. Conclusions 4CMenB does not increase the risk of serious adverse events in hospitalised premature infants. This audit supports the current national recommendations to offer 4CMenB with other routine vaccinations and prophylactic paracetamol to premature infants at their chronological age.