Research and analysis

HPR volume 10 issue 37: news (28 October)

Updated 16 December 2016

1. Impact of MenB infant vaccination programme in England

At the end of the first season following the introduction of a multicomponent, group B meningococcal (MenB) vaccine into the UK infant immunisation programme, an assessment of vaccine effectiveness and impact on invasive disease in England has provided reassuring results.

In a Lancet paper presenting the results of a national cohort study of invasive meningococcal disease (IMD) diagnosed in England between September 2015 and June 2016, PHE scientists report a significant reduction in IMD cases among vaccine-eligible infants within 10 months of the vaccine’s introduction [1]. Compared with the pre-vaccine period, the study suggests a 50% reduction in incidence of IMD was achieved in the vaccine-eligible cohort.

The UK was the first country to introduce the MenB vaccine into a publicly-funded programme in September 2015, ahead of the 2015/16 season. Infants were offered the 4CMenB vaccine at two and four months along with their other routine vaccinations, followed by a booster at 12 months. Infants attending their routine 3- and 4-month routine immunisations were also opportunistically offered the vaccine when it was first introduced. The two-dose infant schedule was found to be 83% effective against all MenB cases, irrespective of whether the responsible MenB strain was preventable by the vaccine.

The authors of the Lancet paper note that their findings should provide reassurance to clinicians, immunisers and policy makers that the vaccine is effective in infants.

1.1 Reference

1. “Effectiveness and impact of a reduced infant schedule of 4CmenB vaccine against group B meningococcal disease in England: a national cohort study”, Lancet online, 27 October 2016.

2. Legionnaires’ disease in England and Wales: annual report for 2015

The latest annual report on Legionnaires Disease in England and Wales describes the epidemiological features of microbiologically-confirmed, reported cases with symptom onset dates falling in 2015 [1].

A total of 382 confirmed cases of were reported in 2015, half of which were considered to have encountered the source of infection from within the community; a fall of 6.2% compared to 2014. There continues to be an increase in the proportion of cases associated with travel abroad: from 42.0% in 2014 to 46.3% in 2015. Although the highest number of travel-associated cases were associated with travel to Spain during their incubation period, travel to Thailand and the United Arab Emirates accounted for the highest rates of infection at 41.7 and 41.0 cases per million visits, respectively.

The crude case fatality rate (CFR) for Legionnaires Disease in England and Wales in 2015 was 6.8%, the lowest rate ever recorded since records began in 1980. The crude CFR increases with age to a rate of 15.3% in those aged 70 years and over.

2.1 Reference

1. PHE (26 October 2016). Legionnaires’ disease in England and Wales: 2015.

3. Mosquito finding underlines importance of UK surveillance systems

The south-east Asian forest mosquito Aedes albopictus – whose presence in Europe was first reported in Albania in 1979 and subsequently in 28 other European countries – was detected for the first time in the UK in September [1]. Its detection by PHE routine surveillance procedures has significance in view of Aedes albopictus being a potential vector for transmission of infections – chikungunya and dengue fever in particular – prevalent only in semi-tropical or tropical climates [2].

Contrary to UK media reports circulating in recent weeks, there is no evidence to date that the species is a vector of Zika virus (ZIKV) and its detection has no immediate significance for the current UK ZIKV risk assessment.

Aedes albopictus is nevertheless a particular biting nuisance in many European countries – including Italy, southern France, Spain, and the Adriatic coasts of Croatia – and climate models have shown the UK is suitable for the development and maintenance of populations of this species [2]. The species also has medical significance as it is a proven vector of chikungunya virus (CHIKV) and has been the primary vector of cases on La Reunion Island, in Italy, and in France. It is also a vector of Dengue virus (DENV) and has been responsible for locally-acquired cases in Croatia and France.

Ae. albopictus eggs have been moved around the world primarily in shipments of used tyres; once established in a new locality, adult mosquitoes are moved along highway systems in vehicles.

Surveillance for invasive mosquitoes is conducted by PHE’s Medical Entomology group, in collaboration with Port and Environmental Health Officers, and Edge Hill University [1]. Traps are run at 31 ports and airports, including British forces bases in Cyprus and Gibraltar. Early detection of this species allows control strategies to be implemented, with the aim of preventing the establishment of exotic mosquito vectors. PHE also monitors traps at service stations in south-east England, with the aim of detecting mosquitoes brought in via vehicles arriving at ferry and Eurotunnel ports, and at used tyre importers.

In September 2016, PHE detected 37 eggs at one trap in a service station in south-east England, evidence that at least one female mosquito was imported, probably via vehicular traffic from the continent. PHE conducted enhanced surveillance in the locality, which included the service station, the M20, high-speed rail link, a farm and associated arable fields, and small number of residential properties. No further evidence of the species has so far been found. The local authority implemented a control strategy targeting all container habitats with 300 metres. PHE will conduct further enhanced surveillance in the spring at the site.

The finding of Ae. albopictus in the UK underlines the importance of a comprehensive surveillance system. In addition to active surveillance, PHE runs a mosquito reporting scheme, and this “passive” surveillance will be crucial to identify further occurrences of this species in years to come. As it moves northward in France, more frequent incursions of Ae. albopictus are to be expected, particularly in relation to vehicle movements from the continent. The recent finding also identifies the need for a robust control strategy that can be implemented within hours of a finding, to ensure the species does not spread further.

3.1 References

1. PHE webpages. Mosquito: nationwide surveillance.
2. PHE Public Health Matters blog (8 January 2016). Vector-borne diseases in the 21st century.

4. Vaccine-preventable disease reports in this issue of HPR

The following two vaccine-preventable disease reports are published in this issue of HPR. The links below are to the relevant webpage collections:

• Invasive meningococcal disease (laboratory reports in England): 2015/2016 annual data by epidemiological year
• Laboratory reports of hepatitis A and C (England and Wales): April to June 2016.

5. New publication: Health Protection: Principles and Practice

A new, multi-author practical guide and textbook, Health Protection: Principles and Practice, covering the principles of health protection and adopting a modern, all-hazards approach, has been published by OUP [1].

After introducing the essential principles of health protection work, and reviewing emerging health protection issues, the book considers responses to real incidents through a combination of case studies and checklists (in appendices) covering more than 180 common or important topics in health protection practice. The target audience is health protection practitioners, other public health professionals and postgraduate students. No prior medical or clinical knowledge is assumed in any chapter.

The 38 contributors are all UK-based practitioners active in the field, or in closely related fields, the majority currently working within Public Health England’s health protection directorate: either as medical consultants, field epidemiology specialists, or Health Protection Centre staff, or working within CRCE or in emergency preparedness functions.

Although the textbook’s scope mirrors exactly the range of responsibilities of PHE’s health protection directorate, it is likely to be of value to a wider, global audience because of its “all-hazards” scope: it covers communicable disease surveillance/control, emergency preparedness, resilience and response, and environmental public health – activities that in many countries are the responsibility of different organisations (as was the case in England prior to the creation of the Health Protection Agency in 2003).

In a foreword, Professor Paul Cosford, PHE director of health protection and medical director, has welcomed the publication: “This book is the first to describe the [health protection] functions in a single dedicated textbook … taking an inclusive, all-hazards approach.… [and] recognition of health protection as a distinct discipline”.

5.1 Reference

1. Health Protection: Principles and Practice, edited by Sam Ghebrehewet, Alex G. Stewart, David Baxter, Paul Shears, David Conrad and Merav Kliner (450 page, ISBN-978-0-19-874547-1, RRP £34.99), is published by Oxford University Press.