Corporate report

PHE research 2018 to 2019: annual review

Updated 25 May 2021

During 2018 to 2019, Public Health England (PHE) continued to enhance its status as an excellent research organisation, participating in a wide range of studies. This resulted in 890 peer-reviewed articles, of which many published in the world’s most acclaimed scientific and clinical journals.

This report profiles some of the research carried out by PHE, often in partnership with academics, clinicians and field researchers from around the world. Examples include research from some of the Health Protection Research Units, which are partnerships between PHE and academic centres of excellence, funded through the National Institute for Health Research (NIHR).

This report shows how our research has yielded evidence that underpins the development of programmes to protect and improve public health and demonstrates how PHE discharges its responsibilities as a public health organisation.

Findings published by PHE with our collaborators during the year include evaluations of changes to the UK vaccination programme, analysis of the continued development of major public health campaigns, such as Antibiotic Guardian and the NHS Diabetes Prevention Programme, and investigations of possible risks to health from a range of environmental issues.

Our results show the efficiency of frontline use of data analysis techniques, including our researchers’ work related to data on novel pathogens and the contribution of our data collection functions to prevention strategies.

Research is essential for a public health organisation to move forward, allowing it to develop and apply its evidence pool and expertise. Every health improvement programme, every emergency response is a learning opportunity if we apply appropriate research methodologies with scientific rigour.

PHE also offers a rich learning and training environment, helping public health researchers to enjoy a rewarding career. PHE contributes significantly to training the next generation of researchers, with more than 70 PhD students from a wide range of institutions training at PHE.

These students gain insights into how research informs practice and policy, either in national or local public health programmes or in mitigation of the impacts of outbreaks, disasters and other emergencies globally.

The following case studies show examples from PHE’s wide range of activities. We are proud to be among the world’s most research-active health agencies.

Case study 1: evaluation of the shingles vaccination programme

Herpes zoster (shingles) is a painful, sometimes debilitating condition, the incidence of which increases with age. Postherpetic neuralgia, a painful condition that affects the nerve fibres and skin, is a complication of shingles. In 2013, a herpes zoster vaccination programme was introduced in England for adults aged 70 years with a phased catch-up programme for those aged 71 to 79 years.

An evaluation of the effect of the first 3 years of the vaccination programme on disease incidence in this population was undertaken by PHE, in collaboration with the Royal College of General Practitioners Research and Surveillance Centre and the University of Surrey.

Impact

Unlike many vaccination programmes in which the herd protection effects (when a large percentage of a population has become immune to an infection, thereby providing a measure of protection for individuals who are not immune) contribute to the overall population impact, any impact of the herpes zoster programme occurs through individual direct protection.

This, together with the phased implementation adopted in England, provided an opportunity to assess whether a discernible population impact had occurred. The results translate to about 17,000 fewer herpes zoster episodes and 3,300 fewer episodes of postherpetic neuralgia (pain in the nerves and skin) among the 5·5 million individuals targeted for vaccination in the first 3 years of the programme, whereas the incidence of herpes zoster in the general population increased over the same timeframe.

Despite the encouraging uptake levels early in the vaccination programme, coverage has declined by 6·9% since the start of the programme. The benefits of the programme need to be communicated to health professionals and the public to maximise protection in those most at risk from this potentially debilitating condition.

The findings indicate that the real-world impact of the herpes zoster vaccination programme is somewhat higher than estimated in clinical studies, consistent with the vaccine resulting in fewer patients with severe forms of disease presenting to healthcare services. These results suggest the initial cost-effectiveness of the UK programme might have been underestimated.

The impact of the programme should also be communicated to health professionals and the public in all countries where national recommendations exist to improve understanding of how vaccine uptake can maximise public health benefits.

Source of case study.

Case study 2: meningitis vaccine safety and immunogenicity

Invasive meningococcal disease is an important public health problem, especially in sub-Saharan Africa. After introduction of vaccination in 2010, Neisseria meningitidis serogroup A disease has been almost eliminated from the region.

However, serogroups C, W, Y, and X continue to cause disease outbreaks. A pentavalent meningococcal conjugate vaccine targeting serogroups A, C, Y, W, and X was assessed in a first-in-man, phase 1 study.

The large collaborative study group includes PHE.

The challenge

A single-centre, double-blind, randomised controlled trial was undertaken at a research clinic in Baltimore (USA). Participants were randomly assigned into groups for vaccination with adjuvant, vaccination without adjuvant or to the control group, who received the quadrivalent meningococcal conjugate vaccine.

After vaccination, participants were observed in the clinic for 60 minutes for adverse reactions. Participants recorded daily temperature and injection site or systemic reactions at home and returned to the clinic for follow-up visits on days 7, 28 and 84 for safety assessments; blood samples were also collected on day 7 for safety laboratory assessment.

A phone call contact was made 6 months after vaccination. Serum was collected before vaccination and 28 days after vaccination for immunological assessment.

Impact

The currently available licensed multivalent meningococcal conjugate vaccines do not provide protection against serogroup X meningococcal disease and are not affordable for wide-scale implementation in low-resource countries, such as those in the African meningitis belt.

The vaccine in this phase 1 trial was well tolerated and elicited serum antibodies that are predicted to confer protection against all 5 serogroups. Additional clinical trials are necessary to confirm the safety and immunogenicity of the vaccine in target populations.

Ultimately, the vaccine could be introduced into sub-Saharan Africa for further elimination of meningococcal disease. The vaccine could also be used in other countries where the disease is endemic, for travellers to sub-Saharan Africa and during Hajj or Umrah.

Source of case study.

Case study 3: new method for measuring incidence of new cases of HIV

Much of the work around the HIV epidemic in England focuses on predominantly black African people and men who have sex with men (MSM). New techniques for diagnosing HIV, as well as an increased number of black African and MSM attending clinics for testing has given rise to a higher incidence of HIV within this group (from observations).

For heterosexual black African males, however, the incidence of new HIV cases has dropped over the past 10 years. While this is encouraging, a more accurate method of measuring incidence of new cases of HIV in heterosexual black African males is needed.

This study was led by PHE with Imperial College London and Medical Research Council Biostatistics Unit, Cambridge.

The challenge

Current methods for measuring the incidence of HIV in MSM are not well adapted for heterosexuals, due to a lack of behavioural information from within the heterosexual population and inappropriate assumptions concerning migration. This is particularly important when measuring HIV in minority ethnic populations.

Many countries have turned to using biomarkers for recent HIV infections to estimate incidence; both timely and relatively low-cost, this approach could allow for better estimates within heterosexual populations.

The introduction of HIV testing in 1999, which subsequently developed into a national programme run by PHE, now sees nearly half of the UK population of black African men, women and MSM having had an HIV test, hence significant numbers of new infections are likely to be picked up in testing clinics.

Combining comprehensive testing data with biomarker data can help create a better estimation of HIV incidence, including in black African heterosexuals.

Impact

Heterosexual men and women of black African ethnicity is one of the largest sub-populations living with HIV in the UK. In this study, measures for HIV incidence in heterosexuals of black African ethnicity indicated an incidence rate around four-fold higher than other heterosexuals who attended sexual health clinics.

The methods used in this study provide improved precision when compared to other estimation methods, including effective estimation for at-risk groups.

The HIV incidence over 5 years showed that the black African population who attended sexual health clinics remain disproportionately at risk of infection in England, with an estimated 500 black African heterosexuals across the UK acquiring the infection each year during the 5 years of the study.

Following a reconfiguration of sexual health services in England in 2013, accurate information on incidence of HIV helps to better identify a need for services. Regular testing for HIV is still encouraged and should be promoted for those in high-risk groups.

Source of case study.

Case study 4: active tuberculosis case-finding among the homeless

Homeless people have an elevated risk of tuberculosis (TB) and are under-served by conventional health services. Approaches to active case-finding and treatment tailored to their needs are required.

There are several possible approaches to screening using different technologies in a mobile unit, including on-site chest X-rays, a rapid diagnostic test or both.

This study, by the NIHR Health Protection Research Unit in Modelling Methodology (a partnership between Imperial College, London and PHE) and University College London, evaluated different screening approaches using an integrated transmission-dynamic and health-economic mathematical model.

Impact

The model accounts for individual-level active case-finding benefits such as early TB detection and early treatment initiation and accounts for population-level benefits in reducing TB transmission.

The most efficient strategy for active case-finding was generally the rapid diagnostic test or X-ray in combination with the diagnostic test, depending upon the proportion of patients who are willing to wait the 90 minutes required for the test result. The willingness of patients to wait shows whether the most efficient approach is the single-step test or the test combined with X-ray.

The benefit of using the diagnostic test in the mobile unit is that it reduces the number of patients who are referred to hospital because only those with TB diagnosed by the test are referred for treatment, rather than all patients with abnormal X-ray being referred for diagnostic testing.

Active case-finding and enhanced case management of treated patients can reduce TB transmission among the homeless, by both reducing the period for which individuals are infectious prior to diagnosis and by promoting successful treatment. A reduction in transmission reduces TB incidence, thereby reducing future prevalence of disease and the need for care.

Source of case study.

Case study 5: trial of an ‘Alcohol Champions’ programme

PHE worked in collaboration with the universities of Salford, Bristol, York, and local authority Public Health teams to develop and evaluate an asset-based community development programme, Communities in Charge of Alcohol (CICA), which aims to reduce harm caused by alcohol.

The challenge

As a national and global health priority, tackling harm caused by alcohol could have a significant impact on people’s health and wellbeing, reduce the number of deaths and improve societal behaviours.

Excessive alcohol consumption can lead to a decline in physical health, as well as social health. The damage that alcohol can have on society and communities means that more initiatives to mitigate harm are needed. Though some brief interventions have been seen to be effective, this study looks at how local resources, including individuals, can be utilised.

Individuals recruited as ‘Alcohol Health Champions’ in their community, promoted and supported healthy relationships with alcohol, such that, at community level, steps were taken to reduce the availability of alcohol.

Impact

While asset-based community development approaches are recommended, they still somewhat lack evidence. As such, the evaluation of CICA should add to the body of evidence, increasing knowledge of the effectiveness of similar interventions.

The inclusion of randomisation, health economics and new methods for analysing natural experiments strengthens the usefulness of such evaluations.

Importantly, as ‘asset’ in the context of asset-based community development approaches refers to any factor that enhances the ability to create or sustain health and wellbeing, the findings of the evaluation are expected to be widely relevant to other topics, not just interventions about reducing alcohol harm.

Source of case study.

Case study 6: is there evidence that bioaerosol emissions from intensive farms pose health risks to nearby residents?

We live in a world with an increasing population count, and therefore, an increasing demand for food. To meet this demand, there is widespread use of intensive farming practices. This means a larger number of animals are kept (and therefore higher food output is achieved) per unit of land. These farms typically hold large numbers of animals, often indoors.

Biological air pollutants (often called bioaerosols) can be emitted in high concentrations from intensive farms. Bioaerosols are collections of airborne biological materials (for example, fungi and bacteria). Exposure to bioaerosols from farms has been linked to ill health, particularly respiratory illnesses.

This has led to concern about the potential health effects on communities living near intensive farms. However, some studies have shown that early exposure to bioaerosols might help build up resistance to respiratory diseases in adulthood. To establish and implement appropriate strategies and effective measures to mitigate risk, it is essential that regulatory authorities have access to accurate information and understanding.

Impact

By reviewing the most up-to-date scientific evidence, PHE, in collaboration with Imperial College London, found (based on a small number of studies) a modest but consistent association between proximity to an intensive farm and self-reported asthma among children. There were mixed results in adults, with some studies reporting adverse self-reported respiratory health effects and others reporting no effect or even a protective effect.

For children, the study designs meant it was difficult to draw conclusions about whether this was a causal association. While this review provides an analysis of the current evidence base, it also highlights important knowledge gaps and directions for further research. We hope that the information in this review will help in the development of regulatory risk assessments in relation to intensive farming.

Source of case study.

Case study 7: assessing exposure to a herbicide

Methods developed by PHE, in collaboration with Dow AgroSciences and Kings College London, originally for the assessment of radionuclide internal dosimetry were modified to develop physiologically based toxicokinetic (PBTK) models to assess internal exposure to the herbicide haloxyfop (which is used to control annual and perennial grass weeds in broadleaf crops).

Understanding internal concentrations is important for risk assessment; risk is the mathematical product of both hazard and exposure. Assessing exposure has always been challenging.

External exposure does not necessarily reflect the concentration at the (internal) site of toxicity because it is subject to organ-specific variables such as absorption, metabolism and excretion. Internal exposure cannot usually be measured directly and thus has to be calculated.

The target organ for haloxyfop is the liver. Physiologically based toxicokinetic modelling using Bayesian methods allows distributions to be assigned to take account of population variability and uncertainty in these calculations.

Impact

Modelling of data from crop-sprayer operators indicated that the major exposure route for haloxyfop was through the skin in all cases and that one operator had received a dose to the liver that was close to the acceptable operator exposure level. The reason for this higher than expected operator exposure is not known but assumed to be operator error in use or failure to use appropriate personal protection equipment.

The estimates of operator exposure to haloxyfop obtained through the modelling can be compared with other estimates of exposure available in the literature; the aim of this study was to create a statistical model which could utilise data from a range of sources. Furthermore, the estimates of exposure may be useful for informing chemical risk management and stewardship of commercial products containing haloxyfop.

Source of case study.

Case study 8: implications from the inhalation of nanoparticles

Previous observations of exposure to cerium dioxide nanoparticles, which are used in fuel production and precision polishing, had been seen to have a negative impact on healthy animals, but there is little evidence of its effect on lung conditions such asthma and chronic obstructive pulmonary disease (COPD). Cerium dioxide nanoparticles were seen to exacerbate responses to house dust mite allergen exposure and to increase inflammation of the lungs.

The challenge

Cerium dioxide nanoparticles have many practical uses and even have some therapeutic applications as an oxidisation reducer when used carefully and in a controlled environment. However, inhalation of these small particles, either accidentally or as part of someone’s job, could be toxic and cause serious effects on the health of our lungs.

With a lack of information on how exposure to these particles might affect the health of people with asthma or COPD, this study, involving the NIHR Health Protection Research Unit (HPRU) for Health Impact of Environmental Hazards at King’s College London in partnership with PHE, set out to look at their effects using house dust mite allergen exposure.

Impact

While exposure to the nanoparticles alone did not significantly affect the lungs of healthy animals, those exposed to house dust mite allergens in combination with nanoparticles showed altered pulmonary inflammatory responses. The molecular and cellular profile of those responses was similar to what is seen in asthma. The data from this study helps to understand the potential implications of work-related and accidental inhalation of nanoparticles for those susceptible to respiratory disease.

Source of case study.

Case study 9: expansion of the Antibiotic Guardian behavioural campaign across Europe

Antimicrobial resistance (AMR) is recognised as a major public health threat. Improving awareness and understanding of antimicrobial resistance is one of the 5 strategic objectives of the World Health Organization (WHO) Global AMR action plan.

In 2014, PHE developed the behaviour change and engagement campaign, Antibiotic Guardian to tackle antimicrobial resistance in the UK. This included an online pledge system aimed at healthcare professionals, healthcare authorities and the public.

Evaluation of the campaign found increased knowledge and changes in behaviour (self-reported), regarding antimicrobial resistance. Due to the impact, the WHO-Europe and the Belgian Antibiotic Policy Coordination Committee (BAPCOC) entered into collaboration with PHE to translate the Antibiotic Guardian campaign into Russian, Dutch and French and assess the campaign’s initial uptake and impact.

Impact

Initial results after 2 months showed a significant increase in the proportion of pledges from European countries (excluding the UK). Knowledge of antimicrobial resistance was greater in those who had made the Antibiotic Guardian pledge (including the public group) compared to participants in other surveys.

This is encouraging and could be an indicator of the knowledge acquired through the campaign but may also reflect a bias in the campaign towards those already engaged in combatting antimicrobial resistance. Knowledge prior to becoming an Antibiotic Guardian was not measured. There was a variation in engagement, type of people making a pledge and how they heard about the campaign across the 3 languages.

The pages in Dutch received the highest proportion of pledges from the public. Little is known on the impact of promotional activities within countries to understand these differences.

Greater promotion of the Antibiotic Guardian campaign is required across Europe to increase the number of pledges and enable clear assessment of its impact on tackling antimicrobial resistance.

Both WHO and BAPCOC confirmed future promotional plans, including asking all health insurance companies in Belgium to invite members to become an Antibiotic Guardian.

Source of case study.

Case study 10: new drug resistance identified in an HIV patient

The effectiveness of drugs used to treat HIV infection may be compromised if patients have mutations in target molecules. A case of confirmed transmission of R263K integrase mutation was reported by a collaboration between University Hospitals Bristol NHS Foundation Trust, Great Western Hospitals NHS Foundation Trust (Swindon) and PHE.

This appears to be the first description of sexual transmission of R263K and M184V mutations. The case was also unique as it involves a previously HIV negative patient (such as a drug-naive) who, on testing HIV positive, failed to respond to treatment with Triumeq due to 3 resistance mutations.

Impact

Previous studies have suggested that it is rare for the R263K mutation to develop in the presence of nucleoside reverse transcriptase inhibitor mutations such as M184V. This case illustrates that this is not only possible but can also pose a transmission risk.

With the increasing use of integrase inhibitor drugs, it is likely that other cases of resistance will be recorded. It is important to consider baseline integrase resistance testing in patients to ensure a robust treatment regimen is chosen and to avoid placing them at risk of developing further resistance that could jeopardise treatment options for the future.

Source of case study.

Case study 11: effectiveness of biocides

The rapid acquisition within bacteria of new drug-resistance mechanisms and the lack of novel antibiotics in development mean increased reliance on infection prevention, including disinfectant usage to prevent hospital outbreaks of multi-drug resistant bacteria. Cationic disinfectants, such as chlorhexidine, are widely used in clinical settings, for example, for wound dressings and skin cleaning prior to surgical procedures, as well as being present in products such as mouthwashes.

They generally have both bacteriostatic (inhibits bacterial growth) and bactericidal (kills bacteria) mechanisms of action that are concentration-dependent. Testing of the susceptibility of bacteria to cationic antibiotics, particularly colistin, is often problematic with variability in results. This study, by PHE, aimed to understand the importance of laboratory factors in the reliable testing of bacterial susceptibility to cationic disinfectants.

Impact

Results showed that minimum inhibitory and bactericidal concentrations values of some disinfectants differed significantly according to the material of the containers in which the bacteria were grown (lower on polypropylene plates when compared to polystyrene plates). These values were also different for some bacterial strains. Alterations to biocide efficacy due to the composition of the media in which the bacteria were grown appeared to be organism-dependent.

There is an increasing number of reports of bacterial strains that are multi-drug resistant; the use of biocides as part of infection control is crucial in helping to limit their spread. Unlike for antibiotics, there are few standardised measuring techniques to understand an organism’s resistance to biocides.

This study demonstrates the impact of media composition and plate material on variation and reporting of the susceptibility of several bacterial species to specific cationic biocides. It highlights the need to standardise biocide susceptibility testing.

Source of case study.

Case study 12: understanding Legionella pneumophila populations

The diversity of Legionella pneumophila populations within single water systems is not well understood, particularly in water systems not associated with cases of Legionnaires’ disease. In a collaborative study between the Wellcome Sanger Institute and PHE, genomic analysis of 235 L. pneumophila isolates obtained from 28 water samples in 13 locations within a single, large occupational building was undertaken.

Despite regular treatment, the water system of this building is thought to have been colonised for at least 30 years without evidence of association with Legionnaires’ disease cases.

Impact

The study found co-existence of 3 highly clonal populations of isolates belonging to 3 sequence types. All 3 sequence types have previously been recovered from Legionnaires’ disease patients, suggesting that the building isolates have pathogenic capacity despite never having been linked to disease cases.

It is possible that the genetic composition of strains may not be the crucial factor contributing to outbreaks, but rather that other local factors, including the method of exposure, the L. pneumophila concentration and/or the immune status of the exposed individuals, are also important.

Evidence for spatial structuring of the L. pneumophila population within the water system was found. The 3 sequence types were never found all together, neither in a single sample, nor from different samples collected from the same location. While this may be the result of a sampling artefact, it was considered plausible that co-existence of all 3 sequence types in the same location is ecologically improbable due to competition dynamics.

The findings demonstrate that while a single sample will usually provide representation of the different types present in the immediate vicinity, it will likely fail to capture the full spectrum of strain differences, reinforcing the need for deep sampling and high-resolution analysis during environmental investigations.

Source of case study.

Case study 13: complete genome sequence of Buffalopox virus

Buffalopox virus is related to other viruses such as monkeypox, horsepox, variola and cowpox. Buffalopox virus can cause mild to severe diseases in buffaloes and cattle and is highly transmissible to people. The disease has persisted in the Indian subcontinent for more than 30 years following the end of human vaccination against smallpox virus.

Although it is not regularly transmitted between people, there have been cases in immunocompromised individuals. A deeper understanding of the viral genome, as presented here by PHE authors, will contribute to improvements in surveillance and disease control.

Impact

The Buffalopox genome presents an average G+C content of 33.4% and contains at least 177 protein-coding genes. Whole-genome phylogenetic characterisation indicates that the parental strain of modified vaccinia virus Ankara is the closest relative to Buffalopox.

The annotated genome sequence is deposited in GenBank under the accession number MG599038. Buffalopox virus is publicly available from the National Collection of Pathogenic Viruses (NCPV), a collection held by PHE.

Source of case study. 

Case study 14: mental health screening for people affected by the 2015 to 2016 terrorist attacks in Tunisia, Paris and Brussels

Following several terrorist attacks in 2015 and 2016, a national programme was set up to identify and support residents of England whose mental health had been affected. The outcomes of the programme’s screening and assessment components are reported by a collaboration between King’s College London, South London and Maudsley NHS Foundation Trust, Sussex Partnership NHS Foundation Trust, University of Sussex and PHE.

Impact

The implementation of this programme marks only the second time a bespoke centralised intervention has been developed in England to support the early identification and treatment of psychological disorders following a terrorist attack. Ultimately 78 adults (40.4% of all adults who returned a questionnaire or self-referred) and 3 children (42.9%) were referred to local mental health services for evidence-based treatments.

The study results showed that more people had accessed counselling via their tour operator than via their GP and although most respondents reported receiving some form of intervention, whether this intervention was in line with NICE recommendations remained uncertain. Further discussion about how to integrate tour operators and NHS provisions for future incidents that occur overseas may be worthwhile.

One of the main issues encountered by the programme was the reliability and accessibility of contact information for those involved. Records from tour operators were unavailable due to data protection issues. The response rate for the screening questionnaire was poor, estimated at 30%.

The results suggest that a screening programme can produce substantial benefits by identifying people who have been affected and supporting them in accessing treatment, but it is likely that some people who may have benefited from the programme were not contacted and remained unaware of its existence. Similar screening programmes to that which is reported here are in development and further efforts will be required to ensure access to services as future incidents occur.

Source of case study.

Case study 15: progress of the Healthier You programme

The prevalence of diabetes in England has increased by 75% from 2.3 million in 2009 to 2010 to 3.0 million in 2015 to 2016. Trials have shown that onset of type 2 diabetes can be prevented or delayed through behavioural interventions.

The Healthier You: NHS Diabetes Prevention Programme was developed to prevent or delay onset of type 2 diabetes in adults already identified to be at high risk. Individuals identified are offered a place on a behavioural intervention. Four service providers were appointed, each with the ability to provide the behavioural interventions in localities across England. The behavioural interventions enable weight loss, increased physical activity and improved nutrition through face‐to‐face group‐based sessions.

A clinical and cost‐effectiveness evaluation of the programme has been commissioned by the NIHR and will report in 2021. The purpose of this paper, a collaboration between PHE, Diabetes UK and NHS England, is to describe early progress of the Healthier You programme.

Impact

There was variation in referral rates to Healthier You across local health economies. The analyses show that referral numbers and percentage uptake are in excess of prior modelled values.

Characteristics of attendees suggest that the programme is reaching those who are both at greater risk of developing type 2 diabetes and who typically access healthcare less effectively, although efforts at engaging those most deprived have not been as successful for white European groups as for other ethnic groups. This report provides a platform for ongoing learning and improvements.

Source of case study.

Case study 16: is there a relationship between oral health and dementia?

This review aimed to explore the most contemporary evidence on whether poor oral health and dementia occurs in the same individuals or populations, to outline the nature of the relationship between these 2 health outcomes and to discuss the implication of any findings for health services and future research.

The review was undertaken by a working group comprising Trinity College Dublin, King’s College London, King’s College Hospital NHS Foundation Trust, the University of Portsmouth and PHE.

Impact

This rapid review highlights the paucity of evidence on the relationship between dementia and oral health over the 10-year review period. The evidence available is of mixed quality and covers a wide range of oral diseases and conditions.

Risk factors and risk predictors for dementia are of interest in current research, particularly the early detection and identification of disease. There is very weak and limited evidence that in the absence of regular toothbrushing, the presence of gingivitis and reduced masticatory function may be risk factors for dementia, but there is no evidence of a direct effect on caries and periodontal disease.

There is, however, sufficient emerging evidence to suggest that this is an important area for further research given demographic changes and the fact that older adults have already experienced significant oral disease and its sequelae. It is important to explore the possible value of multidisciplinary research approaches.

For example, there is potential for collaboration with physiotherapists and occupational therapists to focus on the activities of daily living concurrently such as manual dexterity, gait and toothbrushing. Dieticians with their expertise in nutrition could ensure diet plans consider oral health and speech and language therapists could contribute with their assessment of concomitant swallowing difficulties, as these are prevalent in people with dementia and may affect oral hygiene practices and oral microflora.

This approach will also help to explore the holistic relationships of dementia, oral health and general health.

Source of case study.

Case study 17: evaluation of a lifestyle weight management service

Adult obesity in the UK remains a public health priority. Current guidance recommends that local areas provide multicomponent interventions to treat overweight and obese adults. However, there is currently a dearth of published evidence on the evaluation of these programmes. This study, a collaboration between Teesside University, North Yorkshire County Council, Durham University, Newcastle University and PHE, reports on a mixed-method evaluation of 7 weight management programmes funded by a local authority in the North of England.

Impact

This study demonstrates that real-world weight management services can achieve results that are comparable to research trial evidence, although success varies depending on the delivery model used. In addition, evidence for impact is limited due to a lack of long term service provision and data collection.

It also confirms that inequalities exist in the use of local services by lower socio-economic status groups; men, younger adults and black and minority ethnic communities. Useful learning points for improvements in real-world weight management services are proposed: a requirement for standardised data collection and management tools, staff training and communication strategies.

The programmes should also be tailored to local needs and joined with national support services; programmes should offer ongoing peer support, continuous monitoring and feedback along with physical activities tailored to user needs.

Source of case study.

Case study 18: use of whole-genome sequencing to investigate food poisoning cases

Yersinia enterocolitica is a Gram-negative bacterium widely found in different animals and environmental settings. Infection with Y. enterocolitica can cause a feverish, diarrhoeal illness and acute abdominal pain. The majority of Y. enterocolitica cases are caused by the consumption of pork and porcine products, although outbreaks have also been associated with other foods such as salad and pasteurised milk.

In 2015, Y. enterocolitica was the third most commonly reported zoonosis (a disease which can be transmitted to humans from animals) in the EU. This study involving the NIHR Health Protection Research Unit (HPRU) in Gastrointestinal Infections (a partnership between the University of Liverpool and PHE) and the Royal Liverpool and Broadgreen University Hospitals NHS Trust investigated a cluster of cases in Liverpool.

Impact

This paper is the first documented use of whole-genome sequencing to investigate a cluster of Y. enterocolitica cases. In this cluster investigation of the whole-genome sequencing results indicated that the cases were genetically distinct. While it is possible that in certain circumstances different sequence types may be isolated from the same source, the genetic distances between samples allowed the investigation team to conclude that the cases were not from a common source.

This indicated to the Outbreak Control Team that further investigation was not necessary and the investigation was closed. The whole-genome sequencing results, therefore, had a direct impact on public health action and resource allocation. The use of whole-genome sequencing linked to detailed epidemiological data would greatly enhance public health surveillance of this clinically significant foodborne pathogen.

Source of case study.

Case study 19: aiming to reduce cancer through behaviour modification

The objective of cancer risk-reduction policies is to reduce levels of cancer incidence. Such policies are based on evidence about risk factors and whether it is possible to reduce exposure to risk factors through behaviour modification, particularly at a population level.

A team led by Cancer Research UK looked at data from cancer registration services across the UK, including the National Cancer Registration and Analysis Service within PHE, on the number of risk factor-attributable cancers recorded.

The challenge

Over the past decade cancer incidence in the UK has increased, with a slower rate of increase projected over the next 20 years, largely due to the fall in numbers of people smoking. Changes in exposure to risk factors are important drivers of changes in cancer incidence, with improvements in cancer diagnosis and data capture contributing to a lesser extent.

The prevalence of risk factor exposure varies across the constituent countries within the UK and this study builds on previously published methodology to update population attributable fractions for specific cancer types and risk factors, as well as for all cancers and risk factors combined.

Impact

Known risk factors are responsible for a substantial proportion of UK cancer cases. Prevention efforts that focus on smoking and overweight and obesity are likely to have the largest population-level impact. Between-country variation likely reflects population demographics and deprived communities across the UK may require additional support to reduce risk.

This study provides evidence to focus efforts on reducing the number and proportions of cancers attributable to preventable risk factors across the countries of the UK.

Source of case study.

Reflection: Impact through training. From Jonathan Abrahams, PhD student

Whooping cough is commonly thought of as a ‘disease of the past’, but the incidence of disease in the UK has risen over the last decade and there was a major outbreak in 2012. The bacterium Bordetella pertussis is the causative agent of whooping cough, and despite being an important pathogen, little is known about the genes that allow B. pertussis to cause this deadly disease. I am undertaking a PhD at the University of Bath, part-funded by PHE, to investigate mechanisms of genetic variation involved in B. pertussis evolution.

Through the guidance of my supervisor at PHE, Professor Andrew Gorringe, I was able to develop this topic and draw on his knowledge and contacts. The close collaboration between PHE and other national public health agencies, in particular the (American) Centers for Disease Control and Prevention (CDC), built the foundation of my studies.

Both PHE and CDC contributed strains from recent outbreaks, advanced sequencing data and main insights. Through these discussions and collaborations with both PHE and CDC the topic of my PhD evolved: Exploring novel genetic mutations in B. pertussis.

In contrast to many other bacterial pathogens, B. pertussis isolates from around the world are very similar; there appears to be very limited genetic diversity in this species. Our knowledge, however, was limited by the technology used to analyse these strains. At the beginning of my PhD in 2016, new `long read’ sequencing technologies were maturing.

Leveraging the power of these new sequencing platforms through my connection to PHE, we have demonstrated previously hidden mutations and duplications, some of which involve hundreds of genes. My studies have greatly revised the picture of genetic diversity among B. pertussis. I have presented my work to diverse audiences at the PHE PhD student conference and in a seminar at PHE Porton, which were invaluable experiences.

As I finish my PhD studies, I am looking forward to fostering the close relationships I have made with members of staff at PHE and continuing, with their assistance, to unravel the mysterious genetics of Bordetella pertussis.