Sam Ghebrehewet

Effect of socioeconomic deprivation on uptake of measles, mumps and rubella vaccination in Liverpool, UK over 16 years: a longitudinal ecological study

Suboptimal uptake of the measles, mumps and rubella (MMR) vaccine by certain socioeconomic groups may have contributed to recent large measles outbreaks in the UK. We investigated whether socioeconomic deprivation was associated with MMR vaccine uptake over 16 years. Using immunization data for 72,351 children born between 1995 and 2012 in Liverpool, UK, we examined trends in vaccination uptake. Generalized linear models were constructed to examine the relative effect of socioeconomic deprivation and year of birth on MMR uptake. Uptake of MMR1 by age 24 months ranged between 82·5% in 2003 [95% confidence interval (CI) 81·2-83·7] and 93·4% in 2012 (95% CI 92·7-94·2). Uptake of MMR2 by age 60 months ranged between 65·3% (95% CI 64·4-67·4) in 2006 and 90·3% (95% CI 89·4-91·2) in 2012. In analysis adjusted for year of birth and sex, children in the most deprived communities were at significantly greater risk of not receiving MMR1 [risk ratio (RR) 1·70, 95% CI 1·45-1·99] and MMR2 (RR 1·36, 95% CI 1·22-1·52). Higher unemployment and lower household income were significantly associated with low uptake. Contrary to concerns about lower MMR uptake in affluent families, over 16 years, children from the most socioeconomically deprived communities have consistently had the lowest MMR uptake. Targeted catch-up campaigns and strategies to improve routine immunization uptake in deprived areas are needed to minimize the risk of future measles outbreaks.

The economic cost of measles: Healthcare, public health and societal costs of the 2012–13 outbreak in Merseyside, UK

BACKGROUND Measles is a highly contagious vaccine-preventable infection that caused large outbreaks in England in 2012 and 2013 in areas which failed to achieve herd protection levels (95%) consistently. We sought to quantify the economic costs associated with the 2012-13 Merseyside measles outbreak, relative to the cost of extending preventative vaccination to secure herd protection. METHODS A costing model based on a critical literature review was developed. A workshop and interviews were held with key stakeholders in the Merseyside outbreak to understand the pathway of a measles case and then quantify healthcare activity and costs for the main NHS providers and public health team incurred during the initial four month period to May 2012. These data were used to model the total costs of the full outbreak to August 2013, comprising those to healthcare providers for patient treatment, public health and societal productivity losses. The modelled total cost of the full outbreak was compared to the cost of extending the preventative vaccination programme to achieve herd protection. FINDINGS The Merseyside outbreak included 2458 reported cases. The estimated cost of the outbreak was £ 4.4m (sensitivity analysis £ 3.9 m to £ 5.2m) comprising 15% (£ 0.7 m) NHS patient treatment costs, 40% (£ 1.8m) public health costs and 44% (£ 2.0m) for societal productivity losses. In comparison, over the previous five years in Cheshire and Merseyside a further 11,793 MMR vaccinations would have been needed to achieve herd protection at an estimated cost of £ 182,909 (4% of the total cost of the measles outbreak). INTERPRETATION Failure to consistently reach MMR uptake levels of 95% across all localities and sectors (achieve herd protection) risks comparatively higher economic costs associated with the containment (including healthcare costs) and implementation of effective public health management of outbreaks. FUNDING Commissioned by the Cheshire and Merseyside Public Health England Centre.

Influenza vaccination for healthcare workers in the UK: appraisal of systematic reviews and policy options

Background The UK Department of Health recommends annual influenza vaccination for healthcare workers, but uptake remains low. For staff, there is uncertainty about the rationale for vaccination and evidence underpinning the recommendation. Objectives To clarify the rationale, and evidence base, for influenza vaccination of healthcare workers from the occupational health, employer and patient safety perspectives. Design Systematic appraisal of published systematic reviews. Results The quality of the 11 included reviews was variable; some included exactly the same trials but made conflicting recommendations. 3 reviews assessed vaccine effects in healthcare workers and found 1 trial reporting a vaccine efficacy (VE) of 88%. 6 reviews assessed vaccine effects in healthy adults, and VE was consistent with a median of 62% (95% CI 56 to 67). 2 reviews assessed effects on working days lost in healthcare workers (3 trials), and 3 reported effects in healthy adults (4 trials). The meta-analyses presented by the most recent reviews do not reach standard levels of statistical significance, but may be misleading as individual trials suggest benefit with wide variation in size of effect. The 2013 Cochrane review reported absolute effects close to 0 for laboratory-confirmed influenza, and hospitalisation for patients, but excluded data on clinically suspected influenza and all-cause mortality, which had shown potentially important effects in previous editions. A more recent systematic review reports these effects as a 42% reduction in clinically suspected influenza (95% CI 27 to 54) and a 29% reduction in all-cause mortality (95% CI 15 to 41). Conclusions The evidence for employer and patient safety benefits of influenza vaccination is not straightforward and has been interpreted differently by different systematic review authors. Future uptake of influenza vaccination among healthcare workers may benefit from a fully transparent guideline process by a panel representing all relevant stakeholders, which clearly communicates the underlying rationale, evidence base and judgements made.

Reasons for measles cases not being vaccinated with MMR: investigation into parents' and carers' views following a large measles outbreak

Uptake rates for the combined measles, mumps and rubella (MMR) vaccine have been below the required 95% in the UK since a retracted and discredited article linking the MMR vaccine with autism and inflammatory bowel disease was released in 1998. This study undertook semi-structured telephone interviews among parents or carers of 47 unvaccinated measles cases who were aged between 13 months and 9 years, during a large measles outbreak in Merseyside. Results showed that concerns over the specific links with autism remain an important cause of refusal to vaccinate, with over half of respondents stating this as a reason. A quarter stated child illness during scheduled vaccination time, while other reasons included general safety concerns and access issues. Over half of respondents felt that more information or a discussion with a health professional would help the decision-making process, while a third stated improved access. There was clear support for vaccination among respondents when asked about current opinions regarding MMR vaccine. The findings support the hypothesis that safety concerns remain a major barrier to MMR vaccination, and also support previous evidence that experience of measles is an important determinant in the decision to vaccinate.

Some factors affecting rubella seronegative prevalence among pregnant women in a North West England region between April 2011 and March 2013

BACKGROUND Rubella is usually a mild viral illness, but during pregnancy, it can have potentially devastating effects causing fetal losses and severe congenital malformations (congenital rubella syndrome). Rubella is now rare in most developed countries following a successful vaccination programme. We aimed to investigate differences in epidemiological profile of pregnant women screened antenatally in Liverpool to identify risk factors for rubella immunity. METHODS All samples were tested with the Elecsys Rubella IgG immunoassay kit. A result <10 IU/ml was considered to be seronegative. RESULTS The seronegativity prevalence among pregnant women in Liverpool (6.3%) is higher than average value for the North West region (3.7%). The seronegative rates varied with age (15.4% for <15 years, 18.7% for 15-20 years, compared with 2% for 30-35 years). The areas with the highest seronegative rates correspond with areas of Liverpool with high pockets of socioeconomic deprivation. CONCLUSION The highest proportion of seronegative women were among the youngest age groups. Local areas with highest level of deprivation should be given priority and additional resources to develop targeted programmes and pathways to implement appropriate interventions such as MMR catch-up programmes and put in place arrangements for offering MMR vaccination in maternity units.

An Outbreak of Pseudomonas Aeruginosa Infection Linked to a “Black Friday” Piercing Event

Introduction Outbreaks linked to cosmetic piercing are rare, but can cause significant illness. We report the investigation and management of a point-source outbreak that occurred during a Black Friday promotional event in North West England. Methods Outbreak investigation was led by Public Health England, and included active case finding among individuals pierced at a piercing premises between 25/11/2016 (Black Friday) and 7/12/2016. Detailed epidemiological, environmental (including inspection and sampling), and microbiological investigation was undertaken. Results During the Black Friday event (25/11/2016), 45 people were pierced (13 by a newly-appointed practitioner). Eleven cases were identified (7 microbiologically-confirmed, 2 probable, and 2 possible). All cases had clinical signs of infection around piercing sites, and five required surgical intervention, with varying degrees of post-operative disfigurement. All confirmed and probable cases had a scaffold piercing placed with a guide bar by the newly-appointed practitioner. Pseudomonas aeruginosa, indistinguishable at nine-locus variable-number tandem repeat loci, was isolated from four of the confirmed cases, and from pre- and post-flush samples from five separate water taps (three sinks) in the premises. Water samples taken after remedial plumbing work confirmed elimination of Pseudomonas contamination. Discussion Although high levels of Pseudomonas water contamination and some poor infection control procedures were identified, infection appeared to require additional exposure to an inexperienced practitioner, and the more invasive scaffold piercing. A proactive collaborative approach between piercers and health and environmental officials is required to reduce outbreak risk, particularly when unusually large events are planned

Measles outbreaks in the UK, is it when and where, rather than if? A database cohort study of childhood population susceptibility in Liverpool, UK

Objectives There was a large outbreak of measles in Liverpool, UK, in 2012–2013, despite measles, mumps and rubella (MMR) immunisation uptake rates that were higher than the national average. We estimated measles susceptibility of a cohort of children born in Liverpool between 1995 and 2012 to understand whether there was a change in susceptibility before and after the outbreak and to inform vaccination strategy. Design Retrospective cohort study. Setting The city of Liverpool, North West UK. Participants All children born in Liverpool (72 101) between 1995 and 2012 inclusive who were identified using the Child Health Information System (CHIS) and were still resident within Liverpool in 2014. Primary and secondary outcome measures We estimated cohort age-disaggregated and neighbourhood-disaggregated measles susceptibility according to WHO thresholds before and after the outbreak for children aged 1–17 years. Results Susceptibility to measles was above WHO elimination thresholds before and after the measles outbreak in the 10+ age group. The proportion of children susceptible before and after outbreak, respectively: age 1–4 years 15.0% before and 14.9% after; age 5–9 years 9.9% before and 7.7% after; age 10+ years 8.6% before and 8.5% after. Despite an intensive MMR immunisation catch-up campaign after the 2012–2013 measles outbreak, the overall proportion of children with no MMR remains high at 6.1% (4390/72 351). Across all age groups and before and after the outbreak, measles susceptibility was clustered by neighbourhood, with deprived areas having the greatest proportion of susceptible children. Conclusions The risk of sustained measles outbreaks remains, especially as large pools of susceptible older children will start leaving secondary education and continue to aggregate in higher education, employment and other community settings and institutions resulting in the potential for a propagated measles outbreak.