Vaccination strategies for control of community outbreaks of hepatitis A: A comparison of two outbreaks in England.

In August 2015 two community outbreaks of hepatitis A virus (HAV) occurred in sub-urban communities in Northern England. Each was managed by an independent outbreak control team. In outbreak one, mass vaccination was deployed targeting a residential area and two schools, while in outbreak two, vaccination was reserved for household-type contacts of cases. The highest vaccination uptake was achieved in the school settings (82% and 95%). These case studies illustrate the range of approaches that can be used and the factors that influence decision-making in response to a hepatitis A community outbreak. Both outbreaks likely started from importation(s) of HAV by returning travellers and spread through extended social networks and the local community. Vaccination strategies were selected based on hypotheses about transmission pathways, which were informed by evidence from oral fluid (OF) testing of asymptomatic contacts. More evidence about the effectiveness of mass vaccination in community outbreaks of hepatitis A in low endemicity settings is needed. Hepatitis A guidelines should include recommendations for the use of mass vaccination and OF testing in outbreaks.

Should we be moving to a national standardized non-gadolinium MR imaging protocol for the surveillance of vestibular schwannomas?

OBJECTIVES:: To examine whether the model of Getting It Right First Time (GIRFT) could be relevant to the surveillance of non-operated vestibular schwannomas (vs) by testing the following hypotheses: (1) in the UK there is a great variation in the imaging protocol for the follow-up of vs; (2) high-resolution, T 2 weighted MRI (HRT 2W-MRI) has an equivalent accuracy to gadolinium-enhanced T 1 weighted MRI (Gd-MRI) in the assessment of vs size and; (3) imaging with HRT 2W-MRI rather than Gd-MRI could offer financial savings. METHODS:: Two neuroradiologists independently performed measurements of 50 vs imaged with HRT 2W-MRI and Gd-MRI. Differences in mean tumour measurements between HRT 2W-MRI and Gd-MRI were determined, as were intra- and interobserver concordance. Level of agreement was measured using Bland-Altman plots. Consultant neuroradiologists within 30 adult neurosurgical units in the UK were contacted via email and asked to provide the MRI protocol used for the surveillance of non-operated vs in their institution. The financial difference between scanning with HRT 2W-MRI and Gd-MRI was determined within Leeds Teaching Hospitals NHS Trust. RESULTS:: There was no statistically significant difference in the mean diameter of vs size, measured on HRT 2W-MRI and Gd-MRI (p = 0.28 & p = 0.74 for observers 1 and 2 respectively). Inter- and intraobserver concordance were excellent (Interclass correlation coefficient = 0.99, Interclass correlation coefficient ≥ 0.98 respectively). Differences between the two sequences were within limits of agreement. 26 of 30 UK neuroscience centres (87 % response rate) provided imaging protocols. 16 of the 26 (62%) centres use Gd-MRI for the surveillance of vs. HRT 2-MRI is £36.91 cheaper per patient than Gd-MRI. CONCLUSION:: Variation exits across UK centres in the imaging surveillance of non-operated vs. HRT 2W-MRI and Gd-MRI have equivalent accuracy when measuring vs. Imaging with HRT 2W-MRI rather than Gd-MRI offers potential financial savings. ADVANCES IN KNOWLEDGE:: This study highlights the potential health and economic benefits of a national standardized imaging protocol for the surveillance of non-operated vs.

Long-term physical activity: an exogenous risk factor for sporadic amyotrophic lateral sclerosis?

OBJECTIVES: To conduct a geographically defined, UK-based case-control study, to examine any association between physical activity (PA) and amyotrophic lateral sclerosis (ALS). METHODS: A novel historical PA questionnaire was designed, validated, and subsequently administered in individual face-to-face interviews of 175 newly diagnosed sporadic ALS cases and 317 age- and sex-matched community controls. Historical PA energy expenditure and time spent in vigorous-intensity PA were derived from questionnaire data and compared between cases and controls. RESULTS: Participation in an extra 10kJ/kg/day of PA (equivalent to approximately 45minutes brisk walking) was consistently associated with an increased risk of ALS, with the strongest association observed for adulthood exercise-related PA (OR 1.47, 95% CI 1.10-1.97). An extra 10mins/day of vigorous PA was also associated with the odds of ALS (OR 1.03, 95% CI 1·01-1·05). Results were slightly attenuated following adjustment for smoking and educational attainment. CONCLUSIONS: To our knowledge this is the first study to demonstrate a positive association between ALS and PA participation using a specifically designed and validated historical PA questionnaire. Despite the well-established health benefits of PA, a high activity lifestyle may also be associated with elevated risk of ALS. Large-scale prospective studies in the future may help to confirm this association.

Validation of the historical adulthood physical activity questionnaire (HAPAQ) against objective measurements of physical activity.

BACKGROUND: Lifetime physical activity energy expenditure (PAEE) is an important determinant of risk for many chronic diseases but remains challenging to measure. Previously reported historical physical activity (PA) questionnaires appear to be reliable, but their validity is less well established. METHODS: We sought to design and validate an historical adulthood PA questionnaire (HAPAQ) against objective PA measurements from the same individuals. We recruited from a population-based cohort in Cambridgeshire, UK, (Medical Research Council Ely Study) in whom PA measurements, using individually calibrated heart rate monitoring, had been obtained in the past, once between 1994 and 1996 and once between 2000 and 2002. 100 individuals from this cohort attended for interview. Historical PA within the domains of home, work, transport, sport and exercise was recalled using the questionnaire by asking closed questions repeated for several discrete time periods from the age of 20 years old to their current age. The average PAEE from the 2 periods of objective measurements was compared to the self-reported data from the corresponding time periods in the questionnaire. RESULTS: Significant correlations were observed between HAPAQ-derived and objectively measured total PAEE for both time periods (Spearman r = 0.44; P < 0.001). Similarly, self-reported time spent in vigorous PA was significantly correlated with objective measurements of vigorous PA (Spearman r = 0.40; P < 0.001). CONCLUSIONS: HAPAQ demonstrates convergent validity for total PAEE and vigorous PA. This instrument will be useful for ranking individuals according to their past PA in studies of chronic disease aetiology, where activity may be an important underlying factor contributing to disease pathogenesis.

Physical activity as an exogenous risk factor in motor neuron disease (MND): a review of the evidence.

Motor neuron disease (MND) is a devastating neurodegenerative condition associated with considerable disability and a poor prognosis. Despite improvements in symptomatic management in recent years, few therapies are available which modify survival. However, the challenge to find successful treatments would be greatly assisted by clearer elucidation of the underlying pathoaetiology. Many potential exogenous risk factors have been proposed as part of a gene-environment interaction in the aetiology of MND. A growing interest in the role of vigorous physical activity in the development of MND has followed reports of a higher than expected incidence of the disease in professional sports people. Such an association is also supported by current hypotheses concerning the cellular and genetic mechanisms of MND. However, evidence from epidemiological research remains conflicting and inconclusive. This article reviews the existing literature regarding physical activity as a risk factor for MND and the potential biological and genetic plausibility for this association.