HIGH SENSITIVE PCR METHOD FOR DETECTION OF PATHOGENIC Leptospira spp. IN PARAFFIN-EMBEDDED TISSUES

This study describes the development and application of a new PCR assay for the specific detection of pathogenic leptospires and its comparison with a previously reported PCR protocol. New primers were designed for PCR optimization and evaluation in artificially-infected paraffin-embedded tissues. PCR was then applied to post-mortem, paraffin-embedded samples, followed by amplicon sequencing. The PCR was more efficient than the reported protocol, allowing the amplification of expected DNA fragment from the artificially infected samples and from 44% of the post-mortem samples. The sequences of PCR amplicons from different patients showed >99% homology with pathogenic leptospires DNA sequences. The applicability of a highly sensitive and specific tool to screen histological specimens for the detection of pathogenic Leptospira spp. would facilitate a better assessment of the prevalence and epidemiology of leptospirosis, which constitutes a health problem in many countries.     

Exploring the broader health and well-being outcomes of mining communities in low- and middle-income countries: A systematic review

Health and well-being outcomes in communities living in proximity to mining activity may be influenced by a broad spectrum of factors including population growth, economic instability or land degradation. This review aims to synthesise broader outcomes associated with mining activity and in doing so, further explore possible determinants in communities of low- and middle-income countries. Four databases were systematically searched and articles were included if the study targeted adults residing in proximity to mining activity, and measured individual or community-level health or well-being outcomes. Narrative synthesis was conducted. Twelve articles were included. Mining was perceived to influence health behaviours, employment conditions, livelihoods and socio-political factors, which were linked to poorer health outcomes. Family relationships, mental health and community cohesion were negatively associated with mining activity. High-risk health behaviours, population growth and changes in vector ecology from environmental modification were associated with increased infectious disease prevalence. This review presents the broader health and well-being outcomes and their determinants, and strengthens the evidence to improve measurement and management of the public health implications of mining. This will support the mining sector to make sustainable investments, and support governments to maximise community development and minimise negative impacts.     

Do discharge codes underestimate hospitalisation due to heart failure? Validation study of hospital discharge coding for heart failure

BACKGROUND: Discharge codes are frequently used to describe hospital activity related to heart failure (HF). OBJECTIVES: To determine whether discharge codes for HF underestimated or overestimated hospital activity related to HF. DESIGN: Patients with atrial fibrillation (AF), who commonly have HF, were identified and their case notes reviewed to identify cases of HF missed by discharge codes. PARTICIPANTS AND METHODS: Patients admitted between November 1997 and January 1998 with either HF or AF. Identification of HF and AF by ICD10 hospital discharge codes. Identification of additional cases of AF from a central hospital-wide ECG database. RESULTS: We identified 330 cases with an ICD 10 code for HF, of which 43 (13%) were deemed to be miscoded, 32 patients (10%) were classified as possible, 39 (12%) as probable and 216 (65%) as definite HF. Results were similar whether or not HF was the primary discharge diagnosis. We identified 452 patients with AF, of whom 45 (10%) were classified as probable and 193 (43%) as definite HF. 129 (54%) of these cases had no diagnostic discharge code for HF. ICD 10 discharge codes for HF were correct in 77% of cases but identified only 66% of patients with probable or definite HF in this analysis. Screening of other diagnoses would have identified further cases of HF. CONCLUSIONS: Hospital discharge codes substantially underestimate hospital events related to HF in the UK.     

Capture-recapture estimates of problem drug use and the use of simulation based confidence intervals in a stratified analysis

STUDY OBJECTIVE: To establish the prevalence of problem drug use in the 10 local authorities within the Metropolitan County of Greater Manchester between April 2000 and March 2001. SETTING AND PARTICIPANTS: Problem drug users aged 16-54 resident within Greater Manchester who attended community based statutory drug treatment agencies, were in contact with general practitioners, were assessed by arrest referral workers, were in contact with the probation service, or arrested under the Misuse of Drugs Act for offences involving possession of opioids, cocaine, or benzodiazepines. DESIGN: Multi-sample stratified capture-recapture analysis. Patterns of overlaps between data sources were modelled in a log-linear regression to estimate the hidden number of drug users within each of 60 area, age group, and gender strata. Simulation methods were used to generate 95% confidence intervals for the sums of the stratified estimates. MAIN RESULTS: The total number of problem drug users in Greater Manchester was estimated to be 19 255 giving a prevalence of problem drug use of 13.7 (95% CI 13.4 to 15.7) per 1000 population aged 16-54. The ratio of men to women was 3.5:1. The distribution of problem drug users varied across three age groups (16-24, 25-34, and 35-54) and varied between the 10 areas. CONCLUSIONS: Areas in close geographical proximity display different patterns of drug use in terms of prevalence rates and age and gender patterns. This has important implications, both for future planning of service provision and for the way in which the impact of drug misuse interventions are evaluated.     

Using economic analyses for local priority setting

Introduction

Standard methods of economic analysis may not be suitable for local decision making that is specific to a particular population.

Background

We describe a new three-step methodology, termed ‘population cost-impact analysis’, which provides a population perspective to the costs and benefits of alternative interventions. The first two steps involve calculating the population impact and the costs of the proposed interventions relevant to local conditions. This involves the calculation of population impact measures (which have been previously described but are not currently used extensively) — measures of absolute risk and risk reduction, applied to a population denominator. In step three, preferences of policy-makers are obtained. This is in contrast to the QALY approach in which quality weights are obtained as a part of the measurement of benefit.

Methods

We applied the population cost-impact analysis method to a comparison of two interventions — increasing the use of β-adrenoceptor antagonists (β-blockers) and smoking cessation — after myocardial infarction in a scaled-back notional local population of 100 000 people in England. Twenty-two public health professionals were asked via a questionnaire to rank the order in which they would implement four interventions. They were given information on both population cost impact and QALYs for each intervention.

Results

In a population of 100 000 people, moving from current to best practice for β-adrenoceptor antagonists and smoking cessation will prevent 11 and 4 deaths (or gain of 127 or 42 life-years), respectively. The cost per event prevented in the next year, or life-year gained, is less for β-adrenoceptor antagonists than for smoking cessation. Public health professionals were found to be more inclined to rank alternative interventions according to the population cost impact than the QALY approach.

Discussion

The use of the population cost-impact approach allows information on the benefits of moving from current to best practice to be presented in terms of the benefits and costs to a particular population. The process for deciding between alternative interventions in a prioritisation exercise may differ according to the local context. We suggest that the valuation of the benefit is performed after the benefits have been quantified and that it takes into account local issues relevant to prioritisation. It would be an appropriate next step to experiment with, and formalise, this part of the population cost-impact analysis to provide a standardised approach for determining willingness to pay and provide a ranking of priorities.

Conclusion

Our method adds a new dimension to economic analysis, the ability to identify costs and benefits of potential interventions to a defined population, which may be of considerable use for policy makers working at the local level.