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Sheila M Bird

Publications and source records attributed to Sheila M Bird.

16 recordsLinked to original sources
PubMed2005

Prior information in behavioral capture-recapture methods: demographic influences on drug injectors' propensity to be listed in data sources and their drug-related mortality.

The authors present findings from a Bayesian analysis of Scotland's four primary capture-recapture data sources for 2000 that was carried out to estimate numbers of current injecting drug users by region (Greater Glasgow vs. elsewhere in Scotland), sex (male vs. female), and age group (15-34 years vs. > or =35 years). A secondary goal of the analysis was to obtain Bayesian estimates and credible intervals for the demographic influences on Scotland's drug-related death rate per 100 current injectors. Incorporation of informative priors altered the models with highest posterior probability. Expert opinion on how demography influenced Scottish drug injectors' propensity to be listed in different data sources was taken into account, along with external information about European injectors' drug-related death rates and male:female ratios. Higher drug-related mortality was confirmed in older drug injectors and those outside of Greater Glasgow. Female injectors' lower drug-related death rate was not sustained beyond 34 years of age. The authors recommend that demographic influences be accommodated in behavioral capture-recapture estimation, especially when it is a prelude to secondary analysis, such as the analysis of drug-related death rates presented here.

Adolescent↗
PubMed2005

Modeling the current and future disease burden of hepatitis C among injection drug users in Scotland.

Quantitative estimates of the current and future burden of hepatitis C virus (HCV) disease are required to plan a public health response to the HCV epidemic with regard to both prevention and treatment. A forward projection model was used to estimate the numbers of both current and former injecting drug users (IDUs) who acquired HCV and progressed to moderate and severe disease in Glasgow and Scotland during 1960-2030. The model was designed to synthesize information on the incidence and cessation of injecting drug use, the incidence of HCV infection among IDUs, the rate of HCV disease progression, and the annual number of IDUs developing HCV-related decompensated cirrhosis. During 2003, a total of 17,400 and 42,900 HCV-infected IDUs were estimated in Glasgow and Scotland, respectively; this compares with approximately 5,000 and 13,900 diagnosed, respectively, and 13,200 and 32,200 with chronic HCV, respectively. The number of IDUs developing HCV-related decompensated cirrhosis in Scotland is estimated to double between 2000 and 2020. As many as 16% and 27% of former IDUs in 2005 aged 30-39 and 40-49 years, respectively, were estimated to have moderate disease, which highlights the potential benefit of targeting HCV testing at former IDUs who belong to these age groups. In conclusion, the identification and treatment of a larger proportion of former IDUs with HCV disease and education about the importance of minimal alcohol consumption are needed to help achieve a greater impact on the future morbidity and mortality of this disease.

Hepatitis C↗
PubMed2005

Influence of alcohol on the progression of hepatitis C virus infection: a meta-analysis.

BACKGROUND & AIMS: A convincing, yet inconsistent, pattern has emerged that demonstrates increased progression of HCV-related liver disease with heavy alcohol use. The aim was to perform a meta-analysis to quantify the effect of alcohol on cirrhosis risk among persons infected with HCV. METHODS: A meta-analysis of 20 articles, involving more than 15,000 HCV chronically infected persons, published between 1995 and 2004 was undertaken to explore the relationship between advanced liver disease and the consumption of alcohol. RESULTS: The pooled relative risk of cirrhosis associated with heavy alcohol intake (defined in the range of at least 210-560 g per week) was 2.33 (95% confidence interval, 1.67-3.26) by the random effects model. The risk of HCV-related liver disease associated with heavy alcohol intake increased with severity of the outcome; the lowest (1.63; 95% confidence interval, 1.22-2.17) and highest (3.54; 2.14-5.85) pooled relative risk estimates were obtained for advanced fibrosis and decompensated cirrhosis, respectively. The regression effect of alcohol might, however, be underestimated in studies investigating the risk of HCV-related cirrhosis because they necessarily include patients undergoing liver biopsy and could therefore under-represent heavy alcohol users. CONCLUSIONS: The evidence overwhelmingly shows a worsened outcome for those with chronic HCV and concurrent alcohol use. Studies varied widely in their definition of significant alcohol intake, and so the true threshold above which alcohol accelerates HCV disease progression remains uncertain. Alcohol consumption should be minimized as much as possible in those who have chronic HCV until a safe threshold is more definitively determined.

Alcohol Drinking↗
PubMed2004

Sudden rise in uptake of hepatitis B vaccination among injecting drug users associated with a universal vaccine programme in prisons.

Hitherto, services have failed to deliver the UK Government's 1988 recommendation to vaccinate injecting drug users (IDUs) against hepatitis B virus (HBV). In April 1999, the Scottish Prison Service implemented an initiative to offer HBV vaccination to all inmates; we sought to determine the impact of this initiative on the IDU population. Among community-recruited IDUs (who had injected for < or =5 years) in Glasgow, vaccine uptake was significantly higher among those surveyed in 2001-2002 (52% of 387) than in 1993 (16% of 166), 1994 (19% of 138) or January-March 1999 (15% of 128); of the 2001-2002 vaccinees, 56% had been vaccinated in prison. Our results indicate that the universal offer of vaccination to all prisoners, within two years of the initiative's implementation, has had a dramatic impact on uptake among IDUs.

Adult↗
PubMed2003

Drug-related deaths by region, sex, and age group per 100 injecting drug users in Scotland, 2000-01.

BACKGROUND: In 2000 and 2001, there were 292 and 332 drug-related deaths in Scotland, respectively. Of the 332 people who died in 2001, 65 were of female sex, 80 were younger than 25 years, and 112 were older than 34 years. We assessed the effect of region, sex, and age group on drug-related deaths in Scotland per 100 injecting drug users. METHODS: We used published regional estimates of current injecting drug users (n=22805), their sex (30% female) and age distribution (8% older than 34 years in mid-1990s), or corresponding data for problem drug users (21% older than 34 years in 2000) to compare observed with expected drug-related deaths by region, sex, and age group per 1000 population or per 100 injecting drug users. FINDINGS: Regional population-based expectations fitted poorly to observed drug-related deaths, but those based on injecting drug users fitted tolerably. Drug-related deaths in 2001 per 100 injecting drug users were significantly lower in female (0.9 [95% CI 0.6-1.1]) than in male drug users (1.5; 1.3-1.7). They were between two and six times more frequent per 100 injecting drug users older than 34 years than younger than 25 years, depending on whether current injecting drug users' age distribution was assumed to be the same as problem drug users' or as injecting drug users' in the mid-1990s (2.1 [1.7-2.5] or 5.3 [4.3-6.3], respectively). INTERPRETATION: Older and male injecting drug users were at highest risk of drug-related death. Injecting drug users' age distribution should be assessed and compared across countries.

Adolescent↗
PubMed2003

Male drugs-related deaths in the fortnight after release from prison: Scotland, 1996-99.

AIMS: To assess if 15-35-year-old males released after 14 + days' imprisonment in Scotland, 1996-99, had a higher drugs-related death rate in 2 weeks after release than during subsequent 10 weeks; higher than expected death rate from other causes; and if drugs-related deaths in the first fortnight were three times as many as prison suicides. DESIGN: Confidential linkage of ex-prisoner database against deaths. SETTING: Scotland's male prisons and young offenders' institutions during July to December 1996-99; 19 486 index releases after 14+ days' incarceration. MEASUREMENTS: Relative risk of drugs-related death in the first 2 weeks after release (34 deaths) versus subsequent 10 weeks (23). Other causes of death (21) relative to expectation. Drugs-related deaths in first 2 weeks after release relative to suicides in prison (12). FINDINGS: Drugs-related mortality in 1996-99 was seven times higher (95% CI: 3.3-16.3) in the 2 weeks after release than at other times at liberty and 2.8 times higher than prison suicides (95% CI: 1.5-3.5) by males aged 15-35 years who had been incarcerated for 14+ days. We estimated one drugs-related death in the 2 weeks after release per 200 adult male injectors released from 14 + days' incarceration. Non-drugs-related deaths in the 12 weeks after release were 4.9 times (95% CI: 2.8-7.0) the 4.3 deaths expected. CONCLUSION: Investment in, and evaluation of, prison-based interventions is needed to reduce substantially recently released drugs-related deaths.

Adolescent↗
PubMed2003

European Union's rapid TSE testing in adult cattle and sheep: implementation and results in 2001 and 2002.

After the discovery of variant Creutzfeldt-Jakob disease (vCJD), scientific advances quickly led to post-mortem tests to identify late-stage bovine spongiform encephalopathy (BSE) disease. These were first used in Switzerland in 1999 for active BSE surveillance of a) fallen and emergency-slaughter bovines (risk stock) and b) 5% sample of routinely slaughtered cattle over 30 months of age. In 1999 and 2000, Switzerland's estimated 103 BSE positives per 1000000 adult cattle put it in the same BSE risk classification as UK and Portugal. In July 2000, the European Union's Scientific Steering Committee published its methodology (and first vetted results) for geographical BSE risk (GBR) assessment in cattle. Member states with no BSE cases found themselves, on rational assessment, classified as GBR III (BSE likely but not confirmed, or confirmed at a lower level). Because of Europe's thus highly assessed BSE risks, active BSE surveillance of adult cattle in all member states began in January 2001 using one of three validated post-mortem tests. Implementation was variable across member states in January to March 2001 but, where operational, active surveillance was typically achieved for around 13300 routinely slaughtered and 1000 risk stock per month per 1000000 adult cattle; BSE positive rates were 60 and 600 per 1000000 routinely slaughtered and risk cattle, respectively. By the second half of 2001, active BSE surveillance was operating reasonably in most member states, although anomalies persisted. Performance and results for July to December 2001 and for January to June 2002 are considered in detail. The BSE positive rate decreased substantially in UK, Portugal and Ireland between semesters, whereas Spain's rates increased for both routinely slaughtered and risk bovines. Based on 1450000 routinely slaughtered and 135000 risk stock as standard, France could have expected 153 BSE positives in July to December 2001 (109 in January to June 2002); Italy 154 (67); and Germany only 39 (48). When sample-based surveillance data were scaled up and combined with clinical BSE cases, Great Britain's BSE positives were estimated at around 400 per 1000000 adult cattle in 2002 compared with over 1000 per 1000000 adult cattle in 2000. Age distributions for cattle subject to active BSE surveillance have been underexploited. The major transmissible spongiform encephalopathy (TSE) which affects sheep and goats is scrapie. Passive surveillance of scrapie is associated with substantial under-reporting. Susceptibility to scrapie depends strongly on sheep genotype; but resistance to scrapie does not necessarily confer resistance of sheep to BSE. Because of uncertainty about the true prevalence of scrapie-infected adult sheep and concern that BSE in sheep may be missed, the European Union pre-empted its planned evaluation of rapid post-mortem TSE tests in sheep by requiring the rapid TSE testing of small ruminants from April 2002 with one of the three cattle-validated tests. Basic requirements for active TSE surveillance in sheep were: random sample of 6000 fallen sheep and of 60000 routinely slaughtered adult native sheep to be tested per member state by end March 2003. Lower surveillance targets were set for countries with under 1000000 adult sheep. Adequately to map scrapie-susceptible genotypes and identify resistant genotypes, a random sample of 500 routinely slaughtered native adult sheep was to be genotyped, together with each TSE rapid test positive adult sheep and two sets of three suitably sampled controls. By the end of August 2002, when 41% of the initial surveillance time had elapsed, only 20% of the European joint target for routinely slaughtered adult sheep had been completed, but that for fallen sheep was exceeded. Except in Ireland, the upper 95% confidence bound on TSE prevalence exceeded 500 per 1000000 routinely slaughtered adult sheep in reporting-compliant countries with more than 1000000 adult sheep. The UK, Greece, Italy and France were likely to approach the goal of 100 TSE rapid test positives on completion of their assigned first-year surveillance target for sheep. Results from the recommended genotyping of TSE positive adult sheep and controls for use in inferring differential TSE-positive susceptibility by genotype are awaited. Only by genotyping 5000-50000 TSE-positive adult sheep, a massive undertaking even on the European scale, will it become clear whether scrapie resistance is relative rather than absolute. This paper details Europe's quantitative evolution in TSE surveillance.

Animals↗
PubMedDate not supplied

Attributable testing for abnormal prion protein, database linkage, and blood-borne vCJD risks.

CONTEXT: National prospective collection of tonsillar tissue to be tested anonymously for abnormal lymphoreticular accumulation of prion protein (PrP) was approved to begin in the UK in 2004. The UK is not, however, testing autopsy specimens attributably for abnormal PrP (PrP(SC)) so that recipients at risk after a blood transfusion from, or exposed to surgical instruments from, a deceased carrier of variant Creutzfeldt-Jakob disease (vCJD) can be followed up to quantify transmission risks. In Switzerland, surveillance for subclinical vCJD includes unconsented testing in autopsies: consented testing of tonsillar tissue is potentially attributable to interrupt human-to-human vCJD transmission or treat it. STARTING POINT: The UK announced its first case of probable blood-borne vCJD transmission in December, 2003, and first detected a case of probable blood-borne subclinical vCJD in July, 2004. To reduce the possible risk of onward transmission to other people, UK patients who had received vCJD-implicated plasma products are being contacted. They, and their general practitioner, are asked to inform anyone giving them medical, surgical, or dental treatment, and the patients must refrain from donating blood, tissues, or organs. WHERE NEXT? Prudent additional surveillance options for human PrP(SC)--particularly at autopsy or to sanction the release of quarantined operation sets pending effective decontamination--can be costed by reference to results for cattle and sheep. Some ethical or legal impediments to the UK's potentially-attributable testing for PrP(SC) may yet be rued.

Animals↗