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ABSTRACT Estimates of chronic hepatitis B virus (HBV) prevalence and critically the amount of infection that is undiagnosed or unlinked to care are uncertain—even in countries like UK where vertical transmission and overall prevalence are very low. In the absence of country of birth data, we aim to estimate HBV prevalence through combining public health surveillance data on antenatally screened women by ethnic group and multipliers generated from non‐antenatally screened populations by ethnic group with English population denominators. Of 714,287 women aged 16–49 years with ethnic group data tested as part of antenatal care between 2015 and 2021, 4174 (0.6%) were HBsAg‐positive; 94% in people of ethnic groups other than White British. Of 1,447,467 people tested for HBsAg with ethnic group data from other testing sources (primary and secondary care excluding occupational health and renal services), 27,628 (1.9%) were HBsAg‐positive; 87% in people of ethnic groups other than White British. We estimate that the overall number and prevalence of people with chronic hepatitis B in England is 268,767 (95% CI: 227,896–314,044) and 0.58% (95% CI: 0.50–0.68). Approximately two‐thirds were male, one‐third female, and 68% were aged under 50. We estimate that over 83% of HBV infections are in people of ethnic groups other than White British, with 23% in people from Black ethnic groups, 21% from other White ethnic groups and 19% in Asian ethnic groups. These estimates are the first step towards establishing whether England can meet World Health Organisation targets to eliminate HBV as a public health problem—using methods that can also be used by other countries. [ABSTRACT FROM AUTHOR]

Introduction: People who inject drugs are at high risk of blood‐borne infections. We describe the epidemiology of HIV among people who inject drugs in England, Wales, and Northern Ireland (EW&NI) since 1981. Methods: National HIV surveillance data were used to describe trends in diagnoses (1981–2019), prevalence (1990–2019), and behaviours (1990–2019) among people who inject drugs aged ≥15 years in EW&NI. HIV care and treatment uptake were assessed among those attending in 2019. Results: Over the past four decades, the prevalence of HIV among people who inject drugs in EW&NI remained low (range: 0.64%–1.81%). Overall, 4978 people who inject drugs were diagnosed with HIV (3.2% of cases). Diagnoses peaked at 234 in 1987, decreasing to 78 in 2019; the majority were among white men born in the UK/Europe (90%), though the epidemic diversified over time. Late diagnosis (CD4 <350 cells/µl) was common (2010–2019: 52% [429/832]). Of those who last attended for HIV care in 2019, 97% (1503/1550) were receiving HIV treatment and 90% (1375/1520) had a suppressed viral load (<200 copies/ml). HIV testing uptake has steadily increased among people who inject drugs (32% since 1990). However, in 2019, 18% (246/1404) of those currently injecting reported never testing. The proportion of people currently injecting reporting sharing needles/syringes decreased from 1999 to 2012, before increasing to 20% (288/1426) in 2019, with sharing of any injecting equipment at 37% (523/1429). Conclusion: The HIV epidemic among people who inject drugs in EW&NI has remained relatively contained compared with in other countries, most likely because of the prompt implementation of an effective national harm reduction programme. However, risk behaviours and varied access to preventive interventions among people who inject drugs indicate the potential for HIV outbreaks. [ABSTRACT FROM AUTHOR]

Direct‐acting antiviral (DAA) therapy for anybody with viraemic HCV infection has been scaled‐up in England since 2017. To assess early impacts, we investigated trends in, and factors associated with, HCV viraemia among people who inject drugs (PWID). We also examined trends in self‐reported treatment access. Bio‐behavioural data from an annual, national surveillance survey of PWID (2011–2018) estimated trends in viraemic prevalence among HCV antibody‐positive PWID. Multivariable logistic regression identified characteristics independently associated with viraemia. Trends in treatment access were examined for PWID with known infection. Between 2011 and 2016, viraemic prevalence among antibody‐positive PWID remained stable (2011, 57.7%; 2016, 55.8%) but decreased in 2017 (49.4%) and 2018 (50.4%) (both p < 0.001). After adjustment for demographic and behavioural characteristics, there remained significant reduction in viraemia in 2017 (adjusted odds ratio [aOR] 0.79, 95% CI 0.65–0.94) and 2018 (aOR 0.79, 95% CI 0.66–0.93) compared to 2016. Other factors associated with viraemia were male gender (aOR 1.68, 95% CI 1.53–1.86), geographical region, injecting in past year (aOR 1.26, 95% CI 1.13–1.41), imprisonment (aOR 1.14, 95% CI 1.04–1.31) and homelessness (aOR 1.17, 95% CI 1.04–1.31). Among non‐viraemic PWID with known infection, the proportion reporting ever receiving treatment increased in 2017 (28.7%, p < 0.001) and 2018 (38.9%, p < 0.001) compared to 2016 (14.5%). In conclusion, there has been a small reduction in HCV viraemia among antibody‐positive PWID in England since 2016, alongside DAA scale‐up, and some indication that treatment access has improved in the same period. Population‐level monitoring and focus on harm reduction is critical for achieving and evaluating elimination. [ABSTRACT FROM AUTHOR]

Background: During 2009‐2010, pandemic influenza A (H1N1) pdm09 virus (pH1N1) infections in England occurred in two epidemic waves. Reasons for a reported increase in case‐severity during the second wave are unclear. Methods: We analysed hospital‐based surveillance for patients with pH1N1 infections in England during 2009‐2010 and linked national data sets to estimate ethnicity, socio‐economic status and death within 28 days of admission. We used multivariable logistic regression to assess whether changes in demographic, clinical and management characteristics of patients could explain an increase in ICU admission or death, and accounted for missing values using multiple imputation. Results: During the first wave, 54/960 (6%) hospitalised patients required intensive care and 21/960 (2%) died; during the second wave 143/1420 (10%) required intensive care and 55/1420 (4%) died. In a multivariable model, during the second wave patients were less likely to be from an ethnic minority (OR 0.33, 95% CI 0.26‐0.42), have an elevated deprivation score (OR 0.75, 95% CI 0.68‐0.83), have known comorbidity (OR 0.78, 95% CI 0.63‐0.97) or receive antiviral therapy ≤2 days before onset (OR 0.72, 95% CI 0.56‐0.92). Increased case‐severity during the second wave was not explained by changes in demographic, clinical or management characteristics. Conclusions: Monitoring changes in patient characteristics could help target interventions during multiple waves of COVID‐19 or a future influenza pandemic. To understand and respond to changes in case‐severity, surveillance is needed that includes additional factors such as admission thresholds and seasonal coinfections. [ABSTRACT FROM AUTHOR]

Background and Aims: Indirect estimation methods are required for estimating the size of populations where only a proportion of individuals are observed directly, such as problem drug users (PDUs). Capture–recapture and multiplier methods are widely used, but have been criticized as subject to bias. We propose a new approach to estimating prevalence of PDU from numbers of fatal drug‐related poisonings (fDRPs) using linked databases, addressing the key limitations of simplistic 'mortality multipliers'. Methods: Our approach requires linkage of data on a large cohort of known PDUs to mortality registers and summary information concerning additional fDRPs observed outside this cohort. We model fDRP rates among the cohort and assume that rates in unobserved PDUs are equal to rates in the cohort during periods out of treatment. Prevalence is estimated in a Bayesian statistical framework, in which we simultaneously fit regression models to fDRP rates and prevalence, allowing both to vary by demographic factors and the former also by treatment status. Results: We report a case study analysis, estimating the prevalence of opioid dependence in England in 2008/09, by gender, age group and geographical region. Overall prevalence was estimated as 0.82% (95% credible interval = 0.74–0.94%) of 15–64‐year‐olds, which is similar to a published estimate based on capture–recapture analysis. Conclusions: Our modelling approach estimates prevalence from drug‐related mortality data, while addressing the main limitations of simplistic multipliers. This offers an alternative approach for the common situation where available data sources do not meet the strong assumptions required for valid capture–recapture estimation. In a case study analysis, prevalence estimates based on our approach were surprisingly similar to existing capture–recapture estimates but, we argue, are based on a much more objective and justifiable modelling approach. [ABSTRACT FROM AUTHOR]

Persons with chronic hepatitis C (HCV) infection are at increased risk of end‐stage liver disease (ESLD) and hepatocellular carcinoma (HCC). The impact of hepatitis treatment scale‐up and elimination strategies on ESLD and HCC incidence is a critical measure of progress towards WHO targets. Data from national laboratory surveillance of HCV diagnoses were linked to inpatient care records in Hospital Episode Statistics (HES). For persons first diagnosed with HCV between 1998 and 2016, we describe the characteristics of those with ESLD and HCC and estimate incidence. Of persons diagnosed with HCV between 1998 and 2016 (104 674), 9.1% (9525) had an admission for ESLD and 2.5% (2610) for HCC. The majority of persons with ESLD and HCC were male (70.7% and 82.7%) and of white ethnicity (89.9% and 82.7%). Crude incidence of ESLD and HCC admission was 10.4 and 3.2 per 1000 person‐years, respectively. When compared to 2011‐2013, incidence of ESLD and HCC admissions in 2014‐2017 were lower (ESLD incidence rate ratio [IRR]: 0.81; 95% Confidence interval [CI]: 0.76‐0.86; HCC IRR: 0.90; 95% CI: 0.82‐1.00, P =.045). Data linkage showed considerable underreporting of HCV in HES coding for ESLD and HCC (16.0% and 11.3%, respectively). In conclusion, we found a decline in incidence of ESLD and HCC‐related inpatient admissions since 2011‐2013. Linked analysis is required for the continued monitoring of ESLD and HCC inpatient incidence. However, HES data quality issues around completeness of identifiers contribute to uncertainty in linkage and may limit our ability to robustly monitor progress towards WHO elimination goals. [ABSTRACT FROM AUTHOR]

Summary: In England, 160 000 individuals were estimated to be chronically infected with hepatitis C virus (HCV) in 2005 and the burden of severe HCV‐related liver disease has increased steadily for the past 15 years. Direct‐acting antiviral treatments can clear infection in most patients, motivating HCV elimination targets. However, the current burden of HCV is unknown and new methods are required to monitor progress. We employed a Bayesian back‐calculation approach, combining data on severe HCV‐related liver disease and disease progression, to reconstruct historical HCV incidence and estimate current prevalence in England. We explicitly modelled infections occurring in people who inject drugs, the key risk group, allowing information on the size of this population and surveillance data on HCV prevalence to inform recent incidence. We estimated that there were 143 000 chronic infections in 2015 (95% credible interval 123 000‐161 000), with 34% and 54% in those with recent and past injecting drug use, respectively. Following the planned scale‐up of new treatments, chronic infections were predicted to fall to 113 400 (94 900‐132 400) by the end of 2018 and to 89 500 (71 300‐108 600) by the end of 2020. Numbers developing severe HCV‐related liver disease were predicted to fall by at least 24% from 2015 to 2020. Thus, we describe a coherent framework to monitor progress using routinely collected data, which can be extended to incorporate additional data sources. Planned treatment scale‐up is likely to achieve 2020 WHO targets for HCV morbidity, but substantial efforts will be required to ensure that HCV testing and patient engagement are sufficiently high. People who inject drugs are at high risk of acquiring hepatitis C infection, many of whom will develop cirrhosis and severe liver disease. We use surveillance data to model this process, estimating the number of HCV‐infected people in England and predicted impact of new treatments. We estimate 143,000 people had chronic infection in 2015 and predict that this will fall to around 90,000 in 2020. [ABSTRACT FROM AUTHOR]

Collections of meta-analyses assembled in meta-epidemiological studies are used to study associations of trial characteristics with intervention effect estimates. However, methods and findings are not consistent across studies. To combine data from 10 meta-epidemiological studies into a single database, and derive a harmonized dataset without overlap between meta-analyses. The database design allowed trials to be contained in different meta-analyses, multiple meta-analyses in systematic reviews, overlapping meta-analyses between systematic reviews, and multiple references to the same trial or review. Unique identifiers were assigned to each reference and used to identify duplicate trials. Sets of meta-analyses with overlapping trials were identified and duplicates removed. Overlapping trials were used to examine agreement between assessments of trial characteristics. The combined database contained 427 reviews, 454 meta-analyses and 4874 trial results. Of these, 258 meta-analyses were unique, while for 196 at least one trial overlapped with another meta-analysis. Median kappa statistics for reliability of assessments were 0.60 for sequence generation, 0.58 for allocation concealment and 0.87 for blinding. Based on inspection of sets of overlapping meta-analyses, 91 meta-analyses containing 1344 trial results were removed. Additionally, 24 duplicated trial results were removed from 16 meta-analyses, to derive a final database containing 363 meta-analyses and 3477 unique trial results. The final database will be used to examine the combined evidence on sources of bias in randomized controlled trials. The strategy used to remove overlap between meta-analyses may be of use for future empirical research. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Insulin-like growth factors (IGF-I, IGF-II) and their binding proteins (IGFBP-1-6) play a key role in cell proliferation, differentiation and apoptosis, suggesting possible involvement in carcinogenesis. Several epidemiological studies show associations of IGFs with prostate cancer. We searched the published literature for all studies relating levels of IGFs or IGFBPs with prostate cancer. We performed random effects meta-analysis to calculate summary odds ratios. The number of studies (prostate cancer cases) included in each meta-analysis were 42 (7,481) IGF-I; 10 (923) IGF-II; 3 (485) IGFBP-1; 5 (577) IGFBP-2; 29 (6,541) IGFBP-3 and 11 (3,545) IGF-1:IGFBP-3 ratio. The pooled odds ratios (95% confidence intervals) per standard deviation increase in peptide were: IGF-I, OR = 1.21 (1.07, 1.36); IGF-II, OR = 1.17 (0.93, 1.47); IGFBP-1, OR = 1.21 (0.62, 2.33); IGFBP-2, OR = 1.18 (0.90, 1.54); IGFBP-3, OR = 0.88 (0.79, 0.98); IGFI:IGFBP-3 ratio, OR = 1.10 (0.97, 1.24). For all exposures, there was substantial heterogeneity (all I [ABSTRACT FROM AUTHOR]

Leukoplakia is an asymptomatic, potentially malignant change in the oral mucosa. Previous studies have reported that smoking and betel quid chewing are associated with increased risk of leukoplakia; few studies have reported on these associations in populations where betel quid does not contain tobacco. We conducted a case-control study nested in a cross-sectional study in Papua New Guinea and a systematic review of studies that included chewers of betel quid without tobacco. Our study recruited 1,670 adults. We recorded betel quid chewing and smoking. The prevalence of leukoplakia was 11.7%. In the nested case-control study of 197 cases and 1,282 controls, current betel chewing was associated with increased risk of leukoplakia with an adjusted odds ratio for current chewers of 3.8 (95% CI 1.7, 8.4) and in the heaviest chewers of 4.1 (95% CI 1.8, 9.1) compared to non-chewers. Current smoking was associated with an increased risk of leukoplakia with an adjusted odds ratio for current smokers of 6.4 (95% CI 4.1, 9.9) and amongst heaviest smokers of 9.8 (95% CI 5.9, 16.4) compared to non-smokers. The systematic review identified 5 studies examining risk of leukoplakia associated with betel quid chewing in populations where betel quid did not contain tobacco and that controlled for smoking. In studies that adjusted for smoking, the combined random effect odds ratio was 7.9 (95% CI 4.3, 14.6) in betel quid chewers. The results of this study and systematic review of similar studies provide evidence of the role of betel quid not containing tobacco and leukoplakia. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Presents a study of numbers, sighting distances, and behavior of seals during a nearshore seismic program off northern Alaska in July-September 1996. Observations from the seismic vessel at all periods (day and night) when airguns operated and many periods without airguns; Sighting rates; Seal behavior; Description of methods for estimating numbers of seals which potentially affected by the seismic program; Discussion of the effectiveness of monitoring and mitigation; View that there is an urgent need for more data on effects of strong seismic pulses on seals.

The authors reflect on the use of multiple parameter evidence synthesis (MPES) to estimate people who inject drugs (PWID) and drug use. The authors state that diverse information sources can be integrated by MPES into a single coherent model which was said to be similar to systematic reviews. The authors state that MPES was also used for other infections including chlamdyia and toxoplasmosis.