Assessing the feasibility of hepatitis C virus vaccine trials: Results from the Hepatitis C Incidence and Transmission Study-community (HITS-c) vaccine preparedness study

Efficacy trials of preventive hepatitis C virus (HCV) vaccine candidates raise challenging scientific and ethical issues. Based on data from the first 3 years of a community-based prospective observational study – the Hepatitis C Incidence and Transmission Study-community (HITS-c) – this paper examines the feasibility of conducting trials of candidate HCV vaccines with people who inject drugs (PWID) in Sydney, Australia. Of the 166 PWID confirmed HCV antibody negative and eligible for enrolment, 156 (94%) completed baseline procedures. Retention was high, with 89% of participants retained at 48 weeks and 76% of participants completing at least 75% of study visits within 2 weeks of schedule. The rate of primary HCV infection was 7.9/100 py (95% CI 4.9, 12.7). Of the 17 incident cases, 16 completed at least one follow-up assessment and 12 (75%) had evidence of chronic viraemia with progression to chronic HCV infection estimated to be 6/100 py. Power calculations suggest a chronic HCV infection rate of at least 12/100 py (primary HCV infection rate 16/100 py) will be required for stand-alone trials of highly efficacious candidates designed to prevent chronic infection. However, elevated primary HCV infection was observed among participants not receiving opioid substitution therapy who reported heroin as the main drug injected (26.9/100 py, 95% CI 14.5, 50.0) and those who reported unstable housing (23.5/100 py, 95% CI 7.6, 72.8), daily or more frequent injecting (22.7/100 py, 95% CI 12.2, 42.2) and receptive syringe sharing (23.6/100 py, 95% CI 9.8, 56.7) in the 6 months prior to baseline. These data suggest that it is possible to recruit and retain at-risk PWID who adhere to study protocols and that modification of eligibility criteria may identify populations with sufficiently high HCV incidence. Results support the feasibility of large multi-centre HCV vaccine trials, including in the Australian setting.     

云南省德宏州美沙酮维持治疗者丙型肝炎病毒新发感染率及影响因素研究

目的了解云南省德宏州美沙酮维持治疗(MMT)就诊者中丙型肝炎病毒(HCV)新发感染率及其危险因素.方法将2005年6月至2012年3月德宏州所有入组MMT且HCV检测阴性的海洛因成瘾者作为研究对象,观察其HCV阳转情况,计算HCV新发感染率并运用Cox比例风险回归模型分析其影响因素.结果共2390名对象符合队列纳入标准.其中731人(30.6%)入组MMT后未接受随访检测;1659人(69.4%)接受过至少一次随访检测,累计随访观察3509.13人年,期间99人发生HCV抗体阳转,HCV新发感染率为2.82/100人年.2006-2011年HCV新发感染率依次为3.62/100人年、5.36/100人年、6.71/100人年、2.56/100人年、1.90/100人年和0.44/100人年.运用Cox比例风险模型多因素分析显示,在控制混杂因素的影响后,待业/无业、入组前曾注射毒品、入组时HIV检测确认阳性者在MMT治疗期间新发HCV感染风险显著高于农民、入组前未注射毒品和入组时HIV检测阴性者(HR =2.02,95%CI:1.18 ～ 3.48;HR=9.05,95%CI:5.49 ～ 14.93;HR=2.12,95%CI:1.37 ～ 3.56).结论德宏州MMT就诊者中HCV新发感染率自2009年起逐年下降,但职业为待业/无业、入组前曾注射毒品和HIV感染者其HCV新发感染的风险较高.     

BMI与恶性肿瘤发病风险的前瞻性队列研究

目的利用大规模人群队列研究,探讨BMI与恶性肿瘤发病的关联性及其强度。方法采用2006年开滦集团体检人群队列(收集基线调查时人口学、生活方式和身高、体重等测量指标信息).通过主动和被动随访相结合方式,收集肿瘤发病、死亡等结局信息。排除随访时问<1年的新发病例后,采用多因素Cox比例风险回归模型分析低体重、超重和肥胖与肿瘤发病的风险比(HR)和95%CI,调整变量包括年龄、受教育程度、吸烟、饮酒和HBsAg(仅在肝癌中调整)：对男性肺癌、肝癌和女性乳腺癌分别按吸烟、HBsAg和绝经状态分层后纳入模型重新分析。结果至2011年12月31 Et,随访人群纳入队列133 273人,其中男性106 630人(80.0l%)、女性26 643人(19.99%),共随访570 531.02人年,平均随访时间为4.28年。男性低体重(BMI<18.5kg／m2)2 387人(2.24%),正常体重(BMI 18.5～23.9 kg／m2)45 090人(42.29%),超重(BMI 24.0-27.9 kg／m2)43 774人(41.05%),肥胖(BMI≥28.0 kg／m2)15 379人(14.42%);女性低体重858人(3.22%),正常体重14 037人(52.69%),超重8 507人(31.93%),肥胖3 241人(12.16%)。共收集肿瘤新发病例1 647例,其中男性1 348例,女性299例。多因素Cox比例风险回归模型分析表明,与正常体重者相比,男性低体重者胃癌(a／／R=3.82,95%CI：1.97。7.38)和肝癌(棚月=3.00,95%C1：1.36～6.65)的发病风险增加;男性肥胖(aHR=2.75,95%C1：1.25.6.06)和超重(a／／R=1.98,95%CI：1.03,3.82)者结肠癌发病风险增加;男性膀胱癌病例中,超重为保护性因素(aHR=0.44,95%CI：0.23-0,84);男性肺癌病例中,超重和肥胖均为保护性因素(超重：aHR=0.59,95%Cl：O.46一O.76;肥胖：aHR=0.64,95%CI：O.44。O.92)。而较之体重正常女性,女性肥胖者乳腺癌(aHR=1.86,95%C1：1.05～3.31)的发病风险增加：分层分析显示：刘‘于男性肺癌,超重对不吸烟者和吸烟者均起保护作用(小吸烟者：aHR=0.50,95%C1：O.35-0.72;吸烟者：aHR=0.70,95%CI：0.50一O.98),肥胖仅对男性不吸烟者起保护作用(a／／R=0 57,95%CI：O.33～O.97),而男性吸烟者与肺癌发病风险不存在相关性(aHR=0.72,95%C1：0.43～1.21)。按女性绝经状态分层后,肥胖增加了绝经后乳腺癌的发病风险(aHR=1.97,95%CI：1.01～3.82),而与绝经前乳腺癌的发病风险之间的关联无统计学意义：结论BMI与恶性肿瘤发病风险的相关性因肿瘤不同而存在差异。低体重与男性胃癌和肝癌的发病风险存在相关性,肥胖与男性结肠癌、女性绝经后乳腺癌和卵巢癌的发病风险存在相关性,而超重可能刘‘于男性肺癌和膀胱癌发病起到保护作用,肥胖可能对于非吸烟男性肺癌发病起到保护作用。     

Hepatitis C virus incidence among injecting drug users on opioid replacement therapy

OBJECTIVE: To determine hepatitis C virus (HCV) incidence among injecting drug users (IDUs) receiving opioid replacement therapy (ORT). METHODS: A retrospective cohort study was established in a primary care drug dependency treatment clinic. The cohort included all IDUs who commenced ORT after January 1996 with an initial anti-HCV antibody negative result and repeat testing prior to July 2003. HCV incidence was estimated for all subjects, with further comparison among those with continuous versus interrupted ORT. RESULTS: Fifty-four subjects were initially HCV antibody negative and had repeat testing. Five cases of HCV antibody seroconversion occurred during a total follow-up period of 131.1 person years (py), an incidence of 3.8/100 py (95% CI 1.2-8.9/ 100 py). Four seroconversions occurred in the subgroup with interrupted ORT (n=20), an incidence of 7.4/100 py (95% CI 2.0-18.9/100 py), compared with one seroconversion in the subgroup with continuous ORT (n=34), an incidence of 1.3/100 py (95% CI 0.03-7.3/100 py). CONCLUSIONS: HCV incidence among IDUs receiving ORT in our clinic was relatively low. Those IDUs without interruptions to their treatment appeared to be at particularly low risk of HCV infection. These findings support the role of ORT in HCV prevention for IDUs.     

Patient-Reported Outcomes During and After Hepatitis C Virus Direct-Acting Antiviral Treatment Among People Who Inject Drugs

ObjectivesPeople who inject drugs (PWID) are at a high risk of hepatitis C virus (HCV) infection. HCV cure is associated with improved patient-reported outcomes (PROs), but there are little data among PWID. This study aimed to assess the change in PROs during and after HCV direct-acting antiviral (DAA) treatment.MethodsThis analysis used data from 2 clinical trials of DAA treatment in PWID. PROs assessed included health-related quality of life, social functioning, psychological distress, housing, and employment. Generalized estimating equations and group-based trajectory modeling were used to assess changes in PROs over time.ResultsNo significant changes in the 3-level version of EQ-5D scores, EQ visual analogue scale scores, social functioning, psychological distress, and housing were observed over the 108-week study period. There was a significant increase in the proportion of participants employed (18% [95% confidence interval (CI) 12%-23%] at baseline to 28% [95% CI 19%-36%] at the end of the study). Participants were more likely to be employed at 24 weeks and 108 weeks after commencing treatment. Having stable housing increased the odds of being employed (odds ratio 1.70; 95% CI 1.00-2.90). The group-based trajectory modeling demonstrated that most outcomes remained stable during and after DAA treatment.ConclusionsAlthough no significant improvement was identified in health-related quality of life after HCV DAA treatment, there was a modest but significant increase in employment during study follow-up. The study findings support the need for multifaceted models of HCV care for PWID addressing a range of issues beyond HCV treatment to improve quality of life.     

Sexual Contact as Risk Factor for Campylobacter Infection,Denmark

Campylobacteriosis is a disease of worldwide importance, but aspects of its transmission dynamics, particularly risk factors, are still poorly understood. We used data from a matched case-control study of 4,269 men who have sex with men (MSM) and 26,215 controls, combined with national surveillance data on Campylobacter spp., Salmonella spp., and Shigella spp., to calculate matched odds ratios (mORs) for infection among MSM and controls. MSM had higher odds of Campylobacter (mOR 14, 95% CI 10–21) and Shigella (mOR 74, 95% CI 27–203) infections, but not Salmonella (mOR 0.2, 95% CI 0–13), and were less likely than controls to have acquired Campylobacter infection abroad (χ² = 21; p<0.001). Our results confirm that sexual contact is a risk factor for campylobacteriosis and also suggest explanations for unique features of Campylobacter epidemiology. These findings provide a baseline for updating infection risk guidelines to the general population.     

Housing Instability and Incident Hypertension in the CARDIA Cohort

Housing instability, a growing public health problem, may be an independent environmental risk factor for hypertension, but limited prospective data exist. We sought to determine the independent association of housing instability in early adulthood (year 5, 1990–1991) and incident hypertension over the subsequent 15 years of follow-up (years 7, 10, 15, and 20) in the Coronary Artery Risk Development in Young Adults (CARDIA) study (N = 5,115). Because causes of inadequate housing and its effects on health are thought to vary by race and sex, we hypothesized that housing instability would exert a differential effect on incident hypertension by race and sex. At year 5, all CARDIA participants were asked about housing and those free of hypertension were analyzed (N = 4,342). We defined housing instability as living in overcrowded housing, moving frequently, or living doubled up. Of the 4,342 participants, 8.5 % were living in unstable housing. Across all participants, housing instability was not associated with incident hypertension (incidence rate ratio (IRR), 1.1; 95 % CI, 0.9–1.5) after adjusting for demographics, socioeconomic status, substance use, social factors, body mass index, and study site. However, the association varied by race and sex (p value for interaction, <0.001). Unstably housed white women had a hypertension incidence rate 4.7 times (IRR, 4.7; 95 % CI, 2.4–9.2) that of stably housed white women in adjusted analysis. There was no association among white men, black women, or black men. These findings suggest that housing instability may be a more important risk factor among white women, and may act independently or as a marker for other psychosocial stressors (e.g., stress from intimate partner violence) leading to development of hypertension. Studies that examine the role of these psychosocial stressors in development of hypertension risk among unstably housed white women are needed.     

Housing conditions and adverse birth outcomes among Indigenous people in Canada

ObjectivesPoor housing conditions and household crowding have been identified as important health concerns for Indigenous populations in many countries but have not been explored in relation to adverse birth outcomes in these populations. We investigated housing conditions and adverse birth outcomes in a nationally representative sample of Indigenous people in Canada.MethodsData were from a cohort of births between May 2004 and May 2006 created by linking birth and infant death registration data with the 2006 Canadian census. Log-binomial regression was used to examine associations between housing variables (persons per room and needed household repairs) and three adverse birth outcomes: preterm birth (PTB), small-for-gestational-age (SGA) birth, and infant mortality. Separate regression models were run for First Nations, Métis and Inuit mothers, with adjustment for parity and parental socio-economic variables.ResultsNeed for major household repairs was associated with a slightly increased risk of PTB among First Nations and Métis mothers (adjusted RRs 1.12 and 1.13, respectively; 95% CI 0.94–1.34 and 0.89–1.44, respectively) and a moderately increased risk of infant death in all three groups (aRR = 1.69, 95% CI 1.00–2.85). Household crowding was also associated with a slightly elevated risk of PTB in all three groups (aRR = 1.10, 95% CI 0.95–1.29) and with an increased risk of infant mortality among First Nations (aRR = 1.57, 95% CI 0.97–2.53).ConclusionThis study highlights the need to improve understanding of links between housing conditions and perinatal health outcomes in Indigenous populations, including examining cause-specific infant mortality in relation to housing characteristics.Supplementary InformationThe online version contains supplementary material available at 10.17269/s41997-021-00527-2.     

Ongoing susceptibility to hepatitis B virus infection among people who inject drugs in Sydney

Objective: To determine hepatitus B virus (HBV) vaccine‐induced immunity and infection in people who inject drugs (PWID) screened for a prospective observational study in Sydney. Method: 227 PWID completed a brief demographic and risk behaviour survey and provided blood for HBV, hepatitis C virus antibody (anti‐HCV) and HIV testing. Correlates of HBV status were examined in the overall sample and HBV protective immunity was assessed in a subset of anti‐HCV negative participants (n=124); a population with typically shorter injecting histories but at potentially high risk for HBV and HCV. Results: Almost half (45%) were susceptible to HBV infection. Only 84 (37%) had evidence of vaccine‐induced immunity (HBV surface antibody ≥10 mLU/mL and HBV core antibody (anti‐HBc) negative) and 40 (18%) tested anti‐HBc positive, of whom 7 (4%) were also HBV surface antigen positive. HBV vaccine‐induced immunity was associated with a history of incarceration (AOR 1.98; 95% CI 1.05–3.71, p=0.034) while HBV infection was associated with prior HCV infection (AOR 6.29; 95% CI 2.29–17.24, p<0.001). Among anti‐HCV negative participants, HBV vaccine‐induced immunity was significantly lower among those who reported lifetime receptive syringe sharing (AOR 0.38; 95% CI 0.15–0.95, p=0.04). Conclusions: Low HBV vaccine coverage among PWID suggests that improved efforts to increase vaccination uptake and completion are still required as those of greatest risk are not being adequately identified and immunised. Implications: Novel immunisation strategies, including contingency management approaches focused on new initiates and adolescents at risk of injecting, should be expanded.     

Tattooing in prison: a risk factor for HCV infection among inmates in the Quebec's provincial correctional system

Purpose

To determine the prevalence of hepatitis C virus (HCV) and identify related risk factors among inmates in Quebec provincial prisons.

Prevalence and Incidence of HCV Infection among Vietnam Heroin Users with Recent Onset of Injection

HCV infection continues to spread at an alarming rate among IDU populations. The available evidence suggests that HCV is acquired relatively quickly following onset of injection. However, there are few prospective studies of HCV acquisition, particularly among IDU populations in resource-poor settings. A sample of young male heroin injectors with recent onset of injection (<4 years) was recruited in Hanoi, Vietnam for a prospective assessment of the early course of injection (n = 179). Both behavioral and biological assessments (including detailed retrospective assessment of injection initiation) were conducted at baseline and repeated at 6-month intervals for a period of 16 months. Variables associated with HCV infection (p value < 0.05) in bivariate analyses were considered for inclusion in logistic regression models to identify risk factors independently associated with HCV infection. HCV incidence was calculated by using the incidence density approach and was expressed in terms of person-years of observation. The baseline of prevalence of HCV was 46%. HCV significantly increased in relation to time since first injection, from 30% in subjects with ≤10 months of injection risk to 70% in subjects with ≥30 months injection risk (p value = 0.0005). In multivariate logistic regression analysis, increasing age, incarceration in a drug detention facility (OR = 2.54; 95%CI 1.05, 6.15), and time since first injection remained significantly associated with HCV infection. Use of injection as primary mode of administration (OR = 2.56; 95%CI 0.98, 6.69) achieved marginal significance. After 16 months of follow-up, the incidence rate of HCV was 23.35 per 100 person-years and the mean time between first injection and first positive HCV test was 1.2 years. HCV is acquired much more rapidly among new injector populations than previously recognized, demonstrating the need for early behavioral intervention among new heroin-user populations. Particularly critical are interventions that target new heroin user populations, including interventions that improve understanding of viral transmission dynamics, that promote alternative strategies for drug sharing, and that delay initiation of injection.     

The Cedar Project: high incidence of HCV infections in a longitudinal study of young Aboriginal people who use drugs in two Canadian cities

ABSTRACT: BACKGROUND: Factors associated with HCV incidence among young Aboriginal people in Canada are still not well understood. We sought to estimate time to HCV infection and the relative hazard of risk factors associated HCV infection among young Aboriginal people who use injection drugs in two Canadian cities. METHODS: The Cedar Project is a prospective cohort study involving young Aboriginal people in Vancouver and Prince George, British Columbia, who use illicit drugs. Participants' venous blood samples were drawn and tested for HCV antibodies. Analysis was restricted to participants who use used injection drugs at enrolment or any of follow up visit. Cox proportional hazards regression was used to identify independent predictors of time to HCV seroconversion. RESULTS: In total, 45 out of 148 participants seroconverted over the study period. Incidence of HCV infection was 26.3 per 100 person-years (95% Confidence Interval [CI]: 16.3, 46.1) among participants who reported using injection drugs for two years or less, 14.4 per 100 person-years (95% CI: 7.7, 28.9) among participants who had been using injection drugs for between two and five years, and 5.1 per 100 person-years (95% CI: 2.6,10.9) among participants who had been using injection drugs for over five years. Independent associations with HCV seroconversion were involvement in sex work in the last six months (Adjusted Hazard Ratio (AHR): 1.59; 95% CI: 1.05, 2.42) compared to no involvement, having been using injection drugs for less than two years (AHR: 4.14; 95% CI: 1.91, 8.94) and for between two and five years (AHR: 2.12; 95%CI: 0.94, 4.77) compared to over five years, daily cocaine injection in the last six months (AHR: 2.47; 95% CI: 1.51, 4.05) compared to less than daily, and sharing intravenous needles in the last six months (AHR: 2.56; 95% CI: 1.47, 4.49) compared to not sharing. CONCLUSIONS: This study contributes to the limited body of research addressing HCV infection among Aboriginal people in Canada. The HCV incidence rate among Cedar Project participants who were new initiates of injection drug use underscores an urgent need for HCV and injection prevention and safety strategies aimed at supporting young people surviving injection drug use and sex work in both cities. Young people must be afforded the opportunity to provide leadership and input in the development of prevention programming.     

Low incidences of human immunodeficiency virus and hepatitis C virus infection and declining risk behaviors in a cohort of injection drug users in Chennai, India

The authors characterized human immunodeficiency virus (HIV) and hepatitis C virus (HCV) incidence and prospective changes in self-reported risk behavior over 2 years among 1,158 injection drug users (IDUs) recruited in Chennai, India, in 2005-2006. At baseline, HIV prevalence was 25.3%, and HCV prevalence was 54.5%. Seropositive persons with prevalent HIV infection were used to estimate baseline HIV incidence by means of the Calypte HIV-1 BED Incidence EIA (Calypte Biomedical Corporation, Portland, Oregon). Longitudinal HIV and HCV incidence were measured among 865 HIV-negative IDUs and 519 HCV antibody-negative IDUs followed semiannually for 2 years. Participants received pre- and posttest risk reduction counseling at each visit. Estimated HIV incidence at baseline was 2.95 per 100 person-years (95% confidence interval (CI): 1.21, 4.69) by BED assay; observed HIV incidence over 1,262 person-years was 0.48 per 100 person-years (95% CI: 0.17, 1.03). HCV incidence over 645 person-years was 1.71 per 100 person-years (95% CI: 0.85, 3.03). Self-reported risk behaviors declined significantly over time, from 100% of participants reporting drug injection at baseline to 11% at 24 months. In this cohort with high HIV and HCV prevalence at enrollment, the authors observed low incidence and declining self-reported risk behavior over time. While no formal intervention was administered, these findings highlight the potential impact of voluntary counseling and testing in a high-risk cohort.     

Differences in Clinical Presentation With Long COVID After Community and Hospital Infection and Associations With All-Cause Mortality: English Sentinel Network Database Study

BackgroundMost studies of long COVID (symptoms of COVID-19 infection beyond 4 weeks) have focused on people hospitalized in their initial illness. Long COVID is thought to be underrecorded in UK primary care electronic records.ObjectiveWe sought to determine which symptoms people present to primary care after COVID-19 infection and whether presentation differs in people who were not hospitalized, as well as post–long COVID mortality rates.MethodsWe used routine data from the nationally representative primary care sentinel cohort of the Oxford–Royal College of General Practitioners Research and Surveillance Centre (N=7,396,702), applying a predefined long COVID phenotype and grouped by whether the index infection occurred in hospital or in the community. We included COVID-19 infection cases from March 1, 2020, to April 1, 2021. We conducted a before-and-after analysis of long COVID symptoms prespecified by the Office of National Statistics, comparing symptoms presented between 1 and 6 months after the index infection matched with the same months 1 year previously. We conducted logistic regression analysis, quoting odds ratios (ORs) with 95% CIs.ResultsIn total, 5.63% (416,505/7,396,702) and 1.83% (7623/416,505) of the patients had received a coded diagnosis of COVID-19 infection and diagnosis of, or referral for, long COVID, respectively. People with diagnosis or referral of long COVID had higher odds of presenting the prespecified symptoms after versus before COVID-19 infection (OR 2.66, 95% CI 2.46-2.88, for those with index community infection and OR 2.42, 95% CI 2.03-2.89, for those hospitalized). After an index community infection, patients were more likely to present with nonspecific symptoms (OR 3.44, 95% CI 3.00-3.95; P<.001) compared with after a hospital admission (OR 2.09, 95% CI 1.56-2.80; P<.001). Mental health sequelae were more strongly associated with index hospital infections (OR 2.21, 95% CI 1.64-2.96) than with index community infections (OR 1.36, 95% CI 1.21-1.53; P<.001). People presenting to primary care after hospital infection were more likely to be men (OR 1.43, 95% CI 1.25-1.64; P<.001), more socioeconomically deprived (OR 1.42, 95% CI 1.24-1.63; P<.001), and with higher multimorbidity scores (OR 1.41, 95% CI 1.26-1.57; P<.001) than those presenting after an index community infection. All-cause mortality in people with long COVID was associated with increasing age, male sex (OR 3.32, 95% CI 1.34-9.24; P=.01), and higher multimorbidity score (OR 2.11, 95% CI 1.34-3.29; P<.001). Vaccination was associated with reduced odds of mortality (OR 0.10, 95% CI 0.03-0.35; P<.001).ConclusionsThe low percentage of people recorded as having long COVID after COVID-19 infection reflects either low prevalence or underrecording. The characteristics and comorbidities of those presenting with long COVID after a community infection are different from those hospitalized. This study provides insights into the presentation of long COVID in primary care and implications for workload.     

How does tuberculosis relate to HIV positive and HIV negative drug users?

OBJECTIVES: (1) To compare the incidence of active tuberculosis in HIV positive and HIV negative drug users. (2) To describe the main characteristics of the tuberculosis cases. DESIGN: A prospective study was performed from 1986 to 1996 as part of an ongoing cohort study of HIV infection in Amsterdam drug users. METHODS: Data from the cohort study, including HIV serostatus and CD4-cell numbers, were completed with data from the tuberculosis registration of the tuberculosis department of the Amsterdam Municipal Health Service. Analyses were carried out with person time and survival methods. RESULTS: Of 872 participants, 24 persons developed culture confirmed tuberculosis during a total follow up period of 4000 person years (0.60 per 100 py, 95% CI: 0.40, 0.90). Nineteen cases were HIV positive (1.54 per 100 py, 95% CI: 0.86, 2.11) and five HIV negative (0.18 per 100 py, 95% CI: 0.08, 0.43). Multivariately HIV infection (relative risk: 12.9; 95% CI: 3.4, 48.8) and age above 33 years (RR: 6.8; 95% CI: 1.3, 35.0, as compared with age below 27) increased the risk for tuberculosis substantially. Additional findings were: (1) 13 of 22 pulmonary tuberculosis cases (59%) were detected by half yearly radiographic screening of the chest; (2) tuberculosis occurred relatively early in the course of HIV infection at a mean CD4 cell number of 390/microliter; (3) an estimated two thirds of the incidence of tuberculosis observed among HIV positive cases was caused by reactivation; (4) all but one patient completed the tuberculosis treatment. CONCLUSION: HIV infection increases the risk for active tuberculosis in Amsterdam drug users 13-fold. The incidence of tuberculosis in HIV negative drug users is still six times higher than in the overall Amsterdam population. In the absence of contact tracing and screening with tuberculin skin tests, periodic chest radiographic screening contributes substantially to early casefinding of active tuberculosis in Amsterdam drug users.     

Hepatitis B and C among Berlin dental personnel: incidence, risk factors, and effectiveness of barrier prevention measures

A study of 215 Berlin dentists and 108 dental assistants recruited at the 1997 Berlin Dental Society meeting assessed their occupational risk of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection. HBV vaccine coverage, and barrier prevention methods used. Among dentists, 7% (95% CI 4-11) and 0.5% (95% CI 0-3) had serological evidence of previous HBV and HCV infection, respectively. Similar figures for dental assistants were 1% (95% CI 0-5) and 0% (95% CI 0-4). Only 74% of dentists and 63% of dental assistants reported HBV vaccination. Approximately half always used gloves, eye glasses, or face masks. HBV unvaccinated dentists whose patients had HBV risk factors had a greater risk of HBV infection; those who always wore face masks were at lower risk (OR 0.2, 95% CI 0.02-0.98). These data indicate that among Berlin dentists, the HCV risk was lower than that of HBV and that face masks may have lowered the risk of HBV. The use of eye glasses or gloves did not appear to lower the risk of HBV acquisition in this population.     

Acute Lower Respiratory Infection in Childhood and Household Fuel Use in Bhaktapur,Nepal

Background: Globally, solid fuels are used by about 3 billion people for cooking. These fuels have been associated with many health effects, including acute lower respiratory infection (ALRI) in young children. Nepal has a high prevalence of use of biomass for cooking and heating.Objective: This case–control study was conducted among a population in the Bhaktapur municipality, Nepal, to investigate the relationship of cookfuel type to ALRI in young children.Methods: Cases with ALRI and age-matched controls were enrolled from an open cohort of children 2–35 months old, under active monthly surveillance for ALRI. A questionnaire was used to obtain information on family characteristics, including household cooking and heating appliances and fuels. The main analysis was carried out using conditional logistic regression. Population-attributable fractions (PAF) for stove types were calculated.Results: A total of 917 children (452 cases and 465 controls) were recruited into the study. Relative to use of electricity for cooking, ALRI was increased in association with any use of biomass stoves [odds ratio (OR) = 1.93; 95% CI: 1.24, 2.98], kerosene stoves (OR = 1.87; 95% CI: 1.24, 2.83), and gas stoves (OR = 1.62; 95% CI: 1.05, 2.50). Use of wood, kerosene, or coal heating was also associated with ALRI (OR = 1.45; 95% CI: 0.97, 2.14), compared with no heating or electricity or gas heating. PAFs for ALRI were 18.0% (95% CI: 8.1, 26.9%) and 18.7% (95% CI: 8.4%–27.8%), for biomass and kerosene stoves, respectively.Conclusions: The study supports previous reports indicating that use of biomass as a household fuel is a risk factor for ALRI, and provides new evidence that use of kerosene for cooking may also be a risk factor for ALRI in young children.     

Job strain and effort–reward imbalance as risk factors for type 2 diabetes mellitus: A systematic review and meta-analysis of prospective studies

ObjectivesThis systematic review and meta-analysis aimed to synthesize the available data on prospective associations between work-related stressors and the risk of type 2 diabetes mellitus (T2DM) among adult workers, according to the demand–control–support (DCS) and the effort–reward imbalance (ERI) models.MethodWe searched for prospective studies in PubMed, EMBASE, Web of Science, Scopus, CINHAL and PsychInfo. After screening and extraction, quality of evidence was assessed using the ROBINS-I tool adapted for observational studies. The effect estimates extracted for each cohort were synthesized using random effect models.ResultsWe included 18 studies (reporting data on 25 cohorts) in meta-analyses for job strain, job demands, job control, social support at work and ERI. Workers exposed to job strain had a higher risk of developing T2DM when compared to unexposed workers [pooled rate ratio (RR) 1.16, 95% confidence interval (CI) 1.07–1.26]. This association was robust in several supplementary analyses. For exposed women relative to unexposed women, the RR was 1.35 (95% CI 1.12–1.64). The RR of workers exposed to ERI was 1.24 (95% CI 1.08–1.42) compared to unexposed workers.ConclusionsThis is the first meta-analysis to find an effect of ERI on the onset of T2DM incidence. It also confirms that job strain increases the incidence of T2DM, especially among women.     

Major decline of hepatitis C virus incidence rate over two decades in a cohort of drug users

Injecting drug users (DU) are at high risk for hepatitis C virus (HCV) and HIV infections. To examine the prevalence and incidence of these infections over a 20-year period (1985–2005), the authors evaluated 1276 DU from the Amsterdam Cohort Studies who had been tested prospectively for HIV infection and retrospectively for HCV infection. To compare HCV and HIV incidences, a smooth trend was assumed for both curves over calendar time. Risk factors for HCV seroconversion were determined using Poisson regression. Among ever-injecting DU, the prevalence of HCV antibodies was 84.5% at study entry, and 30.9% were co-infected with HIV. Their yearly HCV incidence dropped from 27.5/100 person years (PY) in the 1980s to 2/100 PY in recent years. In multivariate analyses, ever-injecting DU who currently injected and borrowed needles were at increased risk of HCV seroconversion (incidence rate ratio 29.9, 95% CI 12.6, 70.9) compared to ever-injecting DU who did not currently inject. The risk of HCV seroconversion decreased over calendar time. The HCV incidence in ever-injecting DU was on average 4.4 times the HIV incidence, a pattern seen over the entire study period. The simultaneous decline of both HCV and HIV incidence probably results from reduced risk behavior at the population level. Charlotte H.S.B. van den Berg and ColetteSmit contributed equally to this paper