The state of hepatitis B and C in the Mediterranean and Balkan countries: report from a summit conference.

The burden of disease due to chronic viral hepatitis constitutes a global threat. In many Balkan and Mediterranean countries, the disease burden due to viral hepatitis remains largely unrecognized, including in high-risk groups and migrants, because of a lack of reliable epidemiological data, suggesting the need for better and targeted surveillance for public health gains. In many countries, the burden of chronic liver disease due to hepatitis B and C is increasing due to ageing of unvaccinated populations and migration, and a probable increase in drug injecting. Targeted vaccination strategies for hepatitis B virus (HBV) among risk groups and harm reduction interventions at adequate scale and coverage for injecting drug users are needed. Transmission of HBV and hepatitis C virus (HCV) in healthcare settings and a higher prevalence of HBV and HCV among recipients of blood and blood products in the Balkan and North African countries highlight the need to implement and monitor universal precautions in these settings and use voluntary, nonremunerated, repeat donors. Progress in drug discovery has improved outcomes of treatment for both HBV and HCV, although access is limited by the high costs of these drugs and resources available for health care. Egypt, with the highest burden of hepatitis C in the world, provides treatment through its National Control Strategy. Addressing the burden of viral hepatitis in the Balkan and Mediterranean regions will require national commitments in the form of strategic plans, financial and human resources, normative guidance and technical support from regional agencies and research.

Hepatitis C prevalence in injecting drug users in Europe, 1990-2007: impact of study recruitment setting.

Monitoring injecting drug users' (IDUs) health is challenging because IDUs form a difficult to reach population. We examined the impact of recruitment setting on hepatitis C prevalence. Individual datasets from 12 studies were merged. Predictors of HCV positivity were sought through a multilevel analysis using a mixed-effects logistic model, with study identifier as random intercept. HCV prevalence ranged from 21% to 86% across the studies. Overall, HCV prevalence was higher in IDUs recruited in drug treatment centres compared to those recruited in low-threshold settings (74% and 42%, respectively, P < 0·001). Recruitment setting remained significantly associated with HCV prevalence after adjustment for duration of injecting and recent injection (adjusted odds ratio 0·7, 95% confidence interval 0·6-0·8, P = 0·05). Recruitment setting may have an impact on HCV prevalence estimates of IDUs in Europe. Assessing the impact of mixed recruitment strategies, including respondent-driven sampling, on HCV prevalence estimates, would be valuable.

Human immunodeficiency virus among people who inject drugs: is risk increasing in Europe?

In most European Union (EU)/European Economic Area (EEA) countries, between 2010 and 2012, reports of new human immunodeficiency virus (HIV) diagnoses among people who inject drugs have been stable or declining. HIV outbreaks in Greece and Romania, first reported in 2011, continue and economic conditions hinder provision of effective response coverage. When measured against some established thresholds, prevention coverage remains inadequate in at least one-third of EU/EEA countries. Urgent consideration to scale up prevention efforts is merited.

Estimating the force of infection for HCV in injecting drug users using interval-censored data.

Injecting drug users (IDUs) account for most new HCV infections. The objectives of this study were: to estimate the force of infection for hepatitis C virus in IDUs within the interval-censoring framework and to determine the impact of risk factors such as frequency of injection, drug injected, sharing of syringes and time of first injection on the time to HCV infection. We used data from the Amsterdam Cohort Study collected in The Netherlands and focused on those individuals who were HCV negative upon entry into the study. Based on the results, the force of infection was found to vary with time of first injection. The risk of infection was higher in the first 3 years of an IDU's career, implying estimates based on single cross-sectional studies could be biased. Frequency of injection and type of drug injected were found to be highly significant predictors, whereas sharing syringes was not.

The state of hepatitis B and C in Europe: report from the hepatitis B and C summit conference*.

Worldwide, the hepatitis B virus (HBV) and the hepatitis C virus (HCV) cause, respectively, 600,000 and 350,000 deaths each year. Viral hepatitis is the leading cause of cirrhosis and liver cancer, which in turn ranks as the third cause of cancer death worldwide. Within the WHO European region, approximately 14 million people are chronically infected with HBV, and nine million people are chronically infected with HCV. Lack of reliable epidemiological data on HBV and HCV is one of the biggest hurdles to advancing policy. Risk groups such as migrants and injecting drug users (IDU) tend to be under-represented in existing prevalence studies; thus, targeted surveillance is urgently needed to correctly estimate the burden of HBV and HCV. The most effective means of prevention against HBV is vaccination, and most European Union (EU) countries have universal vaccination programmes. For both HBV and HCV, screening of individuals who present a high risk of contracting the virus is critical given the asymptomatic, and thereby silent, nature of disease. Screening of migrants and IDUs has been shown to be effective and potentially cost-effective. There have been significant advances in the treatment of HCV and HBV in recent years, but health care professionals remain poorly aware of treatment options. Greater professional training is needed on the management of hepatitis including the treatment of liver cancer to encourage adherence to guidelines and offer patients the best possible outcomes. Viral hepatitis knows no borders. EU Member States, guided by the EU, need to work in a concerted manner to implement lasting, effective policies and programmes and make tackling viral hepatitis a public health priority.

Trends in HIV and hepatitis C virus infections among injecting drug users in Europe, 2005 to 2010.

Data on newly diagnosed HIV infections and HIV prevalence in 2005 to 2010 suggest falling infection rates in injecting drug users (IDUs) in the European Union (EU). However, recent increases in HIV and hepatitis C virus (HCV) infection rates in IDUs suggest increasing injecting risks in some countries. The coverage of effective prevention measures has increased, but is still low in several countries. Overall the data suggest a continued risk of new outbreaks of HIV infection among IDUs.

Human immunodeficiency virus in injecting drug users in Europe following a reported increase of cases in Greece and Romania, 2011.

Greece and Romania reported an increased number of HIV cases among injecting drug users (IDUs) during 2011. Most European countries reported no changes in the rate of newly diagnosed cases of HIV or HIV prevalence in IDUs; however, six countries did report increases and several additional countries reported increases in injecting risk indicators or low coverage of prevention services. These indicate a potential risk for increased HIV transmission and future outbreaks unless adequate prevention is implemented.

Rebound of overdose mortality in the European Union 2003-2005: findings from the 2008 EMCDDA Annual Report.

Drug overdose is an important cause of death among young adults in Europe. According to data reported by Member States to the EMCDDA, many of the European Union countries reported a rebound in the numbers of overdose deaths in 2003-2005, following decreases in almost all reporting countries in previous years (2000 to 2003). Further investigations are needed in order to clarify the factor driving these increases and inform policies and interventions aimed at reducing these deaths.

Drug use and pregnancy - challenges for public health.

Involving pregnant drug users in drug treatment is likely to decrease the chances of pre- and perinatal complications related to drug use and to increase access to prenatal care. Timely medical intervention can effectively prevent vertical transmission of human immunodeficiency virus, hepatitis B virus as well as certain other sexually transmitted diseases, and would allow newborns infected with hepatitis C virus during birth to receive immediate treatment.

A comparison between the force of infection estimates for blood-borne viruses in injecting drug user populations across the European Union: a modelling study.

A number of studies have been conducted in injecting drug user (IDU) populations in Europe, in which the prevalence of human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV) was measured together with demographic and epidemiological information such as age and the age at first injection. A measure of the risk of becoming infected is the force of infection (FOI), defined as the per capita rate at which susceptible individuals acquire infection. The objective of this study was to estimate the FOI and its heterogeneity for HBV, HCV and HIV (where available) for IDU populations in a number of countries in Europe. Data were obtained from five countries: Belgium, the United Kingdom, Spain and Italy, and the Czech Republic, which provided two data sets. The model describes the prevalence of infection as a function of the FOI that may vary over time or duration of IDU. In addition to this, if two or more infections were being considered then a parameter describing the potential heterogeneity of the FOI within the IDU population was also estimated. The results here add to the growing evidence that new initiates to injecting are at an increased risk of blood-borne viral infection compared with more experienced IDUs. In addition, there is evidence of individual heterogeneity of FOI estimates within the overall IDU populations. This suggests that different proportions of individuals in each population are at increased risk of infection compared with the rest of the population. Future interventions should identify and target these individuals. Moreover, changes over time in individual heterogeneity estimates of IDU populations may provide an indicator for measuring intervention impacts.

HIV among injecting drug users in Europe: increasing trends in the East.

The human immunodeficiency virus (HIV) epidemic among injecting drug users (IDUs) shows different developments in different parts of the European region. In the countries of the European Union (EU) and the European Free Trade Association (EFTA), the rates of reported newly diagnosed cases of HIV infection in IDUs are mostly at stable and low levels or in decline. In contrast, those rates increased in 2007 in many of the other (eastern) countries in the World Health Organization (WHO) European Region, suggesting that the HIV epidemic among IDUs in Europe is still growing. In countries or regions where indicators of HIV incidence show upward trends, existing prevention measures may be insufficient and in need of strengthening. In the EU/EFTA region the larger availability of harm reduction measures such as opioid substitution treatment and needle and syringe programmes may have played a key role in containing the epidemic among IDUs.

Modelling the spread of HIV in social networks of injecting drug users.

OBJECTIVE: To explore the risk of a future rise of HIV prevalence in populations of injecting drug users (IDU) with low HIV prevalence but continuing risk behaviour, and to study the potential influence of prevention measures on HIV incidence. METHODS: A stochastic simulation model was used to describe a network of long-term buddy relationships in a population of IDU. HIV transmission took place when borrowing injecting equipment from an infected buddy or stranger. The probability of transmission depended on the duration of infection. Individuals remained in the population on average for 10 years. Two surveys amongst IDU in The Netherlands containing information about risk behaviour were used to estimate model parameters. We investigated the effect of different prevention strategies. RESULTS: Below a threshold sharing frequency the epidemic never takes off; above the threshold there is a large stochastic variation in prevalence. After reduction of risk behaviour, HIV prevalence decreases very slowly. Reducing sharing with strangers is more effective than reducing the overall sharing frequency. Prevention focused on new IDU greatly reduces HIV incidence. Reduction of sharing frequency in HIV-positive IDU has no significant influence on HIV incidence at HIV testing rates of 10 and 50% per year, if infectivity is highest during primary infection. CONCLUSIONS: A stabilization of HIV prevalence does not exclude the possibility of a future rise. Predictions about the future course of an epidemic are inherently uncertain. The effect of prevention programmes on HIV prevalence only becomes visible on a long time-scale. Social networks of IDU play an important role in transmission dynamics and success of prevention.

An age-period-cohort analysis of 50,875 AIDS cases among injecting drug users in Europe.

BACKGROUND: The long average incubation time from HIV infection to AIDS makes it difficult to estimate recent HIV transmission from AIDS incidence data. Age-period-cohort (APC) analysis can separate out the effects of age, calendar time and birth cohort to provide a clearer picture of transmission trends. METHODS: AIDS incidence data from 1981 to 1994 among intravenous drug users (IDU) for 12 Western European countries were used. Yearly incidences per 100,000 population or 100,000 person-years were calculated by age at diagnosis and 5-year birth cohort (1950-1954, 1955-1959, 1960-1964, 1965-1969 and 1970-1974), and corrected for reporting delay. Incidence patterns were compared between birth cohorts and countries. RESULTS: For most countries the impact was greatest on the cohort born 1960-1964. Comparing incidence patterns in the 1965-1969 to 1960-1964 cohorts suggest the epidemic has plateaued at low to intermediate levels in Austria, Greece and the North-Western European countries, and at high levels in France, Italy and Switzerland. For most countries transmission amongst the 1970-1974 as compared to the 1965-1969 cohorts could not be assessed due to small numbers and short follow-up time. In Spain the epidemic was uncontrolled with a high incidence among recent birth cohorts. In Portugal the epidemic was still at an early and expanding phase. CONCLUSIONS: The APC analysis revealed large country differences in the dynamics of the HIV/AIDS epidemic among IDU. Full interpretation of these differences is dependent on information from other sources about the local public health response and trends in drug injecting behaviours. Earlier introduction of the virus and higher prevalence of injecting drug use may explain some of the generally higher incidence in Southern European countries, but the larger part of it is most likely explained by local characteristics of drug users, such as younger age and more frequent sharing of needles and syringes, and a less effective public health response.

A comparison of different methods for estimating the prevalence of problematic drug misuse in Great Britain.

AIMS: The European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) has produced methodological guidelines for national drug prevalence estimation. This paper pilots the methods to estimate prevalence for Great Britain and provides a commentary on the methods and resulting estimates. DESIGN: Three types of methodology were used to estimate prevalence: (a) the multiple indicator (MI) method, (b) multipliers applied to (i) drug-treatment records (ii) HIV estimates and (iii) mortality statistics and (c) the British/Scottish Crime Surveys. SETTING: England, Scotland and Wales. PARTICIPANTS: Aggregated data on people recorded on databases and respondents in household surveys. MEASUREMENTS: Prevalence estimates of different forms of problematic drug use. FINDINGS: The estimates are 161,133 (range: 120,850-241,700) for people at risk of mortality due to drug overdose; 161,000-169,000 for people who have ever injected drugs; 202,000 (range: 162,000-244,000) problem opiate users and 268,000 problem drug users (all types). CONCLUSIONS: The multiple indicator method offers a comprehensive approach to estimating the prevalence of problematic drug use in the United Kingdom. Simple multiplier methods and household surveys also provide a range of estimates corresponding to different types of drug use in the United Kingdom. The current study suggests that previous national estimates of 100,000-200,000 were conservative. The new estimate of 161,000-266,000 should enable a more focused response. For further development of this method, reliable and timely estimates of anchor points are required for specific geographical areas such as cities or Drug Action Teams (DAT), as well as routine aggregation of drug indicators for these areas.

Lyme borreliosis in Dutch forestry workers.

Serum samples from 127 Dutch forestry workers and 127 matched controls were tested for antibodies against Borrelia burgdorferi in an indirect immunofluorescence assay (IFA). Those of the forestry workers were also tested by Western blotting. The forestry workers were examined clinically for evidence of Lyme borreliosis without the examiner or the workers knowing the results of the laboratory tests. Seroprevalence of B. burgdorferi antibodies among forestry workers (25/127) was significantly higher than among controls matched for age and place of residence (8/127), odds ratio 3.7 (95% CI 1.5-9.7). Of the 25 sera of forestry workers positive in the IFA, 23 reacted with at least five bacterial polypeptides in the Western blot test. According to adapted CDC criteria, seven forestry workers (6%) were classified as being a case of Lyme borreliosis. In only one of them had the diagnosis been made before this investigation. Five persons had a history of erythema migrans, one of arthritis, and one of persistent infection. We conclude that Lyme borreliosis is an occupational disease among forestry workers in the Netherlands, with a three-fold higher seroprevalence than among matched controls. The disease, often not diagnosed among this high-risk group, warrants more attention to achieve early recognition and to prevent late complications.

Laboratory-based HIV surveillance with information on exposure: importance of discriminating person-based from test-based results.

Within a surveillance programme in a Regional Public Health Laboratory anonymous information on HIV test, requesting physician and tested individual is automatically selected, regardless of test result. Thereby, personal identifiers are transformed into unique but meaningless numeric codes. Besides, requesting physicians receive a questionnaire on indication for testing (response 87%). Between April 1989 and June 1993 12,219 HIV tests were performed in 10,972 individuals. The percentage of positive tests (2.1%) was twice the percentage of positive individuals (1%). No increase in number of new infections was observed over time. Of individuals, 41.6% were tested due to third party requests (mainly insurance): HIV was demonstrated once (0.03%). Among the remainder, with medical indications, seroprevalence was 1.4%. At relatively little expense, we were able to provide valid information about patterns of HIV-testing and HIV seroprevalences among people tested in routine medical practice. Prevention of double counts proved to be important. Extension to other Dutch areas is expected.

[Prevalence of HIV infection among drug users in Zuid-Limburg]. / Prevalentie van HIV-infectie onder druggebruikers in Zuid-Limburg.

OBJECTIVES: To assess the prevalence of HIV infection among intravenous (IDU) and non-intravenous drug users in Heerlen and Maastricht (Southern Netherlands), to detect subgroups of IDU with a higher risk of HIV infection, and to assess the risk of further spread of HIV. DESIGN: Cross-sectional study. SETTING: Heerlen, Kerkrade, Brunssum and Maastricht, the Netherlands. METHODS: Between August 15 and November 25, 1994, a saliva specimen and a short questionnaire were obtained from 449 drug users (340 IDU) in Heerlen (and environs) and Maastricht. Participants were recruited through methadone care (54%), syringe exchange (16%), a street prostitution project (3%), street recruitment (23%) and other drug users (4%). RESULTS: Of the 340 IDU 33 were infected (prevalence: 10% (95% confidence interval: 7-13)), among the 109 non-IDU no infections were found (0% (0-3)). IDU making use of the syringe exchange had a higher prevalence (odds ratio 3.13 (1.37-7.61)). In logistic regression analysis, this finding could not be explained by selection on more risky injecting. One in five currently injecting IDU reported having used someone else's used needle or syringe in the last 6 months. One in five IDU had a non-drug user as steady sexual partner. In sexual contacts between steady partners condom use was low. On the basis of self-reported serostatus it appeared that some infections have taken place in the last two years. CONCLUSIONS: The prevalence of HIV infections among IDU in Heerlen and Maastricht is about 10%. IDU using the syringe exchange have a higher prevalence. This means this prevention reaches the high-risk group, but probably can not avoid all infections. The risk of further spread among IDU is high. The risk of spread to non-IDU and non-drug users is present.