The HIV-epidemic among drug addicts in Norway

Up to 1996, 368 persons in Norway (population 4.3 million) had been reported as being HIV-infected because of intravenous drug use. 72 of these had developed AIDS and 59 had died from AIDS. HIV-testing is very common among drug users in Norway and new cases are rarely detected at treatment centres or at autopsy. Some 15-30 cases may still be undiagnosed. HIV spread very rapidly among drug users in Norway in 1984 and 1985, by around 100 new cases per year. Since then, the annual incidence has decreased from 30-40 cases in 1986 to 10-15 in 1995. Although the drug users seldom shared syringes even before the advent of the HIV epidemic, we believe that the public rehabilitation programmes, needle exchange programmes and health information have contributed to control HIV in this group. We expect an annual incidence of 10-15 cases the next five years.     

A simulation model of the dynamics of HIV transmission in intravenous drug users

The complex dynamics of HIV transmission and subsequent progression to AIDS make the use of traditional mathematical modeling techniques problematic. In a previous paper for this journal, Leslie and Brunham established the utility of a nonmathematical simulation language in modeling HIV transfer under conditions similar to those found among homosexual males. This study considers the application of such an approach in modeling HIV spread among intravenous drug users (IDUs) injecting within a "shooting gallery," a location providing a common needle supply to a large number of users. Modeling HIV transmission in this population involves not only consideration of heterogeneity in partnership selection, but also of the fact that spread of the virus is not directly from person to person, but via injection equipment. The General Purpose Simulation System was used to create a hypothetical cohort of IDUs, drawing from a common needle supply. Following introduction of an index case, the HIV infection rate in this cohort was followed over 5 simulated years. The model was then used to consider the effects of systematic variation in the frequency of injection and needle-cleaning behavior.     

Multiple imputation method for estimating incidence of HIV infection. The Multicenter Prospective HIV Study

BACKGROUND: CD4+ T-lymphocyte (CD4) and platelet counts are good predictors of the 'maturity' of HIV infection and can be used to impute the date of infection/seroconversion in individuals for whom this date is unknown. METHODS: Data from the Italian Seroconversion Study were used to develop a Weibull regression model for time since seroconversion as a function of the haematologic markers. The model was used to impute time since HIV infection/seroconversion in individuals from a prevalent cohort, recruited through the Lazio regional HIV surveillance system. RESULTS: The range of the imputed calendar times of infection/seroconversion in 2599 HIV prevalent individuals was 1972-1992; the earliest seroconversions occurred among injecting drug users (IDU). The peak of incidence was reached in 1986 with 340 seroconversions. Among males, the estimated median time from seroconversion to HIV diagnosis was shorter in IDU (30 months) as compared to non-IDU (36 months). This difference was smaller for females (26.6 versus 28.4 in IDU and non-IDU, respectively). CONCLUSIONS: This method permits the estimation of population-based curves of HIV incidence, using data from surveillance. The results support the hypotheses of an early spread of the epidemic among IDU in the Lazio region, and of shorter lead times in this population.     

HIV infection among male prisoners in South Australia, 1989 to 1994

The prevalence of human immunodeficiency virus (HIV) in male prisoners in South Australia from July 1989 to June 1994 was ascertained from a repeated cross-sectional study. We also compared the criminological and demographic characteristics and histories of drug use of 39 HIV-infected prisoners and a randomly selected sample of 86 uninfected prisoners admitted at the same time. The numbers of HIV-infected prisoners in prison in any month ranged from 4 to 12. Prevalence among the total prison population ranged from 0.4 per cent to 1.4 per cent, and among the subpopulation of injecting drug users from 1.25 per cent to 4.36 per cent. Many HIV-infected prisoners continued after their diagnosis to have lifestyles that resulted in imprisonment. Infected prisoners were significantly older, had spent longer in prison and were more likely to be users of heroin (OR = 13.1) and methadone (OR = 25.4) than controls. Infection with HIV among South Australian prisoners has been continuous since at least the mid-1980s. The recidivism among many of the infected prisoners contributes to the variation in prevalence but also raises concerns about their management. Greater effort to minimise the recidivism of the HIV-infected prisoners could reduce the prevalence of HIV in the prison population.     

Russia: sex, drugs, and AIDS and MSF

The first case of HIV infection in Russia was detected in 1987, there have since been 142 million HIV tests in the country, and 196 and 1535 new HIV cases were reported in 1995 and 1996, respectively. By 2000, the Ministry of Health forecasts that there will be 800,000 HIV-positive people in the country. It is culturally accepted in Russia to use drugs intravenously. There has been a rapid rise in the number of IV drug users in Russia, with an estimated 100,000 users in Moscow forming an important core group for HIV transmission, and similar numbers of users in Leningrad, Kalinigrad, and Rostov. Russian IV drug users are mainly aged 15-25 years who lead regular lives, attend school, and socialize freely with non-users, including having sexual relationships. Such behavior among IV drug users facilitates the rapid spread of HIV to the rest of society. Ketamine is popular among schoolchildren, who inject it intramuscularly, while homemade IV drugs also abound. High levels of IV drug use, a health system in a state of collapse, a growing incidence and prevalence of sexually transmitted diseases (STDs), and government inexperience with the HIV epidemic mean that an HIV epidemic in Russia is inevitable. Medecins Sans Frontieres has launched an HIV prevention campaign together with the government.     

New minimal substrate structural requirements in the enzymatic peroxidation of alkenes with soybean lipoxygenase

A longitudinal study was conducted to investigate the association between human immunodeficiency virus (HIV) infection, history of major depressive disorder (MDD), and persistent or recurrent MDD among intravenous drug users. Psychiatric disorders were assessed in a sample of HIV-positive (HIV+) and HIV-negative (HIV-) intravenous drug users every 6 months for 3 years. Results indicated that HIV status and baseline MDD independently predicted persistent or recurrent episodes of MDD after gender, drug use, ethnicity, income, and the presence other psychiatric disorders were controlled statistically. Among HIV+ intravenous drug users with baseline MDD, 90% experienced at least one subsequent episode of MDD and 47% experienced at least three subsequent episodes of MDD. However, less than 40% of intravenous drug users with current MDD received treatment for emotional problems. These findings indicate that intravenous drug users with HIV infection and a history of MDD are at considerable risk for future episodes of MDD or recurrent MDD, and that increased provision of treatment for intravenous drug users with MDD may be necessary.     

A 12-year study (1975-1986) of mortality in methadone-maintenance patients: selected demographic characteristics and drug-use patterns of AIDS and non-AIDS-related deaths

This paper describes changes in demographic characteristics and drug use patterns of persons who died while enrolled in a New York City methadone-maintenance program during the years preceding and subsequent to the AIDS epidemic. Persons dying from AIDS were more likely to be younger, Hispanic, and male than those dying from other causes. Drug use increased during the 12-year study period, and the spread of the HIV infection among drug users may be reflected in an increased use of injectable drugs.     

Prevalence of HIV infection and HIV risk behaviors associated with living place: on-the-street homeless drug users as a special target population for public health intervention

The study described here examined the prevalence of HIV infection as a function of place of residence and high-risk behaviors in six subpopulations of out-of-treatment drug injectors and crack cocaine users who participated in the National Institute on Drug Abuse (NIDA) Cooperative Agreement project. The subpopulations were blacks, Hispanics, and non-Hispanic whites sampled separately by gender. The research asked three questions: (a) Is the HIV infection rate higher among the on-the-street homeless than among those in other places of residence? (b) Do high-risk drug-related behaviors differ by housing status? and (c) What are the joint effects of high-risk drug-related behaviors and housing status on the probability of HIV infection? Overall, on-the-street homeless had a significantly higher HIV+ rate (19.0%) than the study population as a whole (11.2%). Rates differed by gender and race, with exceptionally high HIV+ rates for on-the-street homeless Hispanic males (29%) and females (32%) and for on-the-street homeless black females (38%). Having used drug works previously used by a HIV-infected person was a strong predictor of HIV+ status, as was frequency of drug injections and crack use. Having multiple sex partners was also a significant risk behavior. Findings argue against considering on-the-street homelessness as equivalent to shelter dwelling or aggregated homelessness for purposes of the AIDS epidemic. On-the-street homeless drug users were at strong risk for acquisition and transmission of HIV infection and therefore in need of targeted-racially relevant, ethnically relevant, and gender-relevant-public health interventions to help prevent the spread of AIDS.     

The short-term health outcome of out-patient rheumatology consultations in relation to rationing: a pilot study

Although Bombay (Mumbai) appears to be the main focus for acquired immunodeficiency syndrome (AIDS) in India, rapid spread has occurred through other major cities as well. The first AIDS patient in the northern state of Punjab was reported in May 1987. The present study, spanning a decade, shows that the incidence in high-risk groups increased from 3 per 1000 in 1987 to 59 per 1000 in 1997, 73% of the cases being in the third and fourth decades of life, i.e. the most productive years. The male to female ratio was 3.1:1, and 29% of the patients had the full-blown disease. A total of 80.5% acquired the infection heterosexually and only 2% of the patients were intravenous drug users. The percentage of patients acquiring infection through blood, blood products, and haemodialysis dropped from 20% in 1987 to 5% in 1997, but the cumulative figure was still 12%. The intervention programme launched by the National AIDS Control Organization (NACO) appears to have had little impact on the epidemic. There is an urgent need therefore for more interactive programmes that include education concerning the modes of spread, course, financial implications and fatal outcome of the disease, instead of passive dissemination of information by posters and the media.     

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.     

Primary HIV infection--a public health opportunity

Primary human immunodeficiency virus (HIV) infection should be considered a key target for HIV prevention activities. Mathematical models suggest that the primary HIV infection interval makes a disproportionate contribution to the HIV epidemic, perhaps accounting for as many as half of the existing infections at any point in time. If this is true, primary infection presents a special window of opportunity within which to exert a maximum impact on the spread of HIV. A combination of biological, behavioral, and social factors may account for the influence of primary infection on the HIV epidemic. HIV prevention measures can be focused on each of these factors. Biologically, detecting individuals early in the course of infection and offering treatment can reduce viral load and possibly an individual's infectiousness. Behaviorally, counseling newly infected persons about the importance of adopting safer practices may instill prevention behaviors at a critical time. Socially, using a network approach to notify persons exposed to those with primary infections can dampen the amplification effect of rapid HIV spread through high-risk environments. By focusing prevention efforts on the primary HIV infection interval, public health officials could increase their leverage in slowing the HIV epidemic.     

Cryptosporidiosis among HIV positive intravenous drug users in Malaysia

A study conducted at the Tampin Drug Rehabilitation Center in Malaysia established a high prevalence (23%) of asymptomatic carriers of Cryptosporidium among exposed HIV positive intravenous drug users (IVDUs). A majority of them were young adults and among the ethnic groups, the Malay HIV positive inmates had the highest prevalence of Cryptosporidium infection.     

Combining HIV and AIDS surveillance: an experience from an Italian region

BACKGROUND: Surveillance systems based on the reporting of AIDS cases do not provide a completely up to date picture of the trend of the HIV epidemic, stressing the need for systems based on the diagnosis of HIV infection. However, implementation of these systems has been hindered by low feasibility, poor access to HIV testing, and problems related to confidentiality. The advantages and disadvantages of the two systems and of combined use were explored by comparing and integrating information from AIDS and HIV testing registries in a region of Northern Italy. METHODS: Linkage of AIDS and HIV testing registries allowed the annual number of incident and prevalent infections to be calculated. For linked cases, concordance of exposure category was determined. RESULTS: Up to the end of 1995, 2186 AIDS cases and 5306 HIV-positive individuals were diagnosed. Linkage identified 1212 individuals reported to both registries. From 1990 to 1995, annual AIDS incidence steadily increased, while incidence of new HIV diagnoses decreased. The AIDS-to-AIDS-free ratio among those infected decreased from 1:5.6 in 1989 to 1:4.2 in 1995. The proportion of women and noninjecting drug users was higher among AIDS-free cases than among AIDS cases. The concordance of the exposure category was high (K = 0.70; 95% CI: 0.67-0.74), but it varied by exposure category; the highest concordance was for injecting drug users. CONCLUSIONS: Integrated use of the information provided by these surveillance systems allowed us to better understand and foresee the AIDS epidemic dynamics. The data also suggested that the reliability of information on exposure category may vary among categories.     

AIDS prevention strategies for ethnic-racial minority substance users.

African Americans and Latinos account for 29% and 16%, respectively, of persons with AIDS, yet collectively represent less than 20% of the US population. Although rates of HIV transmission have slowed among gay Anglo men, there is less evidence to indicate that patterns of transmission have been altered among Black and Hispanic drug users. Risk factors for HIV transmission among drug users are described, and sociocultural aspects of these risk behaviors are discussed. The advantages and disadvantages of various approaches to reducing the spread of HIV among drug users and their associates are considered, particularly as they apply to ethnic–racial minorities. Brief examples are provided of how existing theories of behavior change can be applied in Hispanic and African-American communities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

HIV-1 genetic subtype A/B recombinant strain causing an explosive epidemic in injecting drug users in Kaliningrad

OBJECTIVES: To investigate the molecular epidemiology and genetic structure of the virus strain(s) causing an outbreak of HIV-1 infection in the Kaliningrad province of the Russian Federation and to investigate the relationship of this outbreak to some other emerging HIV-1 epidemics in the countries of the former Soviet Union. DESIGN: A molecular epidemiological investigation was conducted in the city of Kaliningrad amongst individuals recently diagnosed as HIV-1-positive. Samples were also collected from neighbouring Lithuania and from the Ukraine. METHODS: Incident and population data was collected from official health statistics in Kaliningrad. A standardized questionnaire was administered to newly diagnosed individuals to assess risk factors for HIV-1 infection. For genotyping, two regions of the virus (env C2-V3 and gag NCp7) were directly sequenced. RESULTS: The number of newly diagnosed individuals testing seropositive for HIV-1 infection in Kaliningrad rose from less than one per month to more than 100 per month during the period of July-October 1996. A total of 1335 new infections were identified between 1 July 1996 and 30 June 1997. The main reported risk factor for HIV-1 infection (80%) was injecting drug use, in particular with a locally produced opiate. Sequence analysis of patient viruses in Kaliningrad (n = 50) showed that the epidemic was caused by a highly homogenous HIV-1 strain, recombinant between the genetic subtypes A and B. Comparison with subtype A strains prevalent amongst injecting drug users (IDU) in the Ukraine showed that one of these strains was the direct subtype A parent of the epidemic A/B recombinant strain in Kaliningrad. CONCLUSIONS: The HIV-1 epidemic in Kaliningrad probably started from a single source, with rapid spread of the virus through the IDU population. The origin of the epidemic strain is a recombination event occurring between the subtype A strain virus prevalent among IDU in some southern CIS countries, and a subtype B strain of unknown origin.     

Current status of HIV infection in Yunnan Province of China

In cooperation with the Chinese Academy of Preventive Medicine and Yunnan Province Provincial Office for AIDS Control and Prevention, we studied the current status of HIV infection intravenous drug users (IVDUs) and other high risk groups in Yunnan province of China. As of the end of 1995, 1,807 HIV cases were officially reported (Positive rate was 0.6%), of which 1,278 (77.9%) were IVDUs, and 24 were their spouses. The majority of cases were found among the Dai minority male farmers near Ruili which borders on Myammar, but HIV also appears to be spreading among the Han people. HIV antibody positive rates among commercial sex workers, pregnant women and blood donors were 0.2%, 0.07% and 0.04%, respectively. A system for surveillance of HIV has been developed, but preventive strategies to cope with HIV epidemic are not sufficient. As HIV/AIDS is now a global issue, (1) the integration and coordination of such preventive strategies in cooperation with community health workers, (2) general health education for condom use promotion and (3) care of psychological vulnerable person such as IVDUs, should be developed.     

Infection of sheep with adult and larval Ostertagia circumcincta: gastrin

OBJECTIVE: To determine the prevalence, incidence and risk factors for Mycobacterium tuberculosis infection, as well as to assess TB knowledge and attitudes, among a group of known drug users in a city with low TB incidence (11.3 per 100,000 in 1995). METHODS: Patients of an urban drug treatment facility enrolled in opioid substitution, opioid antagonist and other drug treatment programs were screened for TB, including tuberculin skin testing and standardized data collection on TB risk factors. A subsample of clients was interviewed about TB knowledge and attitudes. RESULTS: Between 1 June 1995 and 31 May 1996, 1055 individuals were screened. The prevalence of infection was 15.7% (CI: 13.2-18.2%). PPD positivity was associated with older age (per annum, OR = 1.08, CI: 1.05-1.11), non-white race (OR = 2.81, CI: 1.72-4.60), foreign birth (OR = 4.24, CI: 2.35-7.62) and a history of injecting drug use (OR = 1.89, CI: 1.14, 3.12). The incidence of infection was 2.9 per 100 person-years (CI: 1.8-4.7). Thirty-two per cent of 79 drug users interviewed about TB knowledge and attitudes thought TB could be prevented by bleaching or not sharing needles/syringes. Fifty-one per cent thought anyone with a positive TB skin test was contagious. CONCLUSION: M. tuberculosis infection was common in this population and associated with injecting drugs and several demographic factors. The incidence of new infection was relatively low. In this non-endemic environment, the detection and treatment of latent infection are important aspects of TB control. Misconceptions about TB transmission were also widespread in this population. Drug treatment programs can play a key role by undertaking screening programs that educate about TB and identify infected subjects who would benefit from preventive therapy.     

Demographic impact of the HIV epidemic in Thailand

OBJECTIVE: To assess the impact of the HIV epidemic on the demographic development of the Thai population. METHODS: A deterministic mathematical model was used to predict simultaneously epidemiological and demographic processes. Partial differential equations express the relationships between biological, behavioural and demographic variables. The model allows the evaluation of different sexual mixing patterns, variable transmission probabilities and incubation times. Validity analysis was performed by generating antecedent HIV prevalence patterns among military recruits and pregnant women. RESULTS: On the national level in Thailand we predict that the cumulative number of people in Thailand with HIV infection will exceed 1 million by 1999; the number of deaths from AIDS will be 555000 by the year 2000 but will not reach 1 million until after the year 2014. Without the HIV epidemic the population growth rate was estimated at 1.3% per annum until 1995, after which a decline to 0.9% by 2005 is predicted. The HIV epidemic started to affect the population growth rate by 0.026% per year in 1991, and the difference is predicted to rise to about 0.12% per year during the period 1995-2000, to decline to 0.06% in 2005 and then to disappear. In the mid-1990s HIV affected mainly the 15-35-year-old age group, but over time younger and older age groups have been affected as a result of perinatal transmission, and a decline in fertility as well as ageing of the 15-35-year-old birth cohort. Because of HIV, in 2000 there will be 612000 (1%) fewer people than expected and by 2010, 1140000 fewer (1.6%). We predict that the demographic impact of the HIV epidemic in the northern region will follow the same pattern, but with greater severity. Here, the effect on the population growth rate and the population age distribution is likely to be twice as high as at the national level. CONCLUSIONS: It is estimated that 1 million Thais will be infected with HIV by the year 2000 and an almost equal number will have died of AIDS by the year 2014. Although these numbers seem high, their direct and indirect effects on the demographic structure of the Thai population are small. However, at a regional level, for example in the northern region, the effect of the HIV epidemic may be more severe.     

Chronic eosinophilic pneumonia successfully treated with suplatast tosilate

STUDY OBJECTIVE: To review the epidemiology of hepatitis C virus (HCV) infection among injecting drug users (IDUs) in Australia, and consider needs for further research and prevention policies and programmes. DESIGN: (1) Review of the results of surveillance for HCV; (2) review of published literature on prevalence, incidence, and risk factors for HCV among IDUs; and (3) reconstruction of incidence rates from prevalence studies of HCV in IDUs. SETTING AND PARTICIPANTS: Field and clinic based studies of IDUs in Australia. MAIN RESULTS: HCV has been present at high prevalences (of the order of 60-70%) in populations of Australian IDUs since at least 1971. Duration of injecting and main drug injected were the main predictors of seropositivity, the latter possibly a surrogate for frequency of injecting and both together as surrogate for cumulative numbers of times injected. Risk of infection begins with first injection and continues as long as injecting does. Current incidence is approximately 15 per 100 person years, and up to 40 per 100 person years in some subpopulations. Incidence may have decreased through the 1980s as a result of behaviour change in relation to HIV, as it has for hepatitis B, but not significantly so. CONCLUSIONS: Control of HCV infection in Australia will depend on effectiveness of measures to control HCV spread among IDUs. This will be a greater challenge than the control of HIV in this population has been. Needs identified include improved surveillance, especially for recently acquired infection, better understanding of exact transmission modes, and urgent improvement in prevention strategies.