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D Vlahov

Publications and source records attributed to D Vlahov.

At least 145 records · Page 8Linked to original sources
PubMed1998

Operation Red Box: a pilot project of needle and syringe drop boxes for injection drug users in East Baltimore.

We assessed the acceptability and the use of a community-based needle and syringe disposal project designed to serve injection drug users. In June 1996, three surplus U.S. mail collection boxes were painted red and used as syringe and needle drop boxes in locations with high drug use in East Baltimore. Acceptance of the drop boxes was measured by focus groups of residents, drug users, and police, held before and after project implementation. Use was measured by weekly counts of needles recovered from the red boxes. A sample of all deposited needles was randomly chosen for needle washing and subsequent HIV antibody testing. Community impact was measured by systematic surveys of needles discarded on public sidewalks, in areas with and areas without drop boxes. Before implementation, members of focus groups expressed concerns that drop boxes could convey mixed messages to youth (e.g., seeming to condone drug use), might result in increased loitering, and could further community stigmatization. After project implementation, all focus groups expressed support of project expansion. In the first 10 months, 2971 needles were collected. Of 156 needles tested, 10.9% were positive for HIV antibody. Needle counts on the street showed no significant change in red box areas compared with control areas. In this pilot project, red boxes were accepted by the community and drug users. Police officers also used the boxes to dispose of confiscated needles. Although limited in the number of drop boxes and follow-up time, this pilot project shows promise as a community-based method of safe needle disposal.

Adolescent↗
PubMed1998

Cost and cost-effectiveness of increasing access to sterile syringes and needles as an HIV prevention intervention in the United States.

We determined the cost of increasing access of injection drug users (IDUs) to sterile syringes and needles as an HIV prevention intervention in the United States and the cost per HIV infection averted by such a program. We considered a hypothetical cohort of 1 million active IDUs in the United States. Standard methods were used to estimate the cost and cost-effectiveness of policies to increase access to sterile syringes and syringe disposal at various levels of coverage (e.g., a 100% coverage level would ensure access to a sterile syringe for each injection given current levels of illicit drug injection in the United States; a 50% coverage level would ensure access to one half of the required syringes). A mathematical model of HIV transmission was employed to link programmatic coverage levels with estimates of numbers of HIV infections averted. A policy of funding syringe exchange programs, pharmacy sales, and syringe disposal to cover all illicit drug injections would cost just over $423 million U.S. for 1 year. One third of these costs would be paid for as out-of-pocket expenditures by IDUs purchasing syringes in pharmacies. Compared with the status quo, this policy would cost an estimated $34,278 U.S. per HIV infection averted, a figure well under the estimated lifetime costs of medical care for a person with HIV infection. At very high levels of coverage (>88%), the marginal cost-effectiveness of increased program coverage becomes less favorable. Although the total costs of funding large-scale IDU access to sterile syringes and disposal seem high, the economic benefits are substantial. Even at high levels of coverage, such funding would save society money. As part of a comprehensive program of HIV prevention, policies to increase IDUs access to sterile syringes urgently need further consideration by public health decision makers.

Cost-Benefit Analysis↗
PubMed1998

Tuberculosis risk in funeral home employees.

In order to estimate the risk of tuberculosis infection among employees in the funeral service industry, we conducted a risk-assessment study of a convenience sample of funeral home employees. Study participants completed a risk-assessment questionnaire and underwent tuberculin skin testing. Of 864 employees tested, 101 (11.7%) had a reactive tuberculin skin test. Reactivity to the tuberculin skin test was significantly associated with job category; funeral home employees with a present or past history of embalming deceased-human remains were twice as likely to be reactive as were non-embalming personnel (14.9% versus 7.2%, P < 0.01). Reactivity was also associated with age, gender, race, past history of close contact with a person diagnosed with tuberculosis, and work history. After controlling for age and other factors, tuberculin reactivity was found to be associated in embalming personnel with the number of years spent performing embalmings (> or = 20), and, in non-embalming personnel, with a history of close contact with infected individuals. Based on these results, it is recommended that funeral home employees who routinely embalm cadavers undergo annual tuberculin skin testing, receive initial training on tuberculosis prevention, and wear respiratory protection when preparing known tuberculosis cases.

Adult↗
PubMed1998

Comparison of two measures of human immunodeficiency virus (HIV) type 1 load in HIV risk groups.

Levels of viral burden were compared across risk group and gender populations among 485 human immunodeficiency virus type 1 (HIV-1)-infected participants consisting of 190 male injection drug users (IDUs), 92 female IDUs, and 203 homosexual men. Viral burden was quantified by a microculture technique to determine cell-associated infectious units per 10(6) peripheral blood mononuclear cells (IUPM) and by reverse transcriptase PCR (Amplicor) to determine plasma HIV RNA levels. Adjusting for CD4(+) cell count, females had a lower infectious HIV load than all males combined (0. 33 log10 lower; P = 0.004), and homosexual men had a 0.29 log10 higher infectious viral load than all IDUs combined (P = 0.001). For HIV RNA levels, females had lower levels than males (0.19 log10 lower; P = 0.04), but no differences were observed by risk group. After controlling for percent CD4(+) cells, no differences were found by risk group for either assay, but females still had a 0.25 log10 lower infectious viral load than males (P = 0.04) and a viral RNA load similar to that of males (P = 0.25). The correlation between infectious viral load and HIV RNA load was 0.58 overall, which did not differ by gender or risk group. Our data suggest that differences in viral load may exist by gender and that any differences observed by risk group are driven predominantly by gender or percent CD4(+) cell differences. These data also confirm a moderate correlation between cell-associated infectious viral load and plasma HIV RNA load, which appears to be similar by gender and across risk groups.

Adult↗
PubMed1998

Gender differences in injection-related behaviors among injection drug users in Baltimore, Maryland.

Baseline data from 640 injection drug users in the Stop AIDS for Everyone study, an HIV preventive intervention were used to examine gender differences in self-reports of injection behaviors. In both the bivariate and multivariate analyses men reported injecting alone, in semipublic areas, and at their mother's residence more often than women. In the bivariate analyses, women reported denser personal networks, and in the multivariate analyses, women reported significantly greater overlap between their drug and sex networks. These data suggest that this overlap of sex and drug networks may reduce women drug injectors' ability to adopt and maintain HIV protective behaviors. The data also suggest that interventions need to address gender differences in the social context of risk behaviors.

Adult↗
PubMed1998

The role of needle exchange programs in HIV prevention.

Injecting drug users (IDUs) are at high risk for infection by human immunodeficiency virus (HIV) and other blood-borne pathogens. In the United States, IDUs account for nearly one-third of the cases of acquired immunodeficiency syndrome (AIDS), either directly or indirectly (heterosexual and perinatal cases of AIDS where the source of infection was an IDU). IDU also account for a substantial proportion of cases of hepatitis B (HBV) and hepatitis C (HCV) virus infections. The primary mode of transmission of HIV among IDUs is parenteral, through direct needle sharing or multiperson use of syringes. Despite high levels of knowledge about risk, multiperson use of needles and syringes is due primarily to fear of arrest and incarceration for violation of drug paraphernalia laws and ordinances that prohibit manufacture, sale, distribution, or possession of equipment and materials intended to be used with narcotics. It is estimated that in 1997 there were approximately 110 needle exchange programs (NEPs) in North America. In part, because of the ban on the use of Federal funds for the operation of needle exchange, it has been difficult to evaluate the efficacy of these programs. This chapter presents data from the studies that have evaluated the role of NEPs in HIV prevention. Evidence for the efficacy of NEPs comes from three source: (1) studies originally focused on the effectiveness of NEPs in non-HIV blood-borne infections, (2) mathematical modeling of data on needle exchange on HIV seroincidence, and (3) studies that examine the positive and negative impact of NEPs on HIV and AIDS. Case-control studies have provided powerful data on the positive effect of NEPs on reduction of two blood-borne viral infections (HBV and HCV) For example, a case-control study in Tacoma, Washington, showed that a six-fold increase in HBV and a seven-fold increase in HCV infections in IDUs were associated with nonuse of the NEP. The first federally funded study of needle exchange was an evaluation of the New Haven NEP, which is legally operated by the New Haven Health Department. Rather than relying on self-report of reduced risky injection drug use, this study utilized mathematical and statistical modeling, using data from a syringe tracking and testing system. Incidence of HIV infection among needle exchange participants was estimated to have decreased by 33% as a result of the NEP. A series of Government-commissioned reports have reviewed the data on positive and negative outcomes of NEPs. The major reports are from the National Commission on AIDS; the U.S. General Accounting Office; the Centers for Disease Control/University of California; and the National Academy of Sciences. The latter two reports are used in this chapter. The aggregated results support the positive benefit of NEPs and do not support negative outcomes from NEPs. When legal restrictions on both purchase and possession of syringes are removed, IDUs will change their syringe-sharing behaviors in ways that can reduce HIV transmission. NEPs do not result in increased drug use among participants or the recruitment of first-time drug users.

Case-Control Studies↗
PubMed1998

Satellite exchange in the Baltimore Needle Exchange Program.

OBJECTIVE: Our first objective was to develop an index of satellite exchange and then determine whether satellite exchangers (SEs) differed demographically or behaviorally from other injecting drug users (IDUs). Our second objective was to determine the degree that SEs contributed to needle exchange program (NEP) effectiveness. METHODS: We collected data from approximately 5000 Baltimore Needle Exchange Program (BNEP) participants on the number of syringes acquired and returned over the two-year period February 1995 to February 1997. We then conducted one-way ANOVAs and logistic regressions to determine if SEs were different from other IDUs. RESULTS: We classified 9.35% of the IDUs and SEs and showed that SEs reported levels of drug use and risk behavior similar to other BNEP participants. Although SEs represented less than 10% of all BNEP clients, they accounted for more than 64% of all needles distributed by the BNEP. We showed that SEs accessed more wide-ranging drug use networks than non-SE IDUs and thus can act as potential bridges for human immunodeficiency virus (HIV) prevention materials and messages to larger numbers of drug injectors. CONCLUSIONS: SEs can be expressly targeted with specific prevention messages and encouraged to be "ambassadors" for HIV prevention messages. Efforts to curtail the activities of SEs may detract from the effectiveness of NEPs.

Adult↗
PubMed1998

Drug abuse treatment success among needle exchange participants.

OBJECTIVE: Although lowering incidence rates of human immunodeficiency virus (HIV) transmission is the primary goal of needle exchange programs (NEPs), other desirable outcomes are possible. Referring exchange participants to more comprehensive drug abuse treatment programs has the potential to reduce or eliminate the use of drugs. This possibility was evaluated by comparing the treatment responses of new admissions with an outpatient opioid agonist treatment program in Baltimore, Maryland. METHODS: New admissions (1994 - 1997) to an opioid agonist treatment program were first grouped by referral source (needle exchange, n = 82 vs. standard referrals, n = 243) and then compared on admission demographic and clinical variables and response to treatment during the first three months. Outcome measures included retention rates, self-reported drug use and injecting frequencies, self-reported illegal activities for profit, and results from weekly urinalysis testing for opioids and cocaine. RESULTS: Patients from the NEP were significantly older and more likely to be male, African American, and unemployed than standard referral patients. Needle exchange patients also had a greater baseline severity of drug use than patients in the standard referral group. Despite these baseline differences, both groups achieved comparably good short-term treatment outcomes (including reduced drug use and criminal activity for profit); treatment retention was also good, although slightly better in the standard referral group (88% vs. 76%). CONCLUSION: These data demonstrate the feasibility and merits of creating strong linkages between NEPs and more comprehensive drug abuse treatment clinics.

Adult↗
PubMed1997

Reductions in high-risk drug use behaviors among participants in the Baltimore needle exchange program.

OBJECTIVE: To determine whether enrollment in the Baltimore Needle Exchange Program (NEP) was associated with short-term reduction in risky injection practices. METHODS: Demographic information was collected on NEP participants upon enrollment. A systematic sample of enrollees was interviewed at program entry, 2 weeks, and 6 months later on recent drug-related behaviors. Comparisons were performed using paired t-tests. RESULTS: Among 221 NEP participants who completed baseline, 2-week and 6-month follow-up visits, significant reductions (p < .01) were reported in using a previously used syringe (21.6%, 11.0%, 7.8%, respectively), lending one's used syringe to a friend (26.7%, 18.4%, 12%, respectively), and several indirect sharing activities. Reductions were reported in the mean number of injections per syringe and the mean number of injections per day (p < .001). CONCLUSIONS: These results show rapid and mostly large reductions in a variety of risky injection drug use behaviors. Study findings are consistent with earlier reports showing an association between behavioral risk reduction and participation in a needle exchange program.

Adult↗
PubMed1997

Long-term perspective on the prevalent-cohort biases in studies of human immunodeficiency virus progression.

Because considerable information about progression of human immunodeficiency virus (HIV) infection has been provided by studies of cohorts of individuals with prevalent HIV infection, this study was designed to investigate bias due to onset confounding (differential time-since-infection distributions) and differential length-biased sampling in epidemiologic analyses of data from such cohorts. Subjects were participants in the Italian Seroconverters Study, a seroincident cohort of more than 1,200 adults seen at ambulatory care clinics in Italy, with observed HIV seroconversion in 1980-1988. Acquired immunodeficiency syndrome (AIDS) diagnoses, based on the 1987 Centers for Disease Control case definition, and mortality were ascertained through Italian national registries through 1994. To estimate bias in prevalent cohorts, a series of pseudoseroprevalent (PSP) cohorts were drawn by sampling, from among the total seroincident cohort, prevalent AIDS-free subjects in each calendar year. The relative AIDS risk associated with a given covariate was calculated in each PSP cohort and compared with the relative AIDS risk for that covariate in the seroincident cohort. Relative risks were estimated by both the ratio of AIDS incidence densities and the relative AIDS hazards from proportional hazards regression. Differential length bias was not evident, as assessed in the following way: Among 338 individuals with seroconversion dates in 1983-1986, the relative risk of AIDS for subjects born before 1951 compared with those born more recently was 1.67 (95% confidence interval (CI) 1.30-2.14). Although differential length-biased sampling was expected to bias this relative risk toward 1.0, the observed relative risk for earlier birth ranged from 1.79 to 2.86 in 1987-1992 PSP cohorts. Onset bias was observed: Among 644 subjects with seroconversion in 1980-1988, the AIDS relative risk for 1980-1985 seroconverters compared with 1986-1988 seroconverters was 1.09 (95% CI 0.76-1.55). Onset bias was seen in 1988-1990 PSP cohorts (relative risks for early seroconversion = 1.47, 1.46, and 1.34, respectively); in 1991-1992, relative risks were close to the expected value of 1.09, and CIs on relative risks from all PSP cohorts after 1989 included 1.0. Confounding attributable to differential length-biased sampling in prevalent cohorts does not necessarily bias estimates of the impact of covariates on rate of progression to AIDS. Bias can arise when a covariate suspected of affecting AIDS risk is closely linked to date of acquisition of HIV infection. However, onset bias appears to wane as subjects' dates of infection become more remote.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Design and baseline participant characteristics of the Human Immunodeficiency Virus Epidemiology Research (HER) Study: a prospective cohort study of human immunodeficiency virus infection in US women.

The prospective, multisite human immunodeficiency (HIV) Epidemiology Research Study was established to define the biologic, psychologic, and social effects of HIV infection on the health of US women. From 1993 to 1995, a total of 871 HIV-infected women and 439 demographically matched, uninfected women aged 16-55 years, half of whom reported injection drug use and half of whom reported only sexual risk behaviors, were recruited in four US cities. Two sites recruited primarily from medical/drug therapy care settings, and two recruited from community sources. Women consented to biannual interviews; physical examination; blood, urine, and cervicovaginal specimen collection and repository; laboratory assays; and abstraction of outpatient and inpatient medical records to document HIV and acquired immunodeficiency syndrome-related diagnoses. Retention was greater than 88% at the third 6-month follow-up. Lower retention was associated with currently injecting drugs, not having dependent children, and not being infected with HIV at enrollment. In addition to the core study, a variety of nested studies are under way, some in collaboration with other HIV cohorts and various Public Health Service agencies. This cohort is distinct from other HIV longitudinal cohorts in the diversity of its participants and the comprehensive range of measures to study prospectively the biomedical, social, and emotional effects of the HIV epidemic on infected women and those whose behavior puts them at high risk of infection.

Adolescent↗
PubMed1997

Contrasting genetic influence of CCR2 and CCR5 variants on HIV-1 infection and disease progression. Hemophilia Growth and Development Study (HGDS), Multicenter AIDS Cohort Study (MACS), Multicenter Hemophilia Cohort Study (MHCS), San Francisco City Cohort (SFCC), ALIVE Study.

The critical role of chemokine receptors (CCR5 and CXCR4) in human immunodeficiency virus-type 1 (HIV-1) infection and pathogenesis prompted a search for polymorphisms in other chemokine receptor genes that mediate HIV-1 disease progression. A mutation (CCR2-64I) within the first transmembrane region of the CCR2 chemokine and HIV-1 receptor gene is described that occurred at an allele frequency of 10 to 15 percent among Caucasians and African Americans. Genetic association analysis of five acquired immunodeficiency syndrome (AIDS) cohorts (3003 patients) revealed that although CCR2-64I exerts no influence on the incidence of HIV-1 infection, HIV-1-infected individuals carrying the CCR2-64I allele progressed to AIDS 2 to 4 years later than individuals homozygous for the common allele. Because CCR2-64I occurs invariably on a CCR5-+-bearing chromosomal haplotype, the independent effects of CCR5-Delta32 (which also delays AIDS onset) and CCR2-64I were determined. An estimated 38 to 45 percent of AIDS patients whose disease progresses rapidly (less than 3 years until onset of AIDS symptoms after HIV-1 exposure) can be attributed to their CCR2-+/+ or CCR5-+/+ genotype, whereas the survival of 28 to 29 percent of long-term survivors, who avoid AIDS for 16 years or more, can be explained by a mutant genotype for CCR2 or CCR5.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Postcoital vaginal bleeding as a risk factor for transmission of the human immunodeficiency virus in a heterosexual partner study in Brazil. Rio de Janeiro Heterosexual Study Group.

BACKGROUND: Several risk factors for male-to-female human immunodeficiency virus (HIV) transmission are well established, but few studies have examined the role of postcoital vaginal bleeding. METHODS: Couples recruited from AIDS centers in Rio de Janeiro, Brazil, were interviewed for risk factors and had blood collected for examinations. Eligibility criteria included confirmed HIV positivity for the male partner, aged 18 years of older, heterosexual contact in the past year, and no other risk factor for female partners except sexual contact with the HIV-infected male partner. Logistic regression was used to assess the association between HIV serostatus and risk factors in the female partners. RESULTS: The prevalence of HIV infection was 47.6% among the 418 women available for analysis. The following factors were independently associated with HIV infection; anal sex (odds ratio [OR], 3.06), condom use during vaginal sex sometimes (OR, 1.42) and rarely to never (OR, 2.00) compared with always, frequency of sexual contacts (> 100 in the previous year) (OR, 1.71), HIV-infected male partners with symptoms of acquired immunodeficiency syndrome (OR, 1.70), and postcoital vaginal bleeding (OR, 1.89). The association of postcoital bleeding and HIV infection was more pronounced among women who did not engage in anal sex. CONCLUSIONS: The results support previous studies showing that advanced HIV infection in the male partner, anal sex, inconsistent condom use, and frequent sex are associated with HIV infection among the female partners of HIV-infected men. Postcoital vaginal bleeding was also identified as a risk factor for infection. In addition to other established preventive measures, a recommendation for seeking diagnosis and treatment of sexually transmitted diseases that are associated with postcoital bleeding and using water-soluble lubricants during sex to minimize trauma seems prudent.

Adult↗
PubMed1997

Discarded needles do not increase soon after the opening of a needle exchange program.

This study examines the effect of a Needle Exchange Program (NEP) on the quantity and geographic distribution of discarded needles on the streets of Baltimore, Maryland, and presents methods to survey discarded needles in the community. A random sample of 32 city blocks located within high-drug-use census tracts, stratified by east and west sides of the city and by proximity to the NEP, was selected for survey. Three teams surveyed the number of needles and the number of drug vials and unbroken glass bottles ("trash") to control for practice effects. Surveillance was conducted prior to initiation of the NEP in August 1994 and 1 and 2 months thereafter. Over the three study periods, the absolute count of discarded needles was 106, 130, and 128, respectively; the number of vials and bottles was 3,048, 3,825, and 3,796, respectively. The initial nonstatistically significant increase in needles (mean change = 0.38, 95% confidence interval (CI) -0.18 to 0.93) was offset by accounting for background trash. Regression models fitted with the generalized estimating equation method, which accounted for within-block correlation over time, showed no significant increase in the number of needles after adjustment for trash during the first 2 months of the NEP's operation. These data suggest that the initiation of NEPs does not result in an increase in the number of discarded needles on the street.

Baltimore↗
PubMed1997

Update on the seroepidemiology of human immunodeficiency virus in the United States household population: NHANES III, 1988-1994.

To update the estimate of seroprevalence of HIV from the third National Health and Nutrition Examination Survey (NHANES III), data from the second phase of the survey were combined with previously published data to produce a more precise estimate. The testing was performed anonymously on 11,203 individuals 18-59 years of age examined from 1988 to 1994. Fifty-nine individuals were HIV positive, for an overall prevalence of 0.32%. The number of individuals living in households with HIV infection based on this estimate was 461,000, with a 95% confidence interval of 290,000-733,000. Analysis of nonresponse demonstrated that white and black men 40-59 years of age were least likely to participate in the survey. A sensitivity analysis demonstrated that this nonresponse may have biased the NHANES III estimate downward by 190,000 persons. Data from the second phase of the survey were used to analyze the association between drug use and HIV infection. Black women who used cocaine were 12 times more likely to be HIV positive compared with all tested black women (6.5% vs. 0.55%). This survey provides an estimate of HIV prevalence for individuals who reside in households but excludes some persons who are at higher risk for HIV infection, including prisoners and the homeless not residing in shelters.

Adolescent↗
PubMed1997

Hepatitis A among homosexual men and injection drug users: more evidence for vaccination.

As agencies develop guidelines for administering the newly developed hepatitis A virus (HAV) vaccine, information is needed regarding the occurrence of HAV infection in groups putatively at risk for the infection. We tested serum samples from 300 injection drug users (IDUs), 300 homosexual males, and 300 blood donors for the presence of total antibody to HAV (anti-HAV). Anti-HAV was detected in 66% of IDUs, 32% of homosexual males, and 14% of blood donors. Anti-HAV was not significantly associated (P > .10) with high-risk drug-using behaviors but was more prevalent among IDUs with annual incomes of <$5,000 (P = .018). The occurrence of anti-HAV increased among homosexual males as the number of sexual partners increased (P < .001) but was similar to the age-adjusted prevalence (30.6%) estimated for the general United States population. IDUs are at increased risk for HAV infection; however, our data suggest that factors related to low socioeconomic status contribute more to the occurrence of HAV infection among IDUs than does injection drug use. IDUs and persons at risk for injection drug use should receive HAV vaccine.

Baltimore↗