Edgar Monterroso

Prevalence and incidence of hepatitis C virus infection among young adult injection drug users

Through community-based outreach, young adult injection drug users (IDUs) were enrolled in a prospective study of the prevalence, incidence, and risk factors for hepatitis C virus (HCV) infection. Demographics and information on sexual and injecting practices were collected during semiannual interviews, and HCV infection was evaluated using a second-generation antibody assay. Of the 229 participants, 86 (37.6%) were HCV-seropositive at baseline. After adjusting for injecting frequency and duration by logistic regression, HCV seroprevalence was independently associated with reusing syringes at least once in the past 6 months (odds ratio [OR]=3.81, 95% confidence interval [CI] 1.39-11.00), injecting the first time with someone > or =5 years older (OR=2.99; 95% CI, 1.43-6.23) or alone (OR=4.02; 95% CI, 1.12-14.43) versus with someone <5 years older, and injecting cocaine or speedball exclusively (OR=4.29; 95% CI, 1.53-12.01) or with other drugs (OR=5.27; 95% CI, 2.62-10.64) versus injecting no cocaine in the past 6 months. Of the 105 originally HCV-seronegative participants who returned for follow-up, 13 seroconverted (incidence rate=16.0/100 person-years). On bivariate analysis, HCV seroconversion was significantly associated with injecting for <2 years (relative risk [RR]=7.3; 95% CI, 1.6-32.8) and continuing to inject during follow-up (RR=4.4; 95% CI, 1.0-19.9). Young adult IDUs are at high risk for HCV infection. These data support the need for wider legal access to sterile syringes, as well as expanded community outreach education to this population to prevent transmission of HCV.

Hepatitis C Virus Infection: Prevalence, Risk Factors, and Prevention Opportunities among Young Injection Drug Users in Chicago, 1997–1999

The prevalence, risk factors, and prevention opportunities of hepatitis C virus (HCV) infection were studied in a large sample of 698 young adult injection drug users (IDUs) in Chicago, 18-30 years old. Participants were recruited between 1997 and 1999 by using street outreach, targeted advertising, and chain-referral methods. HCV infection prevalence was 27% and was strongly associated with both age and duration of injecting (P<.001). In multivariable analysis, sexual behaviors were unrelated to seropositivity. Independent drug-related risk factors included frequent injection, heavy crack smoking, injecting in a shooting gallery, and syringe-mediated sharing. Urban residents were more likely than suburban residents to be infected. Most research on hepatitis C has shown rapid spread of infection among IDUs, but these findings underscore that opportunities to identify IDUs uninfected with HCV may be greater than assumed and emphasize the need to target younger, newer IDUs.

Declining seroprevalence in a very large HIV epidemic: injecting drug users in New York City, 1991 to 1996.

OBJECTIVES This study assessed recent trends in HIV seroprevalence among injecting drug users in New York City. METHODS We analyzed temporal trends in HIV seroprevalence from 1991 through 1996 in 5 studies of injecting drug users recruited from a detoxification program, a methadone maintenance program, research storefronts in the Lower East Side and Harlem areas, and a citywide network of sexually transmitted disease clinics. A total of 11,334 serum samples were tested. RESULTS From 1991 through 1996, HIV seroprevalence declined substantially among subjects in all 5 studies: from 53% to 36% in the detoxification program, from 45% to 29% in the methadone program, from 44% to 22% at the Lower East Side storefront, from 48% to 21% at the Harlem storefront, and from 30% to 21% in the sexually transmitted disease clinics (all P < .002 by chi 2 tests for trend). CONCLUSIONS The reductions in HIV seroprevalence seen among injecting drug users in New York City from 1991 through 1996 indicate a new phase in this large HIV epidemic. Potential explanatory factors include the loss of HIV-seropositive individuals through disability and death and lower rates of risk behavior leading to low HIV incidence.

Risk behavior and HIV infection among new drug injectors in the Era of AIDS in New York City

OBJECTIVE To examine HIV risk behavior and HIV infection among new initiates into illicit drug injection in New York City. DESIGN AND METHODS Cross-sectional surveys of injecting drug users (IDUs) recruited from a large detoxification treatment program (n=2489) and a street store-front research site (n=2630) in New York City from 1990 through 1996. Interviews covering demographics, drug use history, and HIV risk behavior were administered; serum samples were collected for HIV testing. Subjects were categorized into two groups of newer injectors: very recent initiates (just began injecting through 3 years) and recent initiates (injecting 4-6 years); and long-term injectors (injecting > or = 7 years). RESULTS 954 of 5119 (19%) of the study subjects were newer injectors, essentially all of whom had begun injecting after knowledge about AIDS was widespread among IDUs in the city. New injectors were more likely to be female and white than long-term injectors, and new injectors were more likely to have begun injecting at an older age (median age at first injection for very recent initiates, 27 years; median age at first injection for recent initiates, 25 years; compared with median age at first injection for long-term injectors, 17 years). The newer injectors generally matched the long-term injectors in frequencies of HIV risk behavior; no significant differences were found among these groups on four measures of injection risk behavior. HIV infection was substantial among the newer injectors: HIV prevalence was 11% among the very recent initiates and 18% among the recent initiates. Among the new injectors, African Americans, Hispanics, females, and men who engaged in male-male sex were more likely to be infected. CONCLUSIONS The new injectors appear to have adopted the reduced risk injection practices of long-term injectors in the city. HIV infection among new injectors, however, must still be considered a considerable public health problem in New York City.

Gender differences in the initiation of injection drug use among young adults

To characterize the circumstances surrounding initiation of injecting drug use, data were collected from 229 young, recently initiated injection drug users enrolled through community-based recruitment in Baltimore, Maryland. Gender differences in the pattern of initiation, the number of persons present at initiation, risky injection, and sexual behaviors at initiation, as well as behaviors after initiation, were examined. Overall, men and women were similar statistically with respect to age at initiation (19.5 years) and risk behaviors at initiation. While men were initiated by men (77%), women were more often initiated by women (65%), most of whom were friends (75%) or relatives (23%). The percentage of women infected with human immunodeficiency virus (HIV) was slightly greater than that of men, 17% versus 11% (P<.2), whether initiated by a man or a woman. Persons who self-initiated had a lower HIV prevalence and fewer HIV-related risk behaviors. Analysis of variance assessed differences in the HIV risk profiles of female and male IDUs who were intiated by someone of the same sex, of the opposite sex, or who self-initiated. These results indicated that (1) young women and men had similar patterns of injection initiation; (2) most women were initiated by female friends, runing counter to earlier literature claims that women were initated to injection drug use by male sex partners; and (3) women initiated by men had a marginally greater mean score on the HIV risk profile.

Prevention of HIV Infection in Street-Recruited Injection Drug Users

Background: Injection drug users (IDUs) and their sex partners account for an increasing proportion of new AIDS and HIV cases in the United States, but public debate and policy regarding the effectiveness of various HIV prevention programs for them must cite data from other countries, from non‐street‐recruited IDUs already in treatment, or other programs, and from infection rates for pathogens other than HIV. Methods: Participants were recruited from the street at six sites (Baltimore [Maryland], New York [two sites], Chicago [Illinois], San Jose [California], Los Angeles [California], and at a state womens correctional facility [Connecticut]), interviewed with a standard questionnaire, and located and reinterviewed at one or more follow‐up visits (mean, 7.8 months later). HIV serostatus and participation in various programs and behaviors that could reduce HIV infection risk were determined at each visit. Results: In all, 3773 participants were recruited from the street, and 2306 (61%) were located and interviewed subsequently. Of 3562 initial serum specimens, 520 (14.6%) were HIV‐seropositive; at subsequent assessment, 19 people, all from the East Coast and Chicago, had acquired HIV. Not using previously used needles was substantially protective against HIV acquisition (relative risk [RR], 0.29; 95% confidence interval [CI], 0.11‐0.80 ) and, in a multivariate model, was significantly associated with use of needle and syringe exchange programs (adjusted odds ratio [ORadj], 2.08; 95% CI, 1.15‐3.85). Similarly, reduction of injection frequency was very protective against seroconversion (RR, 0.33; 95% CI, 0.14‐0.80), and this behavior was strongly associated with participation in drug treatment programs (ORadj, 3.54; 95% CI, 2.50‐5.00). In a separate analysis, only 37.5% of study‐participants had sufficient new needles to meet their monthly demand. Conclusions: In this large multicity study of IDUs in the United States, several HIV prevention strategies appeared to be individually and partially effective; these results indicate the continued need for, and substantial gaps in, effective approaches to preventing HIV infection in drug users.

Injection-related risk behaviors in young urban and suburban injection drug users in Chicago (1997-1999).

Summary: We compared injection‐related risk practices between urban and suburban injection drug users (IDUs) in a large cross‐sectional sample of young IDUs. From 1997 to 1999, we recruited 700 active IDUs aged 18 to 30 years in Chicago and its suburbs. A suburban residence was reported by 38% of participants. Participants were interviewed at four urban locations and screened for HIV and hepatitis C virus antibodies. Receptive sharing of syringes and other paraphernalia by urban and suburban IDUs in the preceding 6 months was compared using univariable and multivariable models. Sharing injection paraphernalia in the total sample was high, with 50% of participants reporting receptive syringe sharing and 70% reporting sharing cotton, cookers, and/or rinse water. After adjusting for demographic characteristics, injection settings, frequency, and duration of injection as well as ease of acquiring new syringes, suburban IDUs were significantly more likely than urban IDUs to share syringes (adjusted odds ratio = 1.7; 95% confidence interval: 1.1‐2.5); however, the likelihood of sharing cotton, cookers, or rinse water was roughly equal. Despite overall higher risk profiles among suburban IDUs, HIV and hepatitis C prevalence levels were significantly lower than among urban participants. Current high levels of injection risk behaviors in suburban groups represent a potential for rapid dissemination of infection.

Sex-Specific Differences in Circumstances of Initiation into Injecting-Drug Use Among Young Adult Latinos in Harlem, New York City

Background: Data are limited that examine circumstances of initiation and risk for HIV infection among Latino injecting-drug users (IDUs) in the United States. Methods: Baseline data were obtained from a cohort study of young (aged 18–29 years) IDUs residing in Harlem, New York City, conducted during 1997–1999. Participants were administered standardized face-to-face interviews. Data collected included demographics, age and circumstances surrounding initiation of injecting-drug use, and lifetime and recent risk behaviors. Results: Of the 156 participants who self-identified as Latino, 145 (94%) were Puerto Rican, 112 (72%) were male, and 44 (28%) were female. The median number of years of injecting drug use was 3 for women and 5 for men (Wilcoxon ranks sums test p = .007). Significantly (p < .05) more women than men reported that at the first injection episode, they were injected by a sexual partner (26% versus 4%), were provided the syringe by their sexual partner (24% versus 4%), had sex with the initiator after being injected the first time (23% versus 5%), and were injected by a person ≥5 years older than themselves (50% versus 32%). Women were more likely than men to report having ever had unprotected sex with a person known to be HIV-positive (18% versus 4%, respectively; p = .006); however, women were just as likely as men to report having ever injected drugs with a person known to be HIV-positive (11% versus 10%). Conclusions: Latinas were more likely than their male counterparts to be initiated either directly (being injected) or indirectly (being provided a syringe) into injecting-drug use by their sexual partner. HIV and drug use prevention programs for Latinas in Harlem must address the interrelationship between drug use and sexual relations.

High Rates of STD and Sexual Risk Behaviors Among Garífunas in Honduras

Background: Honduras has the highest concentration of HIV and AIDS cases in Central America, with an estimated adult HIV prevalence of 1.5%. Prevalence is higher among certain ethnic groups such as the Garífuna with a reported HIV prevalence of 8%. Methods: A biological and behavioral survey was conducted on a stratified random sample of the Garífuna population in Honduras, using computer-assisted interviews. Blood was tested for HIV, herpes simplex type 2 (HSV-2), and syphilis; urine was tested for Chlamydia trachomatis, Neisseria gonorrhoea, Trichomonas vaginalis, and Mycoplasma genitalum. Results: We enrolled a total of 817 participants, 41% female and 51% male. Estimated prevalences and 95% confidence intervals (CI) were: HIV, 4.5% (95% CI: 3.0 to 6.6), HSV-2, 51.1% (95% CI: 46.7 to 55.6), and syphilis seropositivity, 2.4% (95% CI: 1.4 to 4.0). Sexually transmitted infections in urine were: chlamydia, 6.8% (95% CI: 4.7 to 9.7), gonorrhea, 1.1% (95% CI: 0.4 to 2.9), trichomoniasis, 10.5% (95% CI: 8.1 to 13.6), and Mycoplasma genitalium, 7.1% (95% CI: 5.1 to 9.9). Consistent condom use was low with stable (10.6%) and casual (41.4%) partners. In multivariate analysis, HIV was associated with rural residence. HSV-2 was associated with female sex, older age, and syphilis seropositivity. Conclusions: We found a moderate prevalence of HIV and a high prevalence of HSV-2 among the Garífunas. HSV-2 may increase the vulnerability of these populations to HIV in the future. Intervention strategies should emphasize sexually transmitted infection control and condom promotion, specifically targeting the Garífuna population.

Predictors of syphilis seroreactivity and prevalence of HIV among street recruited injection drug users in Los Angeles County, 1994–6

Objectives: To describe HIV prevalence and the association between syphilis incidence and sexual and drug injection risk behaviours in a cohort of street recruited injecting drug users (IDUs) in Los Angeles County, between 1994 and 1996. Methods: During the study period, 513 street recruited African-American and Latino IDUs were screened for syphilis and antibodies to HIV. Subjects were administered a risk behaviour survey at baseline and followed up at 6 month intervals for 18 months with repeated interviews and serological screening. Rate ratios were used to examine associations between syphilis incidence and demographic characteristics and risk behaviours. A proportional hazard model was used to identify predictors of syphilis incidence independent of demographic characteristics. Results: 74% of the sample were male, 70% African-American, 30% Latino; and the median age was 43 years. Overall baseline serological prevalence of HIV was 2.5% and of syphilis 5.7%. None of the participants were co-infected for HIV and syphilis at baseline or at any of the 6 month follow ups. Among 390 eligible IDUs retained for analysis of incidence data, the overall syphilis incidence was 26.0 per 1000 person years. Higher syphilis incidence was found for women compared with men (RR=2.70; 95% CI 1.60, 4.55), and for those 44 years of age or younger compared with those 45 years of age and older (RR=2.26; 95% CI 1.25, 4.08). African-Americans were more likely to be syphilis incident cases when compared with Latinos, although the difference did not reach statistical significance (RR=1.27; 95% CI 0.72, 2.23). In bivariate analysis, risk behaviours significantly associated with higher syphilis incidence included injection of cocaine, “speedball” and heroin, “crack” smoking, recency of first injection event, backloading of syringes, injecting with others, exchanging drugs or money for sex, multiple sex partners, and non-heterosexual sexual preference. Variables that significantly predicted syphilis infection at follow up in the multivariate analysis included multiple sex partners (RR=7.8; 95% CI 2.4, 25.0), exchanging money for sex (RR=3.0; 95% CI 0.9, 9.6), and recent initiation to injection drug use (RR=4.6; 95% CI 1.1, 18.8). Conclusion: Syphilis transmission among IDUs in Los Angeles County remains a serious public health concern, particularly among IDUs who engage in trading of sex for money or drugs. Although low, the prevalence of HIV observed in this study constitutes a serious concern because of the potential for expanded HIV transmission in this susceptible population of IDUs with high syphilis incidence. Enhanced case finding screening efforts and prevention of transmission of sexually transmitted infections should specifically target hard to reach IDUs and their sexual partners.