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Robert S Janssen

Publications and source records attributed to Robert S Janssen.

16 recordsLinked to original sources
PubMed2006

A comprehensive immunization strategy to eliminate transmission of hepatitis B virus infection in the United States: recommendations of the Advisory Committee on Immunization Practices (ACIP) Part II: immunization of adults.

Hepatitis B vaccination is the most effective measure to prevent hepatitis B virus (HBV) infection and its consequences, including cirrhosis of the liver, liver cancer, liver failure, and death. In adults, ongoing HBV transmission occurs primarily among unvaccinated persons with behavioral risks for HBV transmission (e.g., heterosexuals with multiple sex partners, injection-drug users [IDUs], and men who have sex with men [MSM]) and among household contacts and sex partners of persons with chronic HBV infection. This report, the second of a two-part statement from the Advisory Committee on Immunization Practices (ACIP), provides updated recommendations to increase hepatitis B vaccination of adults at risk for HBV infection. The first part of the ACIP statement, which provided recommendations for immunization of infants, children, and adolescents, was published previously (CDC. A comprehensive immunization strategy to eliminate transmission of hepatitis B virus infection in the United States: recommendations of the Advisory Committee on Immunization Practices [ACIP]. Part 1: immunization of infants, children, and adolescents. MMWR 2005;54[No. RR-16]:1-33). In settings in which a high proportion of adults have risks for HBV infection (e.g., sexually transmitted disease/human immunodeficiency virus testing and treatment facilities, drug-abuse treatment and prevention settings, health-care settings targeting services to IDUs, health-care settings targeting services to MSM, and correctional facilities), ACIP recommends universal hepatitis B vaccination for all unvaccinated adults. In other primary care and specialty medical settings in which adults at risk for HBV infection receive care, health-care providers should inform all patients about the health benefits of vaccination, including risks for HBV infection and persons for whom vaccination is recommended, and vaccinate adults who report risks for HBV infection and any adults requesting protection from HBV infection. To promote vaccination in all settings, health-care providers should implement standing orders to identify adults recommended for hepatitis B vaccination and administer vaccination as part of routine clinical services, not require acknowledgment of an HBV infection risk factor for adults to receive vaccine, and use available reimbursement mechanisms to remove financial barriers to hepatitis B vaccination.

Adult↗
PubMed2006

Revised recommendations for HIV testing of adults, adolescents, and pregnant women in health-care settings.

These recommendations for human immunodeficiency virus (HIV) testing are intended for all health-care providers in the public and private sectors, including those working in hospital emergency departments, urgent care clinics, inpatient services, substance abuse treatment clinics, public health clinics, community clinics, correctional health-care facilities, and primary care settings. The recommendations address HIV testing in health-care settings only. They do not modify existing guidelines concerning HIV counseling, testing, and referral for persons at high risk for HIV who seek or receive HIV testing in nonclinical settings (e.g., community-based organizations, outreach settings, or mobile vans). The objectives of these recommendations are to increase HIV screening of patients, including pregnant women, in health-care settings; foster earlier detection of HIV infection; identify and counsel persons with unrecognized HIV infection and link them to clinical and prevention services; and further reduce perinatal transmission of HIV in the United States. These revised recommendations update previous recommendations for HIV testing in health-care settings and for screening of pregnant women (CDC. Recommendations for HIV testing services for inpatients and outpatients in acute-care hospital settings. MMWR 1993;42[No. RR-2]:1-10; CDC. Revised guidelines for HIV counseling, testing, and referral. MMWR 2001;50[No. RR-19]:1-62; and CDC. Revised recommendations for HIV screening of pregnant women. MMWR 2001;50[No. RR-19]:63-85). Major revisions from previously published guidelines are as follows: For patients in all health-care settings HIV screening is recommended for patients in all health-care settings after the patient is notified that testing will be performed unless the patient declines (opt-out screening). Persons at high risk for HIV infection should be screened for HIV at least annually. Separate written consent for HIV testing should not be required; general consent for medical care should be considered sufficient to encompass consent for HIV testing. Prevention counseling should not be required with HIV diagnostic testing or as part of HIV screening programs in health-care settings. For pregnant women HIV screening should be included in the routine panel of prenatal screening tests for all pregnant women. HIV screening is recommended after the patient is notified that testing will be performed unless the patient declines (opt-out screening). Separate written consent for HIV testing should not be required; general consent for medical care should be considered sufficient to encompass consent for HIV testing. Repeat screening in the third trimester is recommended in certain jurisdictions with elevated rates of HIV infection among pregnant women.

AIDS Serodiagnosis↗
PubMed2006

Estimating sexual transmission of HIV from persons aware and unaware that they are infected with the virus in the USA.

BACKGROUND: New HIV infections stem from people who are aware they are HIV positive (approximately 75% of infected persons in the USA) and those who are unaware of their HIV-positive status (approximately 25%). OBJECTIVE: We estimated the relative contribution of these two groups in sexually transmitting new HIV infections to at-risk (HIV-negative or unknown serostatus) partners in the USA. METHODS: The parameters in the estimation included: number of people aware and unaware they are infected with HIV; 33% of the aware group are at low risk of transmitting HIV because of low/undetectable viral load; 57% relative reduction in the prevalence of unprotected anal and vaginal intercourse (UAV) with at-risk partners in persons aware (compared to unaware) they have HIV; and assumed differences in the average number of at-risk UAV partners in each awareness group (ranging from equal to twice as many in the unaware group). RESULTS: The proportion of sexually transmitted HIV from the HIV-positive unaware group was estimated to range from 0.54 (assuming no difference in average number of at-risk UAV partners between groups) to 0.70 (assuming twice as many at-risk UAV partners in the unaware group). Using the lower bounds, the transmission rate from the unaware group was 3.5 times that of the aware group after adjusting for population size differences between groups. CONCLUSION: The results indicate that the HIV/AIDS epidemic can be lessened substantially by increasing the number of HIV-positive persons who are aware of their status.

Female↗
PubMed2006

Recent HIV testing among young men who have sex with men: correlates, contexts, and HIV seroconversion.

OBJECTIVES: We evaluated the correlates and contexts of HIV testing within the past year, subsequent risk reduction, and HIV seroconversion among young men who have sex with men (MSM). METHODS: Young men aged 23 to 29 years were approached, interviewed, counseled, and tested for HIV at 181 randomly sampled MSM-identified venues in six U.S. cities from 1998 through 2000. Analyses were restricted to 2,797 MSM who reported never testing HIV-positive. RESULTS: Of the 2,797 MSM, 1,281 (46%) either never previously tested or had not tested in the past year (never/remote testers); 1,516 (54%) had tested in the past year (recent testers); and 271 (10%) tested HIV-positive as part of the study. Of 1,885 recent sex partners reported by HIV-infected participants, 68% were partners of never/remote testers. Of recent testers, 50% tested anonymously, 51% tested because of specific risks, 59% were counseled, 47% reported reducing their risks after testing, and 8% tested HIV-positive (percent HIV-infected by race: blacks, 24%; Hispanics, 6%; whites, 4%; Asians, 1%). CONCLUSION: Nearly half of young MSM participants had not tested in the past year and HIV-infected never/remote testers accounted for approximately two thirds of recent partners potentially exposed to HIV. Of those who had tested recently, many MSM, especially those who are black, had already acquired HIV. To reduce HIV transmission and facilitate early diagnosis and entry into care, increased HIV testing among young at-risk MSM in the United States, especially those who are black, is needed.

AIDS Serodiagnosis↗
PubMed2005

Meta-analysis of high-risk sexual behavior in persons aware and unaware they are infected with HIV in the United States: implications for HIV prevention programs.

OBJECTIVES: To compare the prevalence of high-risk sexual behaviors in HIV persons aware of their serostatus with that in HIV persons unaware of their status in the United States and to discuss implications for HIV prevention programs. METHODS: A meta-analysis was conducted on 11 independent findings. Six findings compared HIV(+) aware persons with independent groups of HIV(+) unaware persons (between-group comparisons), and 5 findings compared seroconverting individuals before and after being notified of their HIV status (within-subject comparisons). Outcomes were self-reported unprotected anal or vaginal intercourse (UAV) during specified recall periods. RESULTS: The analysis integrating all 11 findings indicated that the prevalence of UAV with any partner was an average of 53% (95% confidence interval [CI]: 45%-60%) lower in HIV persons aware of their status relative to HIV(+) persons unaware of their status. There was a 68% reduction (95% CI: 59%-76%) after adjusting the data of the primary studies to focus on UAV with partners who were not already HIV(+). The reductions were larger in between-group comparisons than in within-subject comparisons. Findings for men and women were highly similar. CONCLUSIONS: The prevalence of high-risk sexual behavior is reduced substantially after people become aware they are HIV(+). Increased emphasis on HIV testing and counseling is needed to reduce exposure to HIV(+) from persons unaware they are infected. Ongoing prevention services are needed for persons who know they are HIV(+) and continue to engage in high-risk behavior.

Adolescent↗
PubMed2005

Unrecognized HIV infection, risk behaviors, and perceptions of risk among young men who have sex with men: opportunities for advancing HIV prevention in the third decade of HIV/AIDS.

This study evaluated the magnitude and distribution of unrecognized HIV infection among young men who have sex with men (MSM) and of those with unrecognized infection, the prevalence and correlates of unprotected anal intercourse (UAI), perceived low risk for infection, and delayed HIV testing. MSM aged 15-29 years were approached, interviewed, counseled, and tested for HIV at 263 randomly sampled venues in 6 US cities from 1994-2000. Of 5649 MSM participants, 573 (10%) tested positive for HIV. Of these, 91% of black, 69% of Hispanic, and 60% of white MSM (77% overall) were unaware of their infection. The 439 MSM with unrecognized infection reported a total of 2253 male sex partners in the previous 6 months; 51% had UAI; 59% perceived that they were at low risk for being infected; and 55% had not tested in the previous year. The HIV epidemic among MSM in the United States continues unabated, in part, because many young HIV-infected MSM are unaware of their infection and unknowingly expose their partners to HIV. To advance HIV prevention in the third decade of HIV/AIDS, prevention programs must reduce unrecognized infection among young MSM by increasing the demand for and availability of HIV testing services.

Acquired Immunodeficiency Syndrome↗
PubMed2003

Performance characteristics of a new less sensitive HIV-1 enzyme immunoassay for use in estimating HIV seroincidence.

Less sensitive (LS) HIV-1 enzyme immunoassays (EIAs) have significantly improved the quantity and quality of HIV surveillance data. The first LS-HIV-1 EIA, the Abbott 3A11-LS, provided reliable incidence data, but the assay required specialized equipment, and the lack of available reagents made testing difficult. This study evaluated the use of an alternate assay, a modified version of the Vironostika HIV-1 EIA (Vironostika-LS), to be used for LS testing. The Vironostika-LS has similar performance characteristics to the Abbott 3A11-LS with additional advantages. This 96-well formatted assay is commonly found in public health laboratories for routine HIV-1 testing and can be used with both serum and dried blood spot specimens. The estimated mean time from seroconversion (defined using a standardized optical density cutoff of 1.0) with the Vironostika-LS was 170 days (95% CI, 145-200 days). When the Vironostika-LS was applied to a matched serum set previously tested with the Abbott 3A11-LS, the Vironostika-LS accurately identified 97% of specimens with recent or long-standing HIV infection. The paper also reports Vironostika-LS quality control guidelines and the results from 3 rounds of proficiency testing.

AIDS Serodiagnosis↗
PubMed2003

Development of a new less-sensitive enzyme immunoassay for detection of early HIV-1 infection.

The sensitive/less-sensitive (S/LS) enzyme immunoassay (EIA) testing strategy for discriminating "early" from "longstanding" HIV infection has been widely applied for detecting recent seroconverters and estimating HIV incidence rates. The originally developed assay (3A11-LS EIA; Abbott Laboratories, Abbott Park, IL) involved performance of LS EIAs using a bead-based assay that required specialized equipment and reagents of limited availability. In contrast, 96-microwell-based EIAs are more universally applied for HIV serodiagnosis throughout the world. The authors report development and preliminary validation of an LS protocol using an EIA in a 96-well format: the Vironostika HIV-1 MicroElisa System (Vironostika-LS EIA; Bio Merieux, Raleigh, NC). The results with samples from recent HIV-1 seroconverters, persons with longstanding HIV-1 asymptomatic infection, patients on highly active antiretroviral therapy, and AIDS patients show a high degree of correlation between the Vironostika-LS EIA and 3A11-LS EIA. The authors also demonstrate that the Abbott 3A11-LS EIA and Vironostika-LS EIA performed comparably on HIV-1-positive samples from persons infected with non-B HIV-1 subtypes. These results support the potential use of the Vironostika-LS EIA for detection of recent HIV-1 infections for incidence projections and for other epidemiologic, clinical, and molecular surveillance applications.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Protease inhibitors and cardiovascular outcomes in patients with HIV-1.

Protease inhibitors for treatment of HIV-1 have been linked with increased risk of hyperlipidaemia and hyperglycaemia. In a cohort of 5672 outpatients with HIV-1 seen at nine US HIV clinics between January, 1993, and January, 2002, the frequency of myocardial infarctions increased after the introduction of protease inhibitors in 1996 (test for trend, p=0.0125). We noted that 19 of 3247 patients taking, but only two of 2425 who did not take, protease inhibitors had a myocardial infarction (odds ratio 7.1, 95% CI 1.6-44.3; Cox proportional hazards model-adjusted for smoking, sex, age, diabetes, hyperlipidaemia, and hypertension-hazard ratio 6.5, 0.9-47.8). Our findings suggest that, although infrequent, use of protease inhibitors is associated with increased risk of myocardial infarction in patients with HIV-1.

Adult↗
PubMed2002

HIV seroincidence among patients at clinics for sexually transmitted diseases in nine cities in the United States.

Although the numbers of newly reported diagnoses of AIDS decreased in the 1990s, it is not clear whether they reflect a decreasing number of new HIV infections. Direct measurement of HIV incidence through follow-up cohort studies is difficult and costly. We estimated HIV incidence and trends in incidence among men who have sex with men (MSM) and heterosexual men and women at clinics for sexually transmitted diseases (STDs) by using a recently developed serologic testing algorithm that requires only a single blood specimen. Cross-sectional anonymous serosurveys were conducted at 13 STD clinics in nine cities in the United States from 1991 through 1997. Before anonymous HIV testing, demographic and clinical information was abstracted. Of 129,774 specimens tested, 362 (0.28%) were from persons estimated to be recently infected. Incidence among MSM was 7.1% (95% confidence interval (CI): 4.8-10.3), 14 times higher than that among heterosexuals, which was 0.5% (CI: 0.4- 0.7). Incidence among MSM and heterosexuals remained unchanged during the time studied. Decreasing rates of new AIDS diagnoses in the 1990s do not reflect stable rates of new HIV infections among MSM and heterosexual patients attending these clinics.

Adult↗
PubMed2002

Repeat HIV testing, risk behaviors, and HIV seroconversion among young men who have sex with men: a call to monitor and improve the practice of prevention.

OBJECTIVES: We compared recent risk behaviors and HIV seroconversion among young men who have sex with men (MSM) who were first-time, infrequent, and repeat HIV testers. METHODS: Male adolescents and young men aged 15 to 22 years were randomly sampled, interviewed, counseled, and tested for HIV at 194 gay-identified venues in seven U.S. cities from 1994 through 1998. Analyses were restricted to MSM who reported having never tested or last tested HIV-negative. RESULTS: Of 3430 participants, 36% tested for the first time, 39% had tested infrequently (one or two times), and 26% had tested repeatedly (> or = three times). Compared with first-time testers, repeat testers were more likely to report recent risk behaviors and to acquire HIV (7% versus 4%). Over 75% of repeat testers who seroconverted acquired HIV within 1 year of their last test. Compared with repeat testers, first-time testers reported similar use of health care but delayed testing for nearly 2 additional years after initiating risk. CONCLUSIONS: Many young MSM soon acquire HIV after repeated use of HIV counseling and testing services. Providers must strengthen practices to identify, counsel, and test young MSM and provide enhanced behavioral interventions for those with persistent risks.

Adolescent↗
PubMedDate not supplied

Classification of transmission risk in the national HIV/AIDS surveillance system.

Risk behavior information is essential for allocating resources and developing effective HIV prevention strategies. Over time, transmission risk information on HIV/AIDS cases has been less likely to be reported to the national surveillance system. The Centers for Disease Control and Prevention (CDC) invited approximately 30 experts in HIV/AIDS and behavioral research from state and local health departments, academia, community-based organizations, and the CDC to participate in a consultation in December 2001 to generate ideas on how best to deal with the lack of risk data. The group was charged with providing recommendations on methods for classifying and reporting risk information and for identifying methods and sources for improving ascertainment of transmission risk behaviors for individuals infected with HIV. This report describes the recommendations and the effects of implementing such recommended procedures on the national HIV/AIDS surveillance database.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Aligning budget with U.S. National HIV prevention priorities.

Reducing new HIV infections in the United States requires allocating public resources to interventions that will have the greatest impact on reducing the number of new infections. We report on the organizational experience of a federal agency's efforts to align its HIV prevention resources to reflect the specific priorities of a five-year strategic plan that has as its goal a fifty percent reduction in the number of annual HIV infections nationwide. Structural and other impediments encountered during the alignment process, and the steps taken to minimize their impact are described, adding to the empirical data base of strategic planning experiences in the public sector.

Budgets↗
PubMedDate not supplied

CDC: HIV prevention efforts.

Explore the source record for details and available documents.

Centers for Disease Control and Prevention, U.S.↗