Myron S. Cohen

Bio: Myron S. Cohen is an academic researcher from University of North Carolina at Chapel Hill. The author has contributed to research in topics: Population & Acquired immunodeficiency syndrome (AIDS). The author has an hindex of 103, co-authored 549 publications receiving 46021 citations. Previous affiliations of Myron S. Cohen include University of Massachusetts Medical School & Scripps Health.

Evaluation of azithromycin resistance in Treponema pallidum specimens from madagascar

Abstract: Treponema pallidum resistance to azithromycin has been documented in the US, Canada, and Ireland. We found no evidence of resistance to azithromycin in specimens from 141 patients with syphilitic lesions in Madagascar suggesting resistance is geographically isolated and supporting use of azithromycin as alternative treatment for early syphilis in Madagascar.

Continued high risk sexual behavior following diagnosis with acute HIV infection in South Africa and Malawi: implications for prevention.

Abstract: Understanding sexual behavior following diagnosis of acute HIV infection (AHI) is key to developing prevention programs targeting individuals diagnosed with AHI. We conducted separate qualitative and quantitative interviews with individuals newly diagnosed (n = 19) with AHI at 1-, 4- and 12-weeks post-diagnosis and one qualitative interview with individuals who had previously been diagnosed with AHI (n = 18) in Lilongwe, Malawi and Johannesburg, South Africa between October 2007 and June 2008. The majority of participants reported engaging in sexual activity following diagnosis with AHI with a significant minority reporting unprotected sex during this time. Most participants perceived to have changed their behavior following diagnosis. However, participants reported barriers to condom use and abstinence, in particular, long term relationships and the need for disclosure of sero-status. Understanding of increased infectiousness during AHI was limited. Participants reported a desire for a behavioral intervention at the time of AHI diagnosis, however, there were differences by country in the types of interventions participants found acceptable. Studies are underway to determine the feasibility, acceptability and potential effectiveness of interventions designed for individuals with AHI.

Protease inhibitor and nonnucleoside reverse transcriptase inhibitor concentrations in the genital tract of HIV-1-infected women.

Abstract: The pharmacokinetics of antiretrovirals (ARVs) in the female genital tract (FGT) are likely to influence vertical and sexual transmission of HIV, the development of viral resistance, and post-exposure prophylaxis regimens. This study is the first to compare ARV concentrations in direct aspirates of cervicovaginal fluid (CVF) and blood plasma (BP). This unique method provides direct assessment of concentrations without the confounding of cervicovaginal lavage dilution. Of 8 ARVs, CVF concentrations ranged from 100% of BP concentrations. These large differences in CVF penetration suggest that further research into ARV pharmacokinetics and drug efficacy in the FGT is necessary.

Effects of reverse transcriptase inhibitor therapy on the HIV-1 viral burden in semen.

Abstract: HIV-1 infection continues to spread worldwide, primarily through sexual intercourse. Because semen is a major vehicle for transmission of HIV-1, we evaluated the effects of reverse transcriptase inhibitor therapy on the amount of HIV-1 in semen. The semen and blood of 11 HIV-1-infected men (i.e. treatment group) were collected before the initiation of reverse transcriptase inhibitor therapy and then 8 to 18 weeks after initiation of therapy. The semen and blood of another 11 HIV-1-infected men (i.e., longitudinal group), who were not on or had no change in antiretroviral therapy for at least 2 months before study entry, were collected at approximately 2-week intervals for 10 to 26 weeks. In the treatment group, 82% of the seminal plasma HIV-1 RNA levels decreased from baseline after 8 to 18 weeks of therapy (median reduction of 1.01 log10, p = 0.01), and 100% of the blood plasma RNA levels decreased from baseline over the same period (median reduction of 0.92 log10, p = 0.003). Five of these patients were followed for at least 52 weeks and had a median seminal plasma HIV-1 RNA level of 0.66 log10 below baseline at 1 year. All subjects in the treatment group with positive cultures at baseline (50%) had negative cultures or a lower infectious units per ejaculate at the 8- to 18-week follow-up examinations. The HIV-1 RNA levels in blood and semen of the longitudinal group did not change significantly over 10 to 26 weeks. Initiation of reverse transcriptase inhibitor therapy effectively reduces shedding of HIV-1 in semen and may therefore reduce the spread of infection within populations.

Combination prevention for COVID-19.

Abstract: The coronavirus disease 2019 (COVID-19) pandemic has produced the fear and disorder inevitably provoked by emerging pathogens. As such, it should also inspire consideration of our experience with HIV over the past 40 years. As with HIV, the road to reducing infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, the cause of COVID-19), and attendant morbidity and mortality, requires medical and nonmedical strategies. The most important lesson learned from tackling HIV is to use a combination of prevention strategies. The first step to stopping the spread of SARS-CoV-2 has already been taken—behavioral changes. This reflects a rapid but imperfect understanding of the transmission of this virus. At the beginning of the AIDS epidemic, changes in sexual behavior, condom promotion, and government interventions (closing “hotspots” of HIV transmission such as bathhouses) made a difference. For SARS-CoV-2, masks and gloves, hand hygiene, and “shelter in place” mandates have already demonstrated benefits. More efficient behavioral intervention requires better understanding of the rules governing SARS-CoV-2 transmission. What are the risks from exposure to respiratory droplets, airborne virus, and surface contamination? What concentration of SARS-CoV-2 is required for transmission? Evidence suggests that SARS-CoV-2 transmission is greatest very early in infection prior to development of symptoms—the same lessons learned from HIV. Given this rule of transmission, biomedical prevention strategies that provide reliable protection become essential. And as has proven true for HIV, directing prevention to people at the highest risk for SARS-CoV-2 infection or the worst disease outcomes will be an important consideration. Historically, antiviral therapies that reduce the severity of infection have preceded the development of biomedical approaches to prevent onward transmission (although interruption of viral replication also offers a prevention benefit). The first HIV treatment, azidothymidine (AZT), extended life by up to 18 months, providing hope that HIV infection could be transformed from a death sentence to a treatable disease. Reduced risk of mother-to-child transmission by AZT was the first biomedical prevention against HIV transmission. This success was the precursor to “pre-exposure prophylaxis.” AZT also launched research focused on “treatment as prevention” where antiviral agents reduce the HIV viral load to a point where infected people no longer transmit. This approach, which uses combinations of powerful antiretroviral agents, is now the mainstay of HIV prevention worldwide. For SARS-CoV-2, we have leapt into a cacophony of clinical trials of drug candidates with differing degrees of plausibility. Preliminary results from a large randomized controlled trial show that the antiviral drug remdesivir substantially reduced the duration of hospitalization for COVID-19. To date, COVID-19 testing results have been used primarily for patient isolation, contact tracing, and quarantine. But effective therapies will lend great urgency for the universal availability of rapid and reliable testing for SARS-CoV-2 infection, so that treatment can be provided when indicated. Long-acting antiviral agents and monoclonal antibodies that neutralize SARS-CoV-2 may become important nonvaccine pharmacologic tools for prevention. Antiviral agents that prevent replication of SARS-CoV-2 could be used as pre-, peri-, or postexposure prophylaxis. Several different potent monoclonal antibody combinations designed to treat and prevent SARS-CoV-2 will enter clinical trials in June 2020. Ultimately, a safe and effective vaccine is crucial for preventing COVID-19. Vaccine efforts started immediately after the discovery of SARS-CoV-2. Numerous vaccine candidates have been identified, and early-phase vaccine studies of several are underway. Proof of vaccine efficacy will require large trials with 6000 to 12,000 participants or more in each study. Because SARS-CoV-2 is moving around the planet, clinical research teams must prepare for trials where incident infections occur (a sufficient “attack rate”). We cannot predict the time of availability or degree of efficacy of a SARS-CoV-2 vaccine with precision, but most trials in development are designed to demonstrate 60 or 70% prevention efficacy, not 100% protection. HIV has taught us that multiple concomitant prevention strategies are essential. Behavioral changes to reduce SARS-CoV-2 spread must be accepted as the “new normal.” The COVID-19 toolbox must include safe and effective interventions whose values have been proven through robust scientific methods honed over decades. Ongoing research in each prevention domain must be sustained. We simply cannot depend on any single “magic bullet.”

Prevention of HIV-1 Infection with Early Antiretroviral Therapy

Abstract: Background Antiretroviral therapy that reduces viral replication could limit the transmission of human immunodeficiency virus type 1 (HIV-1) in serodiscordant couples. Methods In nine countries, we...

Infectious Diseases Society of America/American Thoracic Society Consensus Guidelines on the Management of Community-Acquired Pneumonia in Adults

Abstract: Lionel A. Mandell, Richard G. Wunderink, Antonio Anzueto, John G. Bartlett, G. Douglas Campbell, Nathan C. Dean, Scott F. Dowell, Thomas M. File, Jr. Daniel M. Musher, Michael S. Niederman, Antonio Torres, and Cynthia G. Whitney McMaster University Medical School, Hamilton, Ontario, Canada; Northwestern University Feinberg School of Medicine, Chicago, Illinois; University of Texas Health Science Center and South Texas Veterans Health Care System, San Antonio, and Michael E. DeBakey Veterans Affairs Medical Center and Baylor College of Medicine, Houston, Texas; Johns Hopkins University School of Medicine, Baltimore, Maryland; Division of Pulmonary, Critical Care, and Sleep Medicine, University of Mississippi School of Medicine, Jackson; Division of Pulmonary and Critical Care Medicine, LDS Hospital, and University of Utah, Salt Lake City, Utah; Centers for Disease Control and Prevention, Atlanta, Georgia; Northeastern Ohio Universities College of Medicine, Rootstown, and Summa Health System, Akron, Ohio; State University of New York at Stony Brook, Stony Brook, and Department of Medicine, Winthrop University Hospital, Mineola, New York; and Cap de Servei de Pneumologia i Allergia Respiratoria, Institut Clinic del Torax, Hospital Clinic de Barcelona, Facultat de Medicina, Universitat de Barcelona, Institut d’Investigacions Biomediques August Pi i Sunyer, CIBER CB06/06/0028, Barcelona, Spain.

Role of free radicals and catalytic metal ions in human disease: an overview.

Abstract: Publisher Summary This chapter discusses the role of free radicals and catalytic metal ions in human disease. The importance of transition metal ions in mediating oxidant damage naturally leads to the question as to what forms of such ions might be available to catalyze radical reactions in vivo . The chapter discusses the metabolism of transition metals, such as iron and copper. It also discusses the chelation therapy that is an approach to site-specific antioxidant protection. The detection and measurement of lipid peroxidation is the evidence most frequently cited to support the involvement of free radical reactions in toxicology and in human disease. A wide range of techniques is available to measure the rate of this process, but none is applicable to all circumstances. The two most popular are the measurement of diene conjugation and the thiobarbituric acid (TBA) test, but they are both subject to pitfalls, especially when applied to human samples. The chapter also discusses the essential principles of the peroxidation process. When discussing lipid peroxidation, it is essential to use clear terminology for the sequence of events involved; an imprecise use of terms such as initiation has caused considerable confusion in the literature. In a completely peroxide-free lipid system, first chain initiation of a peroxidation sequence in a membrane or polyunsaturated fatty acid refers to the attack of any species that has sufficient reactivity to abstract a hydrogen atom from a methylene group.

Regression Diagnostics: Identifying Influential Data and Sources of Collinearity

Abstract: 1. Introduction and Overview. 2. Detecting Influential Observations and Outliers. 3. Detecting and Assessing Collinearity. 4. Applications and Remedies. 5. Research Issues and Directions for Extensions. Bibliography. Author Index. Subject Index.

Sexually transmitted diseases treatment guidelines.

Abstract: The MMWR series of publications is published by the Office of Surveillance, Epidemiology, and Laboratory Services, Centers for Disease Control and Prevention (CDC), U.S. Department of Health and Human Services, Atlanta, GA 30333.