CROI 2017 Abstract e-Book

Abstract eBook

Oral Abstracts

strategies have to be assessed. The success of PrEP for HIV has raised interest in biomedical interventions for STIs. Pending the development of vaccines against bacterial STIs, the potential role of antibiotic prophylaxis should be re-assessed. Early studies conducted by the military have shown the short-term efficacy and the limitations of post-exposure prophylaxis. More recently, periodic presumptive treatment in female sex workers with azithromycin alone or in combination have shown reduction in incidence of gonorrhea and chlamydia but not of syphilis or HIV. Mass treatment with azithromycin for trachoma and Yaws elimination has also shown some impact on STIs prevalence. Studies using doxycycline prophylaxis for syphilis in high risk MSM are ongoing. Such studies in selected populations should be conducted cautiously and involvement of these populations in the design, implementation and evaluation of these new interventions is crucial. Should antibiotic prophylaxis be successful at reducing STIs incidence, its short-term benefits should be balanced against the long-term efficacy of this strategy, its tolerability, cost, and more importantly the selection and dissemination of antibiotic resistance when drug resistance to gonorrhea is already a threat and only limited options are available for treatment of chlamydia infection and syphilis. Also, antibiotic prophylaxis might alter STIs presentation and lead to an increase in STIs not targeted by the prophylaxis, underscoring the need for this strategy to be included in a comprehensive prevention package with a close monitoring of all STIs. Conclusion: New strategies need to be developed to contain the spread of STIs. Antibiotic prophylaxis for bacterial STIs in high risk populations should be carefully evaluated. 56 SYPHILIS IN THE ERA OF TREATMENT AS PREVENTION AND PRE-EXPOSURE PROPHYLAXIS Matthew R. Golden, Univ of Washington, Seattle, WA, USA Rates of syphilis in most high income nations have been steadily increasing since 2000, but that increase has accelerated since 2010, rising 56-130% over the last 5 years in the US, U.K. Germany, France, and Australia. In all of these areas, syphilis predominately affects men who have sex with men (MSM), particularly HIV-infected MSM. However, some evidence suggests that the syphilis epidemic is now expanding to include HIV-negative MSMwithout risk factors such as methamphetamine use, and in some areas, rates are now rising among women, with an associated risk of increasing congenital syphilis. Factors contributing to the rise in syphilis include the integrated effects of widespread and effective HIV treatment, HIV pre-exposure prophylaxis (PrEP), and geosocial apps, which together facilitate condomless sex guided by diverse seroadaptive behaviors. The rise of syphilis poses challenges for clinicians as they confront increasing numbers of cases of neuro-, ocular- and otosyphilis, and dilemmas related to performing lumbar punctures and interpreting syphilis serologies in patients tested at increasing frequency. The syphilis epidemic represents a public health challenge, but it also presents opportunities. There is an urgent need to control syphilis, to mitigate the morbidity of the infection and its spread, particularly to women, while capitalizing on the diagnosis of syphilis to promote frequent testing for HIV and other sexually transmitted infections, viral suppression among HIV-infected persons, PrEP use, and condoms. This presentation will review the current epidemiology of syphilis and factors contributing to the ongoing syphilis epidemic; key clinical issues in the management of syphilis; and the public health implications of rising syphilis rates. 57 SCALE-UP OF POINT-OF-CARE TESTS FOR SEXUALLY TRANSMISSIBLE INFECTIONS Rebecca J. Guy, Kirby Inst, Univ of New South Wales, Sydney, Australia Diagnosis of sexually transmissible infections is recognized as a key to both individual treatment and public health control, but in many contexts is unavailable or inaccessible, because the diagnostic methods can only be carried out in centralized, sophisticated laboratories. Recent technological advances have generated a variety of new diagnostic options, largely based around testing by the clinician at point-of-care, or self-testing at home. However despite having technical accuracy, the scale up of these technologies in primary health care services faces uncertain pathways and multiple barriers that can impede or even prevent implementation of promising strategies. Large-scale implementation of new point-of-care technology depends on a much wider range of features than simply biological accuracy, including the clinical, social and political context into which the technology is being introduced, and has implications for clinical service delivery, training, quality assurance, data management, supply chains, funding models and the patient experience. This talk will focus on point-of-care and home-based tests that have the potential to substantially increase diagnostic coverage for sexually transmissible infections and implementation research conducted to date to assess their scalability. 58 (PREVENTING) THE COMING EPIDEMIC: HIV IN YOUTH Shannon L. Hader, CDC, Atlanta, GA, USA Youth are essential to achieving bold visions put forward by the global health community for HIV: “Fast-track: Ending the AIDS Epidemic by 2030”, “Delivering on the Promise of an AIDS-free Generation”, and aspiring to ‘super fast-track’ a lifecycle of wellness with “Start Free, Stay Free, AIDS Free” by 2020. Yet even with great gains and more tools in fighting HIV than ever before, shifting demographic patterns add complexity to interrupting HIV transmission and PREVENTING a next epidemic among youth. Successes in global health and child survival, particularly marked in sub-saharan Africa, are paying a ‘demographic dividend’ of the largest population in history of young people aged 12-24, expected to continue to grow through 2035. This session will examine factors critical to understanding HIV risk and response, including: shifting demographics of age and urbanization; fertility patterns and life-cycle windows of risk; HIV incidence by age and gender; contexts of multiple vulnerabilities including violence against children; targeting of age bands and timelines to HIV impact. Given promising structural, behavioral, and biomedical interventions-how do we design and deliver services that ‘fit’ young people for greatest public health impact? This includes reaching youth in periods of risk and reducing contexts of risk; generating demand for services; empowering youth innovation and leadership. Country profiles and possibilities vary, and it will require understanding local evidence, agility in response, and multi-sectoral leadership to achieve dynamic and effective youth-focused HIV responses. 59 ANTIVIRAL VACCINE DEVELOPMENT FROM A (AIDS) TO Z (ZIKA) Barney S. Graham, NIAID, VRC, NIH, Bethesda, MD, USA Infectious diseases pose the greatest threat to public health than any other process. Sir William Osler noted that “Humanity has but three great enemies: fever, famine, and war; of these by far the greatest, by far the most terrible, is fever.” This remains true despite advances in sanitation, antimicrobials, and vaccines. Sustained by increasing global commerce and travel, disruption of ecologies from conflict or economic development, and many people living with immune deficiencies, we are faced with a continuous microbial challenge. Most emerging infectious diseases are caused by viruses and are either zoonotic or vector-borne. AIDS began as a zoonotic transmission that circulated in humans for decades before evolving to the current pandemic. The scientific effort to understand HIV pathogenesis and develop antivirals and vaccine interventions has been a key stimulus driving the evolution of modern immunology. The HIV pandemic illustrated the disruptive impact of infectious diseases on economies and social stability, clarified the importance of taking a global view towards clinical research, and directly led to the development of a substantial worldwide clinical trials infrastructure. Considering the biological and technological challenges involved, one could argue that completing the task of HIV vaccine development is the best approach to generate the tools needed to face any new emerging viral disease. The talk will review lessons learned from the response to pandemic threats over the last 3 decades, and discuss currently available technology options for designing and delivering vaccines against viral diseases that may become future global public health concerns. There are 22 virus families associated with human infection fromwhich the next pandemic threat could arise. Within each relevant virus family a database of information with accompanying reagents, assays, and animal models could be developed for prototypic viruses based on properties of tropism, transmission routes, and other distinguishing features of pathogenesis. Candidate vaccine approaches could be designed based on virus structure, transmission dynamics, entry requirements, tropism, and replication strategy. Rapid isolation of human mAbs, structure-based antigen design, next-generation sequencing, nanoparticle technology, and chemical synthesis are key tools for rapid vaccine development, but advanced preparation will be critical for rapid vaccine deployment during future pandemics.

Oral Abstracts

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CROI 2017