Demonstrating vaccine effectiveness during a waning epidemic: A WHO/NIH meeting report on approaches to development and licensure of Zika vaccine candidates.

Since its peak in early 2016, the incidence of Zika virus (ZIKV) cases has declined to such low levels that Phase 3 field efficacy trials may be infeasible. While great progress was made to rapidly advance several vaccine candidates into Phase 1 and 2 clinical trials, in the absence of sustained viral transmission it may be difficult to evaluate the effectiveness of ZIKV vaccine candidates by conducting traditional clinical disease endpoint efficacy studies. However, ZIKV is still circulating at low levels in some areas and is likely to re-emerge in naïve populations or in sites of prior epidemics once population immunity wanes. Therefore, the public health need for a ZIKV vaccine remains. To facilitate continued ZIKV vaccine development efforts, the World Health Organization's Initiative for Vaccine Research and the National Institutes of Health's National Institute of Allergy and Infectious Diseases co-hosted a meeting of experts in March 2018 to identify strategies to demonstrate vaccine effectiveness in view of waning ZIKV disease incidence. This paper outlines points for consideration for developers, regulators, and other stakeholders working towards a licensed ZIKV vaccine. These deliberations may also be applicable to development of vaccines for other emerging infections where the size, unpredictability, and ephemeral nature of outbreaks makes clinical disease endpoint efficacy trials to demonstrate vaccine effectiveness infeasible.

What Recent History Has Taught Us About Responding to Emerging Infectious Disease Threats.

Presidential administrations face any number of unexpected crises during their tenure, and global pandemics are among the most challenging. As of January 2017, one of the authors had served under 5 presidents as the director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health. During each administration, the government faced unexpected pandemics, ranging from the HIV/AIDS pandemic, which began during the Reagan administration, to the recent Zika outbreak in the Americas, which started during the Obama administration. These experiences underscored the need to optimize preparation for and response to these threats whenever and wherever they emerge. This article recounts selected outbreaks occurring during this period and highlights lessons that were learned that can be applied to the infectious disease threats that will inevitably be faced in the current presidential administration and beyond.

The Pathway to a Universal Influenza Vaccine.

Development of a universal influenza vaccine is a research priority for the National Institute of Allergy and Infectious Diseases (NIAID) at the National Institutes of Health. To facilitate this goal, we convened a workshop in Rockville, Maryland to identify knowledge gaps in influenza research and develop strategies to fill them.

Antimicrobial Resistance.

IMPORTANCE: The development of antibiotics is considered among the most important advances of modern science. Antibiotics have saved millions of lives. However, antimicrobial resistance (AMR) threatens this progress and presents significant risks to human health. OBJECTIVE: To identify factors associated with AMR, the current epidemiology of important resistant organisms, and possible solutions to the AMR problem. DATA SOURCES, STUDY SELECTION, AND DATA SYNTHESIS: PubMed (2000-2016), NIH REPORTER, and ClinicalTrials.gov databases were searched for articles and entries related to AMR, focusing on epidemiology, clinical effects of AMR, discovery of novel agents to treat AMR bacterial infections, and nonpharmacological strategies to eliminate or modify AMR bacteria. In addition to articles and entries found in these databases, selected health policy reports and public health guidance documents were reviewed. Of 217 articles, databases, and reports identified, 103 were selected for review. RESULTS: The increase in AMR has been driven by a diverse set of factors, including inappropriate antibiotic prescribing and sales, use of antibiotics outside of the health care sector, and genetic factors intrinsic to bacteria. The problem has been exacerbated by inadequate economic incentives for pharmaceutical development of new antimicrobial agents. A range of specific AMR concerns, including carbapenem- and colistin-resistant gram-negative organisms, pose a clinical challenge. Alternative approaches to address the AMR threat include new methods of antibacterial drug identification and strategies that neutralize virulence factors. CONCLUSIONS AND RELEVANCE: Antimicrobial resistance poses significant challenges for current clinical care. Modified use of antimicrobial agents and public health interventions, coupled with novel antimicrobial strategies, may help mitigate the effect of multidrug-resistant organisms in the future.

Emerging viral diseases: confronting threats with new technologies.

Emerging viral diseases pose ongoing health threats, particularly in an era of globalization; however, new biomedical research technologies such as genome sequencing and structure-based vaccine and drug design have improved our ability to respond to viral threats.

Ending the global HIV/AIDS pandemic: the critical role of an HIV vaccine.

While the human immunodeficiency virus (HIV)/AIDS pandemic continues, the incidence of HIV infections has fallen because of the deployment of antiretroviral drugs and multiple prevention modalities. To achieve a durable end to the pandemic, a vaccine remains essential. Recent advances in vaccinology offer new promise for an effective HIV vaccine.