No abstract

No abstract

Available evidence demonstrates that direct patient contact and contact with infectious body fluids are the primary modes for Ebola virus transmission, but this is based on a limited number of studies. Key areas requiring further study include (i) the role of aerosol transmission (either via large droplets or small particles in the vicinity of source patients), (ii) the role of environmental contamination and fomite transmission, (iii) the degree to which minimally or mildly ill persons transmit infection, (iv) how long clinically relevant infectiousness persists, (v) the role that “superspreading events” may play in driving transmission dynamics, (vi) whether strain differences or repeated serial passage in outbreak settings can impact virus transmission, and (vii) what role sylvatic or domestic animals could play in outbreak propagation, particularly during major epidemics such as the 2013–2015 West Africa situation. In this review, we address what we know and what we do not know about Ebola virus transmission. We also hypothesize that Ebola viruses have the potential to be respiratory pathogens with primary respiratory spread.

Rarely have studies focused on the secondand third-order effects of pandemics. Limiting the disruption of critical infrastructures during a pandemic is important for the survival and health of society (i.e., electricity, water, and food) as most medical and public health responses to a pandemic depend on these infrastructures. The studies that have looked at this issue have highlighted alarming gaps in preparedness. This study used a system dynamics model to demonstrate the likely effects of a pandemic on the USA's food system. The model reveals that a severe pandemic with greater than a 25 % reduction in labor availability can create significant and widespread food shortages. The Ebola epidemic that began in 2014 has caused severe food shortages in West Africa, which are similar to the effects that this model predicts in the USA. The likely effects of the reduction in the amount of available food are difficult to specifically predict; however, it is likely to have severe negative consequences on society. The resilience of the food system must be improved against this hazard and others.

Two recently submitted (but as yet unpublished) studies describe success in creating mutant isolates of H5N1 influenza A virus that can be transmitted via the respiratory route between ferrets; concern has been raised regarding human-to-human transmissibility of these or similar laboratory-generated influenza viruses. Furthermore, the potential release of methods used in these studies has engendered a great deal of controversy around publishing potential dual-use data and also has served as a catalyst for debates around the true case-fatality rate of H5N1 influenza and the capability of influenza vaccines and antivirals to impact any future unintentional or intentional release of H5N1 virus. In this report, we review available seroepidemiology data for H5N1 infection and discuss how case-finding strategies may influence the overall case-fatality rate reported by the WHO. We also provide information supporting the position that if an H5N1 influenza pandemic occurred, available medical countermeasures would have limited impact on the associated morbidity and mortality.