Preparing intensive care for the next pandemic influenza

Abstract

Few viruses have shaped the course of human history more than influenza viruses. A century since the 1918-1919 Spanish influenza pandemic-the largest and deadliest influenza pandemic in recorded history-we have learned much about pandemic influenza and the origins of antigenic drift among influenza A viruses. Despite this knowledge, we remain largely underprepared for when the next major pandemic occurs.While emergency departments are likely to care for the first cases of pandemic influenza, intensive care units (ICUs) will certainly see the sickest and will likely have the most complex issues regarding resource allocation. Intensivists must therefore be prepared for the next pandemic influenza virus. Preparation requires multiple steps, including careful surveillance for new pandemics, a scalable response system to respond to surge capacity, vaccine production mechanisms, coordinated communication strategies, and stream-lined research plans for timely initiation during a pandemic. Conservative models of a large-scale influenza pandemic predict more than 170% utilization of ICU-level resources. When faced with pandemic influenza, ICUs must have a strategy for resource allocation as strain increases on the system.There are several current threats, including avian influenza A(H5N1) and A(H7N9) viruses. As humans continue to live in closer proximity to each other, travel more extensively, and interact with greater numbers of birds and livestock, the risk of emergence of the next pandemic influenza virus mounts. Now is the time to prepare and coordinate local, national, and global efforts.

Keywords: Health care worker safety; Highly pathogenic avian influenza; Human; Influenza; Intensive care; Pandemic; Preparation; Research; Resource allocation; Triage.

Fig. 1

Timeline of recorded influenza outbreaks in the past century as well as selected avian influenza outbreaks in humans. In the main figure, globe size corresponds to the estimated number of fatalities relative to global population size at the time, with vertical bars representing the estimated absolute number of fatalities. Numbers are averages from various approximations. In inset, horizontal bars represent time frame that cases from the influenza A virus strain were recorded

Fig. 2

a Stages of mass critical care, with various ICU response thresholds. As a pandemic progresses, resources become scarce and there is increasing strain placed on the health care system from more cases [24]. b A potential triage strategy for various patient groups as the capacity of the ICU is slowly overwhelmed to streamline admissions without the greatest opportunity for benefit from ICU level care. Transparency is paramount in this process