Reviewing the History of Pandemic Influenza: Understanding Patterns of Emergence and Transmission

Abstract

For centuries, novel strains of influenza have emerged to produce human pandemics, causing widespread illness, death, and disruption. There have been four influenza pandemics in the past hundred years. During this time, globalization processes, alongside advances in medicine and epidemiology, have altered the way these pandemics are experienced. Drawing on international case studies, this paper provides a review of the impact of past influenza pandemics, while examining the evolution of our understanding of, and response to, these viruses. This review argues that pandemic influenza is in part a consequence of human development, and highlights the importance of considering outbreaks within the context of shifting global landscapes. While progress in infectious disease prevention, control, and treatment has improved our ability to respond to such outbreaks, globalization processes relating to human behaviour, demographics, and mobility have increased the threat of pandemic emergence and accelerated global disease transmission. Preparedness planning must continue to evolve to keep pace with this heightened risk. Herein, we look to the past for insights on the pandemic experience, underlining both progress and persisting challenges. However, given the uncertain timing and severity of future pandemics, we emphasize the need for flexible policies capable of responding to change as such emergencies develop.

Dissecting host cell death programs in the pathogenesis of influenza

“…In 1918, the worst pandemic in recorded history caused more than 50 million deaths worldwide [3]. Since then, three other pandemics have occurred: first in 1957, then again in 1968 and finally in 2009 [4]. Currently, there are major concerns surrounding the emergence of the new highly pathogenic avian influenza (HPAI) viruses of H5N1, H7N9, H10N8, or the more recent H5N8dthe only HPAI strain to cross from Eurasia to America [5e9].…”

pH Optimum of Hemagglutinin-Mediated Membrane Fusion Determines Sensitivity of Influenza A Viruses to the Interferon-Induced Antiviral State and IFITMs

“…Although zoonotic IAVs are not transmitted from human to human, some of them, such as the poultry H5N1 and H7N9 viruses, can cause unusually severe human disease and fatalities (for reviews, see references 1 to 4). On rare occasions, animal viruses become adapted to humans, initiate global pandemics, and continue to circulate and evolve in humans for decades, causing annual seasonal influenza outbreaks (5,6). Thus, influenza disease in humans can be caused by seasonal, pandemic, and zoonotic viruses that have distinguishable properties.…”

Transportation and _______

“…As ever more modern transportation technology produced faster speeds, transportation became an even greater enabler of a pandemic (Wilson, 1995). Saunders-Hastings and Krewski (2016), who examined pandemics since the late 1500s, noted that the state of transportation technology was a likely contributor to the time it took for a disease to spread.…”