The Coronavirus Could Mutate Into Something Far Worse: Lessons From the 1918 Flu Pandemic
We have plenty of good reasons to worry about the coronavirus (COVID-19). It spreads rapidly. There is no vaccine. People die from it. Yet the virus could change and make the epidemic worse. Younger people might even ultimately be hit hardest of all. That is exactly what happened during the 1918 global influenza contagion.
Arlene W. Keeling, writing in Health Emergency and Disaster Nursing, describes how the 1918 flu changed from its initial mild outbreak in the spring of 1918 to a virulent second wave that appeared in the late summer and early fall. The virus changed — through a mutation or other means — and became more infectious and deadlier. When the disease finally receded in 1919, it “caused over 675,000 deaths in the United States of America and over fifty million worldwide.”
The change was as abrupt as it was savage. The second wave hit New Zealand so quickly that the outbreak was tied to a single ship. The RMS Niagara left Vancouver and then San Francisco before the virus intensified, and when it docked in Auckland, passengers and crew showed only signs of “ordinary influenza.” No quarantine measures were taken, and when the illness took a sharp turn for the worse in the country two weeks later, anger focused on Prime Minister William Massey. Massey was on the ship and rumor had it that he pulled strings to prevent a quarantine. This is doubtful, however, and it remains unclear to this day if the Niagara carried a mutation, “a deadly hybrid” of the virus, or perhaps had no connection with the second wave at all.
Sudden global waves of influenza naturally generate intense public concern and lead to comparisons of a pandemic to a tornado — it drops from nowhere, wrecks things quickly, and is gone. This is incorrect, according to a 2005 Institute of Medicine of the National Academies report, The Threat of Pandemic Influenza: Are We Ready? Instead of a tornado-like quality, the report says the 1918 and subsequent pandemics offered “epidemiologic warning signs” and played out “over several years.” In this view, the first outbreak of the 1918 flu is regarded as a “herald wave” that preceded the “majority of the mortality impact” a few months later.
Disturbingly, the report also highlights what it terms “the pandemic age shift” that happened during the last three flu pandemics. An analysis of age-specific mortality data in New York City for the 1918–1919 flu shows a dramatic spike in the death rate for people under 45 during the second wave of contagion. “The age groups at highest absolute risk of dying … were young children and young and middle-aged adults.” In the concluding section, the report states that while mortality impact for future pandemics are difficult to predict, “a shift to younger ages is highly likely.”
Whether this is the case for COVID-19 is, of course, unknown. The virus is novel and may run a course different from other pandemics. Our modern health practice and infrastructure are also vastly better than they were a hundred years ago. There is also hope for a vaccine in about a year. Lessons from the past, however, warn that we should take the current pandemic seriously for months to come.
