by John J. Dalton, FHFMA, Editor, The Three Minute ReadTM
The word “endemic” comes from the Greek endēmos, which means “in population.” An endemic virus is relatively constant in a population with largely predictable patterns, with the seasonal flu perhaps the best example. It’s likely that Covid-19 ultimately will achieve endemic status – it isn’t going away.
To start with, it’s helpful to understand what the differing terms mean, and epidemiologists and public health experts differentiate among outbreak, epidemic, pandemic and endemic as follows:
Each virus has defining characteristics ranging from speed of replication to lethality and drug resistance. That’s been clear as SARS-CoV-2’s Alpha, Delta, Omicron and Omicron variants and subvariants have each become more transmissible but cause differing symptoms and varying degrees of vaccine and drug resistance.
John M. Barry, author of “The Great Influenza: The Story of the Deadliest Pandemic in History,” offers a word of caution to those seeking to abandon precautions. While most histories of the 1918 pandemic say it ended in the summer of 1919 when a third wave of the respiratory contagion finally subsided, a variant that emerged in 1920 was lethal enough that it should have counted as a fourth wave. It occurred even though the U.S. population had plenty of natural immunity from the influenza virus after two years of several waves of infection. In 1921, the virus mutated into ordinary seasonal influenza.
Most public health experts currently agree that Covid is here to stay. So, when will Covid reach endemic status? The scientific consensus seems to be that it will occur when enough Americans gain immune protection from vaccination and/or from having been infected that there will be less transmission and much less Covid-related hospitalization and death, even as the virus continues to circulate.
Within the U.S., the Northeast is most likely to attain endemic status first, achieving herd immunity through vaccination or infection. The long and winding road to endemic status is likely to throw some more twists and turns our way before America can be fully comfortable coexisting with Covid. Over time and with sustained public health efforts ranging from mask wearing to vaccination and wastewater monitoring, the Covid pandemic could gradually become endemic.