With the omicron surge over in many countries, discussions are turning to when the pandemic might end — and what the end might look like. Scientists, public health experts, and policy makers are starting to talk about how COVID-19 might be on its way to becoming “endemic” — a manageable threat — instead of a crisis that sends daily life into chaos, overwhelms our healthcare system, and disrupts the economy. Globally, 456 million people have been diagnosed with confirmed cases of COVID-19 and six million have died from the disease, according to the World Health Organization (WHO), with more than 1.2 million individuals contracting COVID-19 every day. But we may be in a new and more stable phase of the pandemic, experts say. That’s because so many individuals are at least somewhat protected against COVID-19, either because they’ve been vaccinated (and possibly boosted) or because they’ve been infected with the coronavirus and so have at least some level of natural immunity. “This pandemic, like all other pandemics before it, will end, but it is far too early to relax,” said Hans Henri P. Kluge, PhD, the WHO’s regional director for Europe, in a statement. Several public health measures may help hasten the shift to endemic COVID-19, Dr. Kluge added. These include monitoring the virus to see whether it begins to spread through communities and to watch for new variants; testing for COVID-19 in targeted ways; and working to get more people vaccinated and boosted. Masking and physical distancing may also be required in certain situations, Kluge said, especially for high-risk individuals. His conclusion: If we can do all of these things, new waves of infections or new variants may no longer force us to return to draconian measures like widespread lockdowns.
Endemic vs. Pandemic
What Kluge and other public health experts envision as the end game for COVID-19 amounts to the disease becoming endemic. To understand what that means, here’s a quick rundown of the course that infectious diseases can take as they spread. As with COVID-19, which originated in Wuhan, China, many diseases begin as local outbreaks. A disease outbreak refers to a situation when there is a sudden surge of cases within a limited geographic area, which has occurred in recent years with conditions such as measles and Ebola, according to the Centers for Disease Control and Prevention (CDC). When cases spread rapidly across a wider geographic area, public health officials may then define the situation as an epidemic, the CDC notes. The CDC has described a wide range of situations as epidemic over the years, including HIV and antibiotic-resistant germs known as “superbugs.” When epidemics strike in multiple countries or spread across many continents, then a disease or health problem is considered a pandemic. Numerous influenza viruses have sparked pandemics, says the CDC, including the so-called Spanish flu of 1918, which killed 50 million people worldwide. By contrast, case levels need to hold steady at a lower level in the community in order for a disease to be considered endemic, rather than pandemic, according to the CDC. For example, malaria is endemic in some regions of the world where it spreads at a consistently low level within communities.
How COVID-19 May Become Endemic
Increased immunity among those who have recovered from COVID-19, aided by vaccinations and booster shots, will go a long way towards transforming COVID-19 from a pandemic to endemic, says Marc Veldhoen, PhD, a professor of immunology at the University of Lisbon in Portugal. From the early days of the pandemic, immunologists anticipated that COVID-19 would eventually become endemic. With other viral illnesses like the seasonal flu, vaccination and immunity from prior infection play a key role in creating conditions for endemic disease, and immunologists anticipate that COVID-19 will be similar in this regard. “Immunity is rapidly — and with vaccinations, safely — increasing,” Dr. Veldhoen says. Once people are vaccinated, or once they’ve had COVID-19, any future infections may be easier for their immune systems to fight off, Veldhoen explains. Over time, this forces the virus to evolve into variants that move more quickly through the body and cause milder illnesses more similar to the common cold than to severe disease. But endemic COVID-19 may still be more dangerous than the common cold, especially to high-risk populations like the elderly and individuals with compromised immune systems. It may become more like seasonal influenza in this respect, Veldhoen says: a viral infection that can kill people who are medically vulnerable.
An Annual COVID-19 Vaccine Might Target Certain Variants
Down the line, scientists may strive to create an annual COVID-19 vaccine that, like the influenza vaccine, targets the variants predicted to be dominant, Veldhoen says. Public health officials may recommend annual COVID-19 vaccinations for most children and adults, says Robert M. Wachter, MD, professor and chair of the department of medicine at the University of California in San Francisco. It might even be possible to one day have a single combination vaccine available each year that protects against common variants of both influenza and COVID-19, Dr. Wachter adds. “There will still be virus around, but few people will be unprotected, and the virus is somewhat milder, so that combination will lead to fewer and milder infections,” Wachter says. When people do get infected, improved access to effective medications like the antiviral pill Paxlovid may help prevent severe illness and death. “All in all, could be a very good situation,” Wachter says about this endemic scenario.
