Chapter 1: The Continuing Reality of Coronavirus

The coronavirus responsible for COVID-19 has infected over 16.5 million individuals across all six continents. It continues to spread aggressively in nations that struggled to contain it, while also resurging in those that previously managed to do so. The window for containing this virus seems to have closed. One conclusion appears increasingly inevitable: the virus is here to stay.

This virus is far too prevalent and highly transmissible. Experts suggest that while the pandemic might eventually subside—thanks to widespread infection or vaccination—the virus will likely remain in circulation at lower levels globally. We can expect case numbers to fluctuate, with outbreaks occurring sporadically. Even with the introduction of a long-awaited vaccine, it is probable that the virus will only be subdued, rather than completely eliminated. Historically, despite vaccines being developed for numerous viruses, only smallpox has been completely eradicated—an achievement that took an extraordinary 15 years of global cooperation. It is likely we will coexist with this virus for the foreseeable future.

In the previous winter, public health officials held more optimistic views regarding SARS-CoV-2, the virus causing COVID-19. In contrast, SARS—a related coronavirus—emerged in late 2002 and infected over 8,000 people, but was eradicated through rigorous isolation, contact tracing, and quarantine measures by 2004. The crucial difference between the two viruses is the greater ease with which SARS-CoV-2 spreads, often without noticeable symptoms. The strategies that effectively quelled SARS are much less effective against a virus that can spread silently. “It’s very unlikely we’re going to be able to declare the kind of victory we did over SARS,” notes epidemiologist Stephen Morse from Columbia University.

What does the future hold for COVID-19? The answer may hinge on the durability of immunity against the virus, according to Yonatan Grad, an infectious disease researcher at Harvard. He and his team have theorized several possible future scenarios. If immunity proves short-lived—lasting just a few months—we could face a significant resurgence followed by smaller annual outbreaks. Alternatively, if immunity lasts around two years, COVID-19 might peak every other year.

At this stage, the longevity of immunity to COVID-19 remains uncertain, as the virus has not been infecting humans long enough for us to draw definitive conclusions. However, studies of similar coronaviruses provide some insights: for instance, antibodies from SARS fade after approximately two years, while those from other coronaviruses that cause common colds diminish within a single year. “The quicker immunity wanes, the more challenging it becomes to aim for eradication,” Grad explains.

This uncertainty also applies to vaccine development. Instead of a one-time solution, a COVID-19 vaccine might necessitate regular booster shots to maintain immunity. This could mean annual or biennial vaccinations, similar to flu shots.

Even if we could eradicate the virus from humans, it could still persist in animal populations, potentially reinfecting humans. SARS-CoV-2 likely originated from bats, possibly with another unidentified animal acting as an intermediary host that could continue to harbor the virus. Timothy Sheahan, a virologist at the University of North Carolina at Chapel Hill, raises concerns about the potential for humans to transmit the virus to new species, thus creating additional animal reservoirs. “How do you begin to know the extent of virus spread outside of the human population and in wild and domestic animals?” he asks. So far, instances of tigers at the Bronx Zoo and minks on Dutch farms contracting COVID-19 from humans—and in the case of the minks, transmitting it back—have been documented.

The existence of animal reservoirs complicates discussions of “eradication” for these viruses. For instance, while human-to-human transmission of Ebola ceased following the 2016 West African epidemic, the virus still exists in nature and could potentially infect humans again if the right conditions arise. In fact, Ebola resurfaced in the Democratic Republic of the Congo in 2018. Although containment strategies and new vaccines can effectively manage Ebola, complete eradication remains elusive. While it's unclear why SARS has not reemerged from an animal reservoir, SARS-CoV-2 may follow a different trajectory.

In a best-case scenario, advancements in vaccines and treatments could mitigate the severity of COVID-19, transforming it into a less dangerous and disruptive illness. Over time, SARS-CoV-2 could evolve into just another seasonal respiratory virus, akin to the four other coronaviruses responsible for a significant share of common colds: 229E, OC43, NL63, and HKU1. These cold coronaviruses are so prevalent that most of us have likely encountered them multiple times throughout our lives. While they can cause severe outbreaks, especially among the elderly, they usually manifest as mild illnesses that go largely unnoticed. One potential outcome is that SARS-CoV-2 evolves into the fifth coronavirus that routinely circulates among humans.

Interestingly, virologists have speculated whether common cold coronaviruses began as pandemics before becoming regular viruses. For instance, research in Belgium from 2005 examined mutations in the cold coronavirus OC43, which likely evolved from a coronavirus infecting cows. By analyzing genetic mutations, researchers estimated that the spillover from cows to humans occurred in the late 1800s, coinciding with a deadly respiratory illness affecting both cattle and humans around that time. This illness, which caused malaise, fever, and severe central nervous system symptoms, was initially linked to influenza based on antibodies found in survivors decades later, although its exact cause remains unproven.

Could this illness have been a coronavirus that jumped from cows to humans? While these connections are speculative, Burtram Fielding, a coronavirus researcher at the University of the Western Cape, suggests that such a possibility shouldn't be dismissed. “But,” he adds, “I wouldn’t be surprised.” If true, this would indicate that COVID-19 could gradually become less lethal over time, transitioning from a pandemic to something more akin to a common cold.

In general, viruses often face a trade-off between their contagiousness and lethality. The cases of SARS and SARS-CoV-2 illustrate this point: while SARS was more deadly, it spread less efficiently. Ultimately, a virus's goal is to perpetuate itself, making it advantageous to infect living hosts rather than killing them. “In the grand scheme of things, a dead host doesn’t help the virus,” comments Vineet Menachery, a coronavirus researcher at the University of Texas Medical Branch. The four coronaviruses associated with common colds may also be less deadly because most individuals are exposed to them during childhood. Although immunity doesn't prevent reinfection, it can mitigate severe disease. This, combined with vaccine-induced immunity, suggests that COVID-19 will likely become less disruptive over time.

Influenza serves as another valuable point of reference. The term “flu” encompasses various strains that circulate seasonally. After pandemics such as the 2009 H1N1 outbreak, the pandemic strain does not simply vanish; instead, it morphs into a seasonal variant that remains in circulation year-round but peaks during winter. A descendant of the 2009 H1N1 strain continues to circulate as a seasonal flu today. While seasonal peaks never quite reach pandemic levels due to population immunity, new strains can emerge, triggering fresh pandemics that eventually become the dominant seasonal strain.

Thus, the long-term perspective for COVID-19 may offer some optimism for a return to normalcy. “I think this virus is with us in the future,” states Ruth Karron, a vaccine researcher at Johns Hopkins. “But so is influenza, and for the most part, flu doesn’t shut down our societies. We manage it.”

Chapter 2: Perspectives on the Future of COVID-19

In the video titled "Will COVID-19 ever go away? | Inside Story," experts discuss the ongoing implications of COVID-19 and whether it will eventually fade from public concern.

In another insightful video, "WHO Says Covid-19 'May Never Go Away'," the World Health Organization explores the likelihood that COVID-19 will remain a persistent challenge for global health.