America is staring down a widespread COVID-19 testing shortage with no vaccine in sight. So what happens when coronavirus makes its unceremonious return? Robert Redfield, director of the Centers for Disease Control and Prevention, told that he “can’t guarantee” more stay-at-home requirements in the winter or the fall. “We are committed to using the time that we have now to get this nation as over-prepared as possible.”
“We’ve seen evidence that the concerns it would go south in the southern hemisphere like flu [are coming true], and you’re seeing what’s happening in Brazil now,” Redfield told, “and then when the southern hemisphere is over I suspect it will re-ground itself in the north.”
“This simple respiratory viral pathogen has really brought my nation to its knees, and the reality is, it’s no one particular person’s fault,” he added. (A Columbia University study released this week said up to 36,000 lives could have been saved had U.S. economy shut down even one week earlier.)
‘We are committed to using the time that we have now to get this nation as over-prepared as possible.’
Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases for more than three decades, previously declared, “We will have coronavirus in the fall. I am convinced of that.” He previously said the “ultimate game changer” will be a vaccine, but that could take 12 to 18 months. “If we’re not expecting a second wave or a mutation of this virus, then we have learned nothing,” New York Gov. Andrew Cuomo, CMCSA, -0.53% added, calling it a “new normal” for public health in the U.S. “That is why it is such an important period for government.”
First, the bad news: “The four seasonal coronaviruses do not seem to induce long-term immunity,” said Gregory Poland, who studies the immunogenetics of vaccine response in adults and children at the Mayo Clinic in Rochester, Minn., and expert with the Infectious Diseases Society of America.
“We will not have a vaccine by next winter,” Poland added. “The Southern Hemisphere is just starting their fall and winter. They will have a severe course of this disease due to less preparedness, less medical infrastructure and less public infrastructure.”
“There’s a possibility that the assault of the virus on our nation next winter will actually be even more difficult than the one we just went through,” Redfield, the CDC director, previously told.
Coronavirus immunity differs from other diseases. Immunizations against smallpox, measles or Hepatitis B should last a lifetime, Poland said. Coronaviruses, first discovered in the 1960s, interact with our immune system in unique and different ways, he added.
How do other coronaviruses compare to SARS-CoV-2? People infected by SARS-CoV, an outbreak that centered in southern China and Hong Kong from 2002 to 2004, had immunity for roughly two years; studies suggest the antibodies disappear six years after the infection. For MERS-CoV, a coronavirus that has caused hundreds of cases in the Middle East, people retain immunity for approximately 18 months — although the long-term response to being exposed to the virus again may depend on the severity of the original infection.
The world, Poland said, should brace itself for round two: “We will start moving into our summer when they’re moving into their winter,” he said. “If, as is likely, we don’t restrict all travel, cases will start coming back into the Northern Hemisphere and we’ll have another outbreak this fall.”
Without a vaccine, “herd immunity” is another option. That theory was briefly considered in the U.K. as an alternative to closing businesses and practicing social distancing, but was deemed too risky. Ultimately, enough people would need to be immune to shield the most vulnerable. “There’s no chance that immunity is going to be high enough to reach herd immunity,” Poland said. “With influenza, you need herd immunity of 60% to 70%. With measles, you need about 95%. With COVID-19, it’s somewhere in the middle.”
In the absence of a vaccine, Poland said several conditions are necessary for herd immunity to work: a very high level of population immunity, for that immunity to be durable, and for the virus to not mutate. “None of those seem to be operational at present,” he said.
So what will happen if or when SARS-CoV-2, which causes the respiratory disease COVID-19, returns? “We’re just 14 weeks into this, so no one knows,” Poland said. If it has a slight mutation, he added, the response of our antibodies will be “moderately irrelevant.”
We can’t expect to have the same “herd immunity” or “original antigenic sin” — the ability of our immune systems to remember a virus that is similar, but not the same, as a previous version — as influenza. Influenza, after all, has been around for 500, if not 1,000 years.
“During the great influenza pandemic of 1918, the age group that disproportionately died were young people, not older adults,” Poland said. “Older adults had seen previews of this virus in earlier years, probably in the late 1800s, so they had immunological memory.”
‘The 1918 Spanish flu’s second wave was even more devastating than the first wave. COVID-19’s sweet spot could be October to May.’
“The 1918 Spanish flu’s second wave was even more devastating than the first wave,” Ravina Kullar, an infectious-disease expert with the Infectious Diseases Society of America and adjunct faculty member at the University of California, Los Angeles, told. ♦
