The truth about pandemics: 5 questions about COVID-19 and flu
James Downing, MD, president and CEO of St. Jude, recently sat down with two of the world’s preeminent experts to discuss the intersection of COVID-19 and flu: Richard Webby, PhD, member of the Infectious Diseases Department and director of the World Health Organization Collaborating Center for Studies on the Ecology of Influenza in Animals and Birds, and Robert Webster, PhD, emeritus faculty member. Webster is responsible for finding the link between the world’s influenza virus reservoir and migratory aquatic birds. He dedicated his career to hunting flu viruses and helping the world better prepare for the next pandemic.
Webby and Webster offer brief insights into five of those questions:
Where do coronaviruses come from?
Webby: There are four coronaviruses that already circulate in humans, and they all started as viruses of other animals that leapt over into humans. SARS-CoV-2, the virus that causes COVID-19, is another one of these. This virus came out of wildlife in China, moved into the wholesale live-animal markets and jumped over into humans within that environment. That’s our best guess.
What part did China’s live-animal markets play in this pandemic?
Webster: The animal markets of Asia go back to ancient times. Without refrigeration, particularly in southern China, it’s impossible to keep meat fresh. To solve that problem, centuries ago, they introduced live-animal markets, particularly live-poultry markets. Over time, the live-poultry markets contained not only chickens, ducks and geese, but also wild animals. The meat from the wild animals is thought of as a specialty. The SARS-CoV-1 outbreak of 2003 came from a horseshoe bat and went through an intermediate host, a civet cat.
Colleagues that I trained here at St. Jude went back to Hong Kong and characterized not only the intermediate host, but that these viruses were coronaviruses.
In these markets, the animals are not kept separately. That is the difficulty. They’re stacked six or eight high, sometimes with chickens and ducks in the same cage, sometimes with a dog in the corner, and a civet cat somewhere else. This is the perfect breeding ground for viruses.
Usually the women do the shopping, and they bring their children with them to the markets. Sometimes, they will actually take a bird from the cage to feel that it’s nice and plump. If they decide it is, the bird is slaughtered right there. This is a perfect place for transmission. The very idea that COVID-19 emerged from a laboratory and not naturally is abhorrent to me. We know that this has occurred many, many times in nature. We know how it occurred. Bat studies in China in the last few months have isolated 10 different coronaviruses out of one cave. There’s a huge plethora of viruses in bats that we know little or nothing about.
What about immunity? Will this virus be with us forever?
Webby: That’s the $64,000 question. So, my best guess is that this virus will be with us forever, but I think we’ve got a period of time to get through, and then it will settle down into a more perhaps common cold-like virus, at worst perhaps more of a flu. That’s what all these viruses have done. They come over from animals into humans. Humans have no immunity at all, so there’s a period of rampant disease, and then it settles down into something we can live with.
What will happen during the coming flu season?
Webby: My answer is going to be completely unsatisfactory here, because we just don’t know. Essentially, we have two ends of this. One, we’re going to have two severe respiratory viruses circulating at the same time—perhaps complicating diagnoses, complicating the infection. Two, flu activity has been incredibly low in the southern hemisphere. A lot of that probably is because people are wearing masks and social distancing—and it turns out, that works really well against flu and other respiratory viruses, too. So we could be at either end of the spectrum. We just don’t know, and that’s the problem.
It’s incredibly important to get flu shots this year. If these two viruses do circulate at the same time, it’s really going to complicate things. But if we can vaccinate ourselves, and at least get as much flu out of the equation as we can, then it’s a no-brainer.
Webster: It’s absolutely essential that everyone takes the vaccine. We cannot ever predict the severity of flu. That’s one of the unanswered questions for the future.
How long will it be before this pandemic is over—so that we can go back to the beach, watch our kids play baseball, or attend sporting events?
Webster: When a vaccine is approved, it’s important that we take it. You’re in control of deciding whether or not we go back to playing ball next summer. If you help raise the herd immunity to 70% plus, we’ll be back there. If you don’t do it, we won’t. Take the vaccine—not just flu vaccine, but the future COVID-19 vaccine. It’s an absolute must. The vaccine may not protect you for more than a few months, but you’ll have immunological memory for the rest of your life—and you will not die if you get hit with that virus.
Downing: It really is in the public’s hands. As the vaccines become available, take them. Get vaccinated, so that we can go back to a normal life. It’s going to require all of us working together to accomplish that.