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[Anniversary Special] ‘Will COVID-19 end?’ Top vaccine expert urges hopeful patience

최만섭 2021. 8. 13. 05:46


Our exit from the COVID-19 pandemic will be a gradual process, with the ferocious beast becoming progressively less threatening until it becomes something we can live with, says the International Vaccine Institute’s director general, Dr. Jerome H. Kim.

“Successful vaccination turns the tiger that is COVID-19 into an alley cat. Many fewer people will end up in hospitals or on ventilators, and deaths will be very rare,” he said. Real-world experience from better-vaccinated parts of the world shows there is “a promise of a better future.”

“The cat doesn’t go away, but it’s something that we can live with.”

More than a year and a half into the pandemic, a reminder was in order that this is “not a single battle, but a war,” he said.

“There will be triumphs and reverses. The objective in the end is to win the pennant, and we have to be patient.”


What will it take to get normal back?

Kim said the delta variant of the virus has changed the calculus behind herd immunity. The estimated minimum vaccination threshold of 70 percent, which was based on what we knew about the original virus, now needs to be higher.

“The infectiousness of delta appears to be close to that of chickenpox, and that may change the number of people who need to be vaccinated. We would need to have vaccination rates of over 80 percent, or even higher,” he said.

“I would expect that Korea will start to see an impact as we pass 50-60 percent -- ideally fully vaccinated, which is necessary for delta, and further incremental decreases will be seen as we hit 70-80 percent. Korea should aim for higher than 90 percent, eventually, and I would include children in the total number.”

Now may be a time to start defining what success against COVID-19 means, he said, “which won’t necessarily be the absence of infections, but the control of bad outcomes from the disease.”

When we get to that point, what we monitor will not be the number of PCR-positive infections, but the number of hospitalizations, alongside a survey of mild infections and sequencing of variants, he said.

“In the end, we may be able to think of COVID-19 like we do about measles -- not eradicated globally, but no domestic transmission. Cases can be imported, but vaccination will keep them from becoming large outbreaks,” he said. “Hopefully this isn’t too optimistic a scenario.”


For now, distancing and masks stay

“One of the things that may be a bit unusual about delta is that even after you’re vaccinated, if you become infected, the amount of virus that can be sampled from your nose or throat is almost the same as a person who’s not been vaccinated,” he said.

“That’s the reason why even if you’ve been vaccinated, you should continue to wear masks until enough people are vaccinated, because you can spread it to other people just as readily.”

When masks are added, the evolution of the virus is also slower, especially in the setting of a larger outbreak.

“If Korea were vaccinating slowly back in the summer of last year when it had few infections, the mutation rate wouldn’t be very great at all. But when you’re vaccinating in the middle of an outbreak, then you can run into problems,” he said.

“To vaccinate and continue to use masks is the correct approach, and it’s the approach that appears to decrease the development of vaccine-resistant mutants.”

As for hasty calls for dropping restrictions, he said, “In countries that opened up too soon, we’ve witnessed that the pandemic then turns to the unvaccinated adults and children. We don’t want to relearn the horrible and tragic lessons country after country.”

He pointed out that even with the current wave, low by comparison to other parts of the world, hospitals in South Korea are struggling.

“All you need to do is look at the hospitals. Past a certain capacity, you’re going to be seeing patients who are denied access to care -- not just patients with COVID-19, but patients with other conditions that require intensive care.”


Variant-proof vaccines in the works

So far the virus has been making “pretty predictable” mutations, largely in terms of its transmissibility, he said. Delta is still covered by the vaccines, for one thing.

“But there’s a strain found in Latin America called lambda, which is a little more resistant to some of the protective immune responses that are induced by the vaccine,” he said.

“The delay in implementation of vaccination in countries around the world, and the lack of their ability to control the outbreaks through distancing and masks have meant that a lot more mutations have arisen,” he said. “During these uncontrolled outbreaks, the virus is mutating, and we fear that the virus could mutate to become both transmissible and resistant.”

He said in a sense, it was “a race between our ability to vaccinate enough people while the vaccines are still effective, and the ability of the virus to change itself.”

Hope is growing that new, better vaccines are on the way. Scientists are now working on what is called a universal vaccine that will work against multiple variants, he said.

“They’re already making variant vaccines, much like the multivalent vaccine -- three or four vaccines in one type -- that we have against influenza. Another way is to figure out the right set of changes in the spike protein that will make it applicable not only to the current viruses, but to the future viruses as well,” he said.

“Whether we will need one vaccine or a combination of different vaccines is something we don’t know yet,” he said. “The process of testing and reviewing the new vaccines will hopefully be faster, since they’re similar to ones that have been used, except this time they cover a much broader range of strains.”


No country safe until world is vaccinated

Ultimately, our vaccination efforts must go beyond the borders of each country, he said.

“We wouldn’t have to have a new mutant like delta somewhere else in the world that could all of a sudden appear in Korea,” he said. “So we have to track what the ongoing threats are outside of Korea.

For South Korea, the country’s neighbors in the North going unvaccinated raises concerns.

“It’s a big problem for the people of North Korea, and then potentially for the rest of the world -- countries in particular that have a lot of traffic with North Korea over the border, and through other trade means. Potential exists there to be both mutants and transmission.”

He warned that “all countries in this world have to be considered a part of the solution. Otherwise, they will become a part of the problem.”

Still, the paramount task at the moment remains putting into place an impactful vaccination program that can rein in the virus at least within individual countries. “That will be the first job because if we can do that, then maybe we can start extending it the same way measles was eliminated,” he explained.

“I know that the government’s first responsibility is to the people of Korea,” he said, as it is for places elsewhere to first protect their own.

“On the other hand, they have purchased a lot of vaccines and some of it should be moved over to the mechanism that distributes them to help countries around the world. I know the Korean government has committed to this.

“We should try actively to vaccinate as many people as possible around the world.”


On Aug. 15, 2021, The Korea Herald celebrates its 68th anniversary as South Korea’s No. 1 English-language daily. To mark the day in a time of pandemic and turmoil, The Korea Herald has prepared a series of stories on the challenges that we face and the prognosis for life with, or after COVID-19. -- Ed.


By Kim Arin (arin@heraldcorp.com)