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China battles biggest surge in Covid cases since original Wuhan outbreak
03:41 - Source: CNN

Editor’s Note: Kent Sepkowitz is a physician and infection disease expert at Memorial Sloan Kettering Cancer Center in New York. The views expressed in this commentary are his own. View more opinion on CNN.

CNN  — 

Here we go again (and again). Another wave of the virus that causes Covid-19 has been spreading across parts of the globe, just as things seemed to be returning to normal in the United States. The perpetrator, called the BA.2 subvariant of the Omicron variant, already accounts for 23% of all US cases, though total cases have not begun to rise nationally.

This development leads us – again – to the crucial question: Will the latest surge in Europe, Asia, Australia and South America, much of it driven by the BA.2 subvariant, come to the United States? And it leads us – again – to the same carefully parsed answer (with the usual disclaimer that all Covid-19 predictions to date have been pretty lousy). Yes, of course it will.

Kent Sepkowitz

But exactly how the next chapter of this Covid-19 story plays out is a bit harder to predict. There are some elements of our current public health landscape that make the situation seem pretty grim. In the US, we have a good but not great vaccination rate, mediocre acceptance of boosters and deepening fatigue from the abstemious life of masks and distancing. Plus, the BA.2 subvariant is distinctly more contagious than the first Omicron strain. That’s not to mention the view held by too many that public health interventions such as masking represent a dangerous government overreach.

Put plainly, it is clear the US will not escape the insatiable maw of the BA.2 subvariant. My guess is it will get pretty bumpy in the weeks ahead, though I doubt it will be as bad as the Christmas explosion of Omicron.

The good news is that many people developed immunity from the recent Omicron surge. This, combined with vaccination, has led to a countrywide immunity as high as 73%, according to data from the Institute for Health Metrics and Evaluation, which should act as a bulwark against a repeat of the runaway infection from December and January.

Plus, warm weather may have advantages both on the virus itself (though it has not been much help so far in the pandemic) and on the way people interact. Nice weather brings people outdoors, where wind and open air can blunt viral transmission, even from that person who is coughing uncontrollably.

Unfortunately, though, immunity is short. The immunity against the coronavirus infection provided by disease and vaccine, including the booster, wanes a little every day. That waning immunity proved to be a substantial factor in South Korea, which is experiencing a still-accelerating outbreak with about 430,000 new cases a day in a country of about 52 million.

Although Denmark and then other parts of northern Europe saw the BA.2 subvariant early, the story of South Korea, once the poster child for Covid-19 control, is the most instructive for understanding what may be ahead for the United States.

From the outset, South Korea embraced vaccination, testing, masks, contact tracing and social distancing and successfully kept the pandemic at bay. But recently it has become the victim of its own success, falling into the Western trap of dropping its guard, allowing cases to start back up, then scrambling to put the pieces back into place.

For example, many in South Korea were vaccinated in the first half of 2021, but because things were going so swimmingly, a booster was not strongly recommended, leaving many, particularly older adults, at risk for infection.

South Korea also began to relax its famously rigid mask and distancing precautions in November. In fact, the situation was so good in parts of Asia that the Southeast Asia Covid Tracker “wrapped up” operations on the last day of February, ceding to the “new normal of living with Covid-19.”

These three factors – relaxed precautions, a population with waning immunity and a new very transmissible variant – collectively served to sink the country into the throes of its current frightening outbreak. And these same three factors are at play across the United States.

The high death numbers from South Korea also are important to consider. Omicron has shown itself to have a low case fatality rate; this rate, however, is offset by the overwhelming number of cases – one death in 1,000 cases becomes a big number when 450,000 cases a day are being diagnosed – a phenomenon seen in the US with the first Omicron wave. Characterizing the disease (accurately) as milder than other variants became, for many, synonymous with thinking of the disease as harmless; yet the daily death count from Covid-19 in the US approached that of earlier waves.

All these factors mean the US has no reason to think it will avoid a BA.2 wave with the same risks of severe disease in older people, those with other medical conditions and, as ever, the unvaccinated. After all, 1 out of every 6 Americans over 5 years of age still have not initiated a vaccine series, leaving a large target for a super-contagious virus. And once rekindled, community viral load will increase, reaching a density sufficient to overcome the waning immunity of older adults.

In other words, sooner than later, it will – again – become a story of the unvaccinated and the damage they are inflicting on society by their stubborn refusal to protect their neighbors.

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    So prepare yourself for more of the same: more politics, more pleading from the US Centers for Disease Control and Prevention for people to get serious, more debates about the need for a fourth shot, and more discussion of the impact of the infection and masks on schools, crowds, restaurants and the economy.

    Whatever form the BA.2 subvariant surge takes, mild or not so mild, the problem will be entirely self-inflicted. For the last 14 months, we have had the tools to prevent not the next variant but its impact on individuals and on society. Perhaps the coming wave will be effective at convincing the millions of holdouts by demonstrating – again – that vaccines and masking and all the rest are the only way out from an endless pandemic.