Editor’s Note: Kent Sepkowitz is a physician and infection control expert at Memorial Sloan Kettering Cancer Center in New York. The views expressed in this commentary are his own. View more opinion on CNN. This piece has been updated to reflect the latest news.

CNN  — 

The Omicron coronavirus variant is now spreading at warp speed. It has become the dominant coronavirus strain, accounting for 59% of all new cases as of Christmas Day, according to data from the US Centers for Disease Control and Prevention.

Kent Sepkowitz

Data that has been collected in South Africa, where scientists first discovered this variant from samples collected on November 12, and the UK, where the variant was detected on November 27, is providing us with a sense of what to expect: exponentially rising Covid case counts placing yet another strain on already beleaguered health care systems, post-holiday disappointments and, for those caught in the surge, fevers, aches and other Covid-19 symptoms. Thankfully, most reports so far demonstrate that Omicron infection, relative to Delta or other variants, causes a less severe infection, with a lower hospitalization and case fatality rate.

As information accrues, attention is turning back to where it always seems to land: vaccination. However, this time, it is not only about the unvaccinated – though they remain at high risk for infection. Rather, the focus is on the high rate of vaccine evasion demonstrated by Omicron among recipients of the recommended two-shot series of mRNA vaccines (Moderna or Pfizer/BioNTech).

In the last few weeks, reacting both to Omicron and clear evidence of fading immunity to the Delta variant after six months, public health authorities strongly encouraged already vaccinated individuals 16 and older to receive a third dose – the booster – pronto. On Monday, the US Food and Drug Administration expanded booster eligibility to 12 to 15 year olds, while shortening the interim period between the second dose and booster dose to five months for all eligible individuals.

Adding the third shot clearly is effective against Omicron as well, with National Institutes of Health data on the Pfizer vaccine showing that protection after three doses can reach about 80% effectiveness. Preliminary data from Imperial College London on both mRNA vaccines used in the US places the protection from a third dose between 55% and 80%.

As former NIH director Francis Collins and UK leaders noted, booster-induced immunity is also critical for reducing the risk of severe symptoms, even if a breakthrough infection should occur.

All this scrambling to come up with the best approach has created a great deal of uncertainty. Vaccine and public health experts, however, have been through this sort of adjustment in mid-air many times before. In 2009, for example, facing the H1N1 influenza pandemic, experts decided to add an additional, newly constituted vaccine to the routine seasonal influenza shot. Owing to the arduous, multi-month production time required for influenza vaccines, the remedy – a new vaccine using the same old technology – was not available until much of the pandemic had passed.

At other points, experts have determined that an additional shot of an already available vaccine (aka a “boost”) was recommended to subdue an observed rise in “breakthrough” cases: vaccine programs to prevent measles, mumps and rubella, among other infections, have been adjusted to include an additional shot after a sustained uptick in cases among the already vaccinated was observed.

Plus, the notion of giving a vaccine three or even four times to kickstart initial immunity is quite familiar for public health officials. An example of this is the remarkably successful US program to curb hepatitis B with a comprehensive three-vaccine series. For some people who have a sluggish initial response (5% to 15% of the overall population), a second round of three shots – six vaccines in all – is required to confer immunity.

This was all done soberly, quietly and without public protest or intimidation. It also was done without each “breakthrough” infection being viewed as calamitous or clear evidence of vaccine program failure due to bad judgment and false promises or political hocus pocus and Big Pharma greed.

So where does all of this leave us? Clearly, everyone eligible must receive a booster and, long-term or until a new group of vaccines demonstrates otherwise, the standard Covid-19 vaccine schedule must be a three-vaccine series for everyone, with the possibility of additional vaccinations if the data demonstrates the need. In short, we need to have a flexible mindset about what constitutes the “primary vaccine series” and be open to the possibility that, as with so many other infections, we may need to periodically top up our immunity. In this regard, it should be noted that Israel, which led the call for a third vaccine, has now begun to administer a fourth after seeing breakthroughs months after the third vaccine.

The months ahead will be scary as we will inevitably watch Covid cases rise, but they will also be exciting on the vaccine front. For example, a very futuristic-sounding new class of vaccine that uses recombinant nanoparticle technology to present a bit of Covid-19 spike protein to the body’s immune system has just received World Health Organization (WHO) emergency use listing (EUL), a prerequisite for distributing the vaccine to nations under the COVAX program.

For now, though, the basics are these: For triply vaccinated persons, the appearance of Omicron just as Christmas and New Year’s celebrations were about to begin was extremely discouraging but health-wise, it may have been miserable, but surely was not a catastrophe.

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    For unvaccinated persons – well, here we go again. As President Joe Biden has grimly and accurately forecast, given our current understanding of Omicron, those without immunity can anticipate a “winter of severe illness and death.” Perhaps the Omicron surge will accomplish what the Alpha and Delta surges before it failed to do: convince people to protect their own and their community’s health. Hope springs eternal.

    Finally, the sudden appearance of the rampaging Omicron variant might finally teach us all that the when and how and where of the next Covid-19 variant simply can’t be predicted. For our New Year’s resolution, perhaps we should all simply stop trying.