NEW YORK (CBSNewYork) — Just when much of the country has started to open up, there is alarming evidence of a new spike in the coronavirus pandemic.

As CBS2’s Dr. Max Gomez reported Wednesday, experts say it’s likely due to the highly contagious Delta variant of the COVID-19 virus.

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COVID VACCINE

The reason public health experts are concerned about the variant is because it spreads more efficiently than the other coronavirus strains we’ve seen so far.

“It is well over 90% of the isolates in U.K. are this Delta variant, which is causing them a considerable problem. Right now, it’s 20.6% in the United States and doubles about every two weeks,” Dr. Anthony Fauci said on CBS This Morning.

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Worse yet, data from the United Kingdom shows that Delta makes you more seriously ill. That combination of greater transmissibility and severity of disease has led to the new variant accounting for nearly half of all COVID-19 cases across 10 states.

“It will be the dominant strain among those areas, those regions, of the country where the vaccination rate is lower than we would like. The easiest way to stop this is to get vaccinated because, fortunately for us, the vaccine works quite well against it,” Fauci said.

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One way to gauge that the present vaccines do protect against the Delta variant is to look at who’s getting hospitalized with COVID. At Cox Medical Center in Missouri, roughly 90% of COVID cases are Delta and, according to Cox President and CEO Steve Edwards, “Virtually every single patient in the hospital with COVID is not completely vaccinated.”

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As for children, they’re not necessarily more susceptible to Delta, but because it is more transmissible and kids under 12 still can’t get vaccinated, they may be more likely to get infected with the Delta variant than the original Alpha version. Again, the lesson here is, vaccines work.

Dr. Max Gomez