Dr. Anthony Fauci has expressed alarm, not just about the annual Sturgis motorcycle festival now taking place in South Dakota - which became a superspreader event last year - but also about additional viral mutations that might be more deadly than the Delta variant.

On Sunday, Fauci stated that more Americans need to get the COVID-19 vaccination because the fatal virus might evolve into a new strain that is even more dangerous than the highly contagious Delta variant that has resulted in new cases, hospitalizations, and deaths among the country's unprotected.

COVID-19 might evolve stronger than the Delta variant

The pandemic is most severely affecting unvaccinated Americans, according to Dr. Anthony Fauci, the country's top infectious disease expert and President Joe Biden's chief medical adviser, who told NBC News' "Meet the Press" that the vaccines remain effective against COVID-19 and all its variants, including Delta, effectively protecting almost all vaccinated individuals from severe symptomatic cases that would require treatment in a hospital.

However, vaccinated persons can get breakthrough cases, and even if they have a moderate case, they can still spread the virus while sick, Mass Live reported. Because of the contagiousness of the Delta variant, public health experts have decided to reintroduce indoor masking guidelines in high-risk locations, regardless of vaccination status.

Per The Independent, at least 700,000 people are anticipated to attend the Sturgis Motorcycle Rally. Only around 150,000 people attended last year, a quarter of the typical turnout, yet hundreds of people were infected and returned to their homes throughout the country.

In connection with the event, South Dakota officials are seeking to boost vaccination awareness, although only around 46 percent of residents in the host county have been vaccinated, compared to a national average of 60.6 percent. Authorities have also attempted to decrease danger by permitting the use of alcohol in public places to keep people outside.

Even as the Delta variant ravages the US with a particular ferocity - particularly in the Southern states, where vaccine resistance remains high, fueled in part by some governors' unwillingness to impose school mask regulations - it might grow worse, according to Fauci.

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Fauci hopes Pfizer will get full approval

Fauci expressed optimism that the Food and Drug Administration will provide complete clearance to the coronavirus vaccine by the end of the month, predicting that the decision would lead to a wave of vaccination requirements in the private sector as well as schools and institutions. The FDA has only given Pfizer, Moderna, and Johnson & Johnson vaccines emergency use permission, but the agency is likely to award Pfizer full approval soon.

Although the Biden administration has indicated that vaccines would not be mandated outside of the federal workforce, it is increasingly encouraging state and local governments, as well as companies, to explore such requirements. President Joe Biden's senior medical advisor, Dr. Anthony Fauci, said "mandates at the local level" are needed to help stop the virus from spreading.

As the Delta variant spreads over most of the United States, Fauci's statements come as the Biden administration considers what levers it might pull to induce more unvaccinated Americans to get their vaccinations.

Biden recently signed regulations forcing government employees to provide proof of vaccination or face random testing, as well as mask requirements and travel limitations. Biden is also awaiting a formal recommendation from Defense Secretary Lloyd Austin on whether or not US troops should be required to get vaccinated, as per NBC New York.

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