Scientists believe one variant called COH.20G/501Y could be more infectious than past forms of the coronavirus.
The study took place in Israel, which is currently leading the world in terms of vaccinating its population.
The man spent 22 days in hospital following the incident.
Some hospitals in South Carolina were reported to be confused over who is eligible and who to prioritize for vaccination.
The Food and Drug Administration recalled the frozen treats made by Weis Markets over concerns the products could be "contaminated with extraneous material, specifically metal filling equipment parts."
"We fear this mutation might have an impact, and what we don't know is the extent of the impact," said researcher Penny Moore.
"These families should not be going through this. No family should be going through this," said Sara Sidner on a Tuesday episode of 'New Day.'
The latest bust comes as total confirmed COVID-19 cases in Los Angeles County approach 940,000.
The state is ramping up the roll-out of vaccines as it struggles to contain the virus.
Among those who have received their first dose are nearly 700,000 high-risk people in long-term care facilities.
Scientists say it is currently unclear whether or not the new variant is more transmissible and if vaccines will be less effective against it.
"On Wednesday, January 6, many members of the House community were in protective isolation in a room located in a large committee hearing space... During this time, individuals may have been exposed to another occupant with coronavirus infection," said Dr. Brian P. Monahan.
Maximum protection from the Pfizer-BioNtech vaccine—as well as long-lasting immunity—is only reached seven or more days after the second dose.
As the U.S. struggles to contain the virus, a new, more infectious U.K. variant is now in eight states, and another from South Africa is believed to be spreading undetected.
The variant appears to be significantly more transmissible than the original, although it does not seem to cause more severe illness.
Fauci's comments come as the U.S. reported more than 4,000 COVID-19 deaths on Thursday—a new daily record for the pandemic.
A handful of states in the Midwest, Northeast and the southwest reported the highest number of coronavirus deaths per 100,000 people.
The number of hospital beds needed across the country is projected to peak in just over a week, according to the Institute for Health Metrics and Evaluation.
America's top infectious disease specialist and incoming chief medical advisor to the Biden administration made the assertion as the U.S. struggles with vaccine roll-out setbacks.
The new, more infectious variant has been detected in California, Florida, New York, and Georgia. Fauci told Newsweek he would be "very surprised" if it was not in "several more states."
North and South Dakota are among the states that have administered the most number of vaccinations in the country so far.
America's top infectious disease expert told Newsweek that although the 501.V2 virus has not yet been detected, "sooner or later it will get here."