As the U.S. prepares to roll out a COVID-19 vaccine, officials warned Thursday that hackers were targeting companies essential to the plan.

In a blog post released Thursday, IBM said it had uncovered a phishing plot targeting “organizations associated with a COVID-19 cold chain,” referring to the chain of people and businesses responsible for storing the vaccine at the necessary cold temperatures.

The U.S. Cybersecurity and Infrastructure Security Agency shared the report Thursday along with a warning to anyone involved in operations related to the vaccine.

“The Cybersecurity and Infrastructure Security Agency (CISA) encourages Operation Warp Speed (OWS) organizations and organizations involved in vaccine storage and transport to review the IBM X-Force report,” its post read.

Earlier this week, advisers with the U.S. Centers for Disease Control and Prevention (CDC) determined that health care workers and nursing home residents should be the first Americans to receive the vaccine.

News of the phishing plot came as the U.S. was battling its most severe and widespread surge of COVID-19 infections. According to data from the Johns Hopkins Coronavirus Resource Center, more than 3,100 Americans died of COVID-19 Wednesday, by far the highest one-day number of deaths since the pandemic began.

California Governor Gavin Newsom announced a statewide ban on gatherings and “nonessential activities” Thursday. The state has thus far recorded 1.3 million confirmed cases and 19,400 deaths from the virus.

The CDC warned Wednesday of a bleak winter ahead as the country continues to see nationwide surges of COVID-19 cases.

"The reality is that December, January and February are going to be rough times," CDC Director Robert Redfield said in a livestream presentation hosted by the U.S. Chamber of Commerce Foundation. "I actually believe they're going to be the most difficult time in the public health history of this nation."

The U.S. topped 100,000 hospitalizations for the virus Wednesday for the first time since the pandemic began, according to the COVID Tracking Project.

While many Americans have grown weary of following social-distancing and mask-wearing guidelines, Redfield urged people to adhere to these practices in the coming months.

Millions of Americans traveled for the Thanksgiving holiday last week, despite advice from health experts against flying and gathering in large groups indoors.

Also on Wednesday, the CDC said Americans should quarantine for 10 days after potential exposure to the virus, shortening the previous guideline of a 14-day quarantine.

The United States has recorded more than 276,000 deaths and more than 14.1 million confirmed cases of the coronavirus this year, according to the Johns Hopkins University Coronavirus Resource Center. (Text, excluding headline, courtesy VOA)

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