CNN  — 

The US will have to work “double time” to make up for Covid-19 vaccination delays this week caused by the winter weather that has ravaged much of the country, according to Dr. Anthony Fauci.

“It’s been slowed down in some places going to a grinding halt,” Fauci, the nation’s top infectious disease expert, said in an interview with MSNBC Thursday.

“We’re just going to have to make up for it as soon as the weather lifts a bit, the ice melts and we can get the trucks out, and the people out and getting the vaccine into people’s arms,” he said. “We’re going to just have to make up for it, namely do double time when this thing clears up.”

A number of states have reported delays in vaccine deliveries and distribution, forcing providers to cancel or reschedule appointments for vaccinations. The Federal Emergency Management Agency (FEMA) on Thursday said more than 2,000 vaccine sites are in areas suffering from power outages.

In some cases, the delays have resulted in providers having to cancel appointments, even as federal and state officials have worked to boost vaccination numbers by adding more vaccinators to their rosters, launching vaccine events, opening mass vaccination sites and creating partnerships with companies and pharmacies.

Houston, hit with both power outages and water problems during the storm, plans to resume giving vaccinations Saturday and Sunday, the city’s health department said in a release Thursday.

Fortunately, the second dose of the two-dose vaccines from Pfizer/BioNTech and Moderna can be administered up to 6 weeks after the first, according to the US Centers for Disease Control and Prevention.

The second doses of the Pfizer and Moderna vaccines were recommended to be administered 21 days and 28 days after the first, respectively. So, if your appointment to receive a second dose was canceled due to weather, don’t panic. There’s still time.

Both UPS and FedEx have told CNN they’re working to get vaccines delivered.

UPS says it has “extensive contingency plans” in place to complete vaccine deliveries, despite the winter storm. Spokesperson Glenn Zaccara told CNN the company was in “regular and frequent contact” with federal agencies and vaccine manufacturers, with talks occurring “often hourly.”

Meantime, FedEx said it’s prioritizing coronavirus vaccine deliveries, and it’s working with the parties waiting on shipments. But “prolonged severe weather is continuing to impact much of the FedEx network.”

Here’s how many people have been vaccinated

More than 41 million people so far have received at least their first dose of a Covid-19 vaccine, according to CDC data, while more than 16 million have been fully vaccinated with two doses.

On Tuesday, President Joe Biden said 600 million Covid-19 vaccine doses would be available to the country by the end of July, “enough to vaccinate every single American.”

His promise echoes earlier announcements that the US was on track to have enough vaccines for 300 million Americans by the end of July.

Actually vaccinating all those people will likely take longer, per Fauci. He told CNN, “It may take an additional couple of months actually, maybe toward the end of the summer, to get everybody vaccinated.”

A customer wears a face mask while shopping for flowers on February 12, 2021 in Los Angeles, California

Work also continues toward making vaccines available to younger patients.

Pfizer/BioNTech’s vaccine has been granted emergency use authorization by the US Food and Drug Administration for people age 16 and older, but the companies expect to start Covid-19 vaccine studies for children between the ages of 5 and 11 in the next couple months, according to a news release.

Additionally, the companies say they have plans to study the vaccine in children younger than 5 later this year.

An ongoing trial for children ages 12 to 15 is fully enrolled, and the companies say data could be submitted to regulatory authorities in the second quarter of 2021.

Researchers found higher rate of infection in pregnant women

Researchers of a study released Tuesday suggested that pregnant people should be prioritized for vaccination after they found that the Covid-19 infection rate among expectant women in Washington state was 70% higher than in adults of similar age in the state.

The infection rate in pregnant women in the study was 13.9 out of every 1,000 deliveries, compared to an overall rate of 7.3 out of 1,000 for 20 to 39-year-olds in the state.

The higher infection rates “may be due to the overrepresentation of women in many professions and industries considered essential during the COVID-19 pandemic — including healthcare, education, service sectors,” lead author Dr. Erica Lokken said in a news release.

“Pregnant women are written out of the allocation prioritization in about half of U.S. States. Many states are not even linking their COVID-19 vaccine allocation plans with the high-risk medical conditions listed by the [Centers for Disease Control and Prevention] —which include pregnancy,” Waldorf said.

Black and Hispanic people are getting fewer vaccinations than White people in most states

Kaiser Family Foundation (KFF) researchers analyzed state level data for the 34 states that collect demographic information on Covid-19 vaccinations as of February 16.

In most of those states, Black and Hispanic people have received smaller shares of vaccinations compared to their shares of cases, deaths and percentage of the population, the researchers note. The opposite is true for White people in most states.

In Texas, for example, Hispanic people account for 42% of coronavirus cases, 47% of Covid-19 deaths and 40% of the state’s population – but they have gotten just 20% of vaccinations.

Among 27 states that report ethnicity data for those who have received at least one dose of the vaccine, White people have been vaccinated at a rate three times higher than Hispanic people and twice as high as Black people.

The KFF team noted that some states don’t record the race or ethnicity of those vaccinated.

US has 2 tools to fight variants

It’s more important than ever for Americans to continue practicing safety measures that work against the spread of the virus, health officials said Wednesday, especially as Covid-19 variants threaten to undo the progress made so far.

“The continued spread of variants that are more transmissible could jeopardize the progress we have made in the last month if we let our guard down,” CDC Director Dr. Rochelle Walensky said during a White House briefing.

But by lowering the number of cases, the US will give “fewer opportunities for the variants to spread and fewer opportunities for new variants to emerge,” she added.

It’s a warning that’s been repeated by multiple experts recently as the country’s tally of variant cases keeps climbing while more state leaders are opting to loosen Covid-19 restrictions.

Among the most concerning strains is the highly contagious B.1.1.7 variant, first identified in the UK, that the CDC has previously warned could become “the predominant variant in March.” The agency has reported more than 1,270 cases of the variant across 41 states and Washington, DC.

But Fauci told CNN Wednesday night that the US has two powerful tools that can help against its spread and move the country further out of the pandemic’s tunnel.

“The two ways that we can counter that is one, continue to do the kinds of public health interventions that we talk about all the time,” he said, like the universal wearing of masks, social distancing, staying away from crowded areas and regular hand washing.

“But also, as the weeks and months go by, as you vaccinate more and more people, you have a vaccine that works against this variant,” Fauci added.

Lab studies offered encouraging news this week, suggesting the Pfizer and Moderna vaccines can protect against Covid-19 variants.

“So if we roll out the vaccine … and get as many people vaccinated as quickly as we possibly can while we maintain the public health measures, we should be in good stead,” Fauci said.

It won’t be easy, he cautioned, because of the variant’s transmissibility – which is why “we have to act quickly on that,” Fauci said.

CDC director warns against travel

Meanwhile, amid the repeated warnings for Americans to continue taking safety measures, the CDC director also urged the American public to avoid travel, even domestically.

“Don’t travel,” Walensky said during a JAMA livestream Wednesday, highlighting the advice is especially important because of the circulation of variants. “We really, really would advocate for not traveling right now.”

Asked about whether there would be any guidance from the CDC about Covid-19 testing prior to domestic flights, Walensky said the US does not kind of tests that would make that possible.

“You shouldn’t be traveling anyway,” she said.

But the US has recently seen some of its busiest air travel days since the holidays.

The TSA reported it screened more than 967,000 people at airports on Monday and a further 738,000 people on Tuesday.

“If you choose to travel, please wear a mask,” TSA spokesperson Lisa Farbstein reminded travelers in a tweet.

CNN’s Michael Nedelman, Pete Muntean, Andrea Diaz, Rebekah Riess, Andrea Diaz, Amanda Sealy, John Bonifield and Lauren Mascarenhas contributed to this report.