'We're gonna lose a bunch more people,' GOP governor says while pleading for residents to get vaccinated

"We're gonna lose a bunch more people, West Virginia, no question about that," said Gov. Jim Justice said Wednesday.

The number of Covid-19 patients in ICUs just reached an all-time high -- 298, the governor said.

"All I can possibly do, with a good conscience, is continue to urge you, in every way, to get vaccinated," he said.

Many doctors are doubling down on pleas for Americans to get vaccinated -- especially as the flu season could lead to simultaneous infections of the Delta variant and the flu.

And that could be disastrous not just for a person's immune system, but also for overwhelmed hospitals.

"We've been too complacent about the spread of respiratory diseases in the wintertime," former US Food and Drug Administration (FDA) Commissioner Dr. Scott Gottlieb said.

"With a twin threat of flu and Covid circulating, we're not going to be able to enjoy that complacency anymore," he said. "I think we're going to have to readjust how we live our lives."

He said that could include optional mask-wearing in the winter or improved air filtration in schools and workplaces.

But there's also some good news in the fight against Covid-19.

Booster shot side effects are well tolerated, study says

As more eligible Americans get a third dose of Covid-19 vaccine, new data shows "the frequency and type of side effects were similar to those seen after the second vaccine doses and were mostly mild or moderate and short-lived," said Dr. Rochelle Walensky, director of the US Centers for Disease Control and Prevention.

The most common complaints were injection site pain (71%), fatigue (56%) and a headache (43.4%).

Booster doses of the Pfizer/BioNTech vaccine are now available for people who received the vaccine at least six months ago and are age 65 and older; adults with a medical condition that puts them at high risk for severe illness from Covid-19; and adults who live or work in a setting that puts them at high risk of exposure to coronavirus.

Health experts are also looking into whether those who originally got the Moderna or Johnson & Johnson vaccine can get Pfizer boosters before the companies release their own, said Dr. Anthony Fauci, director of the National Institutes of Allergy and Infectious Diseases.

Data evaluating the safety and efficacy of mixing different brands of vaccines is coming soon and will be submitted to the FDA for review, Fauci said Tuesday.

Child Covid-19 cases climb as parents wait for a vaccine

This week, the American Academy of Pediatrics reported 206,864 new Covid-19 cases among children during the week ending September 23. That accounted for 27% of all cases reported nationwide.

Pfizer and BioNTech said Tuesday they have submitted Covid-19 vaccine trial data for children ages 5 to 11 to the FDA for initial review. But they have not formally submitted a request for an emergency use authorization.

"This is sort of typical of a rolling submission, where you submit the data that's available," said Gottlieb, who is now a Pfizer board member.

Once all the data is submitted, Pfizer will ask the FDA for emergency use authorization. Gottlieb said he believes that will happen "imminently."

When the FDA does give the green light, the US will have the capacity to vaccinate younger kids, US Surgeon General Dr. Vivek Murthy said Tuesday.

"The FDA's top priority is getting Covid vaccines for the population, particularly for our children," he said.

But parents are split on whether they would vaccinate children in that age group.

An Axios-Ipsos poll published Tuesday showed 44% of parents of 5-to-11-year-olds would likely vaccinate their children, while 42% said they likely won't.

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