By Norm Elrod

(CBS Detroit) — Pfizer announced in November that its COVID-19 vaccine has an efficacy rate of 95 percent after the second dose. Recent documents suggest some protection could even come to recipients after the first dose. The Food and Drug Administration (FDA) has confirmed the vaccine’s safety and effectiveness, and it could be approved for use in the United States this week. Pfizer’s FDA hearing is scheduled for Thursday.

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Moderna’s COVID-19 vaccine, also announced last month and also requiring two shots, has a similar level of efficacy. Their FDA hearing is set for next week.

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With two viable vaccines available, most of the U.S. population could be vaccinated by this summer. Vaccinations should start this month, according to Assistant Secretary for Health and Human Services Brett Giroir.

“We will be able to vaccinate about 20 million people this month, and another 20-25 million in January and another 20-25 million in February,” he said on CBS This Morning. “There is strong commitment that we will be able to provide vaccine to any American who wants it by late spring, mid-summer.”

Vaccinating 20 million people in December would require 40 million doses. (Again, Pfizer and Moderna’s COVID vaccines each require two doses.) The companies have committed to providing a total of about 40 million doses by year’s end. Many health officials predict there will be enough doses for the entire U.S. population by June of 2021. (For reference, the U.S. population is approximately 330 million people.) These estimates all assume that the Pfizer and Moderna vaccines are authorized.

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The United Kingdom began its immunization program today, with a 90-year-old grandmother receiving the first dose of the Pfizer vaccine. The start of the U.S. program is imminent. But many questions remain about when people can expect to receive doses of the vaccine.

Here is what we know.

  • The ultimate decision about distribution will be left up to governors in individual states, though most tend to follow guidelines from the Centers for Disease Control and Prevention (CDC).
  • The CDC recommends that initial doses go to the approximately 21 million healthcare professionals in the U.S. and another 3 million to residents at long-term care facilitates, along with accompanying staff.
  • After healthcare workers, priority should also go to essential workers, according to the CDC. These 87 million people generally work outside the home providing necessary goods and services, often connected to infrastructure. That’s a variety of industries, ranging from construction and supply chain support to defense and law enforcement to food and energy.
  • Also high on the priority list are the 100 million or so people with underlying health conditions that put them at high risk of suffering or dying from COVID. The immunocompromised, like those with cancer or HIV, and anyone with a lung disease fall in this category.
  • Older adults over the age of 65 are another high-risk group that will be prioritized. COVID complications increase in severity with age.

If you don’t fall into one of these categories, you likely won’t have access to a vaccine until spring at the earliest. But, as stated above, specific decisions about distribution will fall to the states.

So, Maryland, for example, is splitting distribution into phases. Phase 1A includes health care workers, residents and staff of long-term care facilities and first responders. Phase 1B adds in people at “significantly higher risk” of severe coronavirus illness. Phase 2 is everyone else. The state will receive an initial allocation of 155,000 doses with possibly 300,000 more by the end of the year. The population of Maryland is slightly above 6 million people.

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Minnesota is expecting 183,400 doses total from Pfizer and Moderna by the end of the year. The vaccines will go to key hospitals and hubs across the state, and will be administered with eye toward “protecting life and health of those most susceptible to serious complications and those who care for them,” according to Governor Tim Walz. Minnesota’s population exceeds 5.6 million people.

New York state is set to receive 170,000 doses by next week. New York City could get 480,000 doses by early January. Healthcare and other frontline workers, along with long-term care residents, will receive their vaccines first. But priority is unclear after those people. New York state has close to 20 million people.

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All of these state numbers are estimates from the federal government and could change. Pfizer already cut manufacturing goals from 100 million to 50 million by end of 2020, based on supply chain issues. A report also surfaced yesterday that last summer the Trump administration declined to purchase more than the agreed-upon 100 million doses from Pfizer. The decision reportedly allowed other countries more access to doses and could delay the receipt of additional doses until June of 2021.