(WXYZ) — Hundreds of millions of Americans have rolled up their sleeves for the COVID-19 vaccine.
About half of the people who are eligible are vaccinated in the U.S., but that number is much lower in some places. In those places, the more contagious Delta variant is spreading.
Related: Pfizer vaccine protection takes a hit as Delta variant spreads, Israeli government says
There is also concern that the first two doses won't protect against new, more aggressive variants.
On Monday, Pfizer briefed government officials about the potential need for a booster shot.
This week marks seven months since the first American outside of a trial got the COVID-19 vaccine. Now, people are maskless, venues are at full capacity, and life in Michigan almost feels normal again. But, the coronavirus is changing.
Related: Fast-spreading Delta variant accounts for 1 in 5 current COVID-19 cases in U.S.
"The CDC announced that the Delta variant is over 15 percent of the cases that we are seeing in the US, and that’s bad news," Dr. Anu Malani, the Infection Prevention Medical Director at St. Joseph Mercy Health System, said.
"Delta has been a game-changer. We know what it did in India. It devastated the country the health system collapsed under it," Dr. Matthew Sims, an infectious disease specialist at Beaumont Health System, added.
The Delta variant is in Michigan, but how worried should we be?
"We are seeing some localized outbreaks in communities and areas that have low vaccine rates," Malani said.
As of July 9, 54 people in Michigan have been diagnosed with the Delta variant, according to the state health department.
Over a four-week stretch in Michigan ending on June 22
- 90.5% of specimens were Alpha (B.1.1.7)
- 0.4% were Beta (B.1.351)
- 2.4% were Epsilon (B.1.427, B.1.429)
- 2.1% were Gamma (P.1)
- 0.98% were Delta (B.1.617.2)
"We know with the variants there is less room for error, so for those that need to undergo two vaccines, we want to make sure they get that second dose," Malani said.
But What about a third dose? On Monday, Pfizer spoke before government officials about its booster vaccine hoping for emergency use authorization.
Officials said the third shot could increase antibodies up to ten times more than the second shot.
Last week the FDA and CDC said a vaccine booster isn’t needed right now, and some experts agree
"It would be nice to have work done on this looking at for example how well someone who is boosted is protected versus someone who is not boosted that would be helpful," Dr. Arnold Monto, an epidemiologist at the University of Michigan, said.
Monto says leaders aren’t all on the same page
According to Monto, the main question is what the goals of the vaccination are. Is it to eliminate COVID-19 like Smallpox, or is it to reduce the risk of severe illness like the flu vaccine
"It would be far better right now to get a larger proportion of our population vaccinated which will give very good protection," Monto said.
According to state COVID-19 modeling data, more than 99% of those hospitalized for COVID-19-like symptoms were not fully vaccinated.
From January to mid-June, of the more than 50,000 hospitalizations, just 447 were people fully vaccinated two weeks out from their final dose.
Less than half of Michigan’s eligible population is fully vaccinated and the vaccination rate has plateaued.
For those who are vaccinated, Pfizer says a booster shot could increase their immunity even more.
"There was some implication in what Pfizer said that they are seeing the actual level of antibody drop off but I haven’t seen that published anywhere," Sims said.
Health authorities in Sydney, Australia – a city currently under lockdown because of its Delta outbreak – said Saturday that so far, no one who has received two doses of a vaccine needed to be hospitalized.
Last week, Israel released data showing vaccine effectiveness against the Delta variant declined from more than 90% to about 64%.
Eventually - the Johnson and Johnson, Moderna and Pfizer shots will likely wear off for the roughly half of Americans vaccinated.
"It will continue to exist continue to evolve and we’ll be able to control it with booster shots but probable in a much longer interval than 6 months after the first shot that really would be logistically very difficult," Mondo said.
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