Hundreds more US hospitals are to begin vaccinating their workers on Tuesday as regulators issued a positive review of a second jab.
The Food and Drug Administration (FDA) said its preliminary analysis confirmed the effectiveness and safety of the vaccine developed by Moderna and the National Institutes of Health, bringing it to the cusp of US authorisation.
A panel of outside experts will offer their recommendation on Thursday, with a final FDA decision expected soon thereafter.
It comes as hospitals across the US begin ramping up vaccinations with the jab developed by Pfizer and BioNTech, which the FDA cleared last week.
Packed in dry ice to stay at ultra-frozen temperatures, shipments of the vaccine are set to arrive at 400 additional hospitals and other distribution sites, one day after the nation’s death toll passed 300,000.
The first three million shots are being strictly rationed to frontline health workers and elderly patients, with hundreds of millions more shots needed over the coming months to protect most Americans.
The country’s daily death count continues to top 2,400 amid more than 210,000 new daily cases, based on weekly averages of data compiled by Johns Hopkins University.
The first vaccine deliveries have provided a measure of encouragement to exhausted doctors, nurses and hospital staffers around the country.
Johnnie Peoples, a 43-year-old survival flight nurse, was excited and a little nervous on Monday afternoon as he became the first person to receive the vaccine at the University of Michigan Medical Centre in Ann Arbor.
“Just to be a part of it is a good feeling,’’ he said.
In Florida, government officials expect to have 100,000 doses of the vaccine by Tuesday at five hospitals across the state.
“This is 20,000 doses of hope,” Tampa General Hospital president and chief executive office John Couris said after the delivery of 3,900 vaccine vials on Monday. Each vial has five doses.
Because the vaccine requires two rounds, the people getting injections now will need a second shot in about three weeks.
Vaccinations are also expected to begin on Tuesday in New Jersey, which is dividing some 76,000 doses among health workers and nursing home residents.
The US government is co-ordinating the massive delivery operation by private shipping and distribution companies based on locations chosen by state governors.
After another initial set of deliveries on Wednesday, officials in the Trump administration’s Operation Warp Speed in Washington said they will begin moving 580 more shipments through the weekend.
“We’re starting our drumbeat of continuous execution of vaccine as it is available,” Army General Gustave Perna, chief operating officer for Warp Speed, said on Monday.
“We package and we deliver. It is a constant flow of available vaccine.”
Shots for nursing home residents will not begin in most states until next Monday, when some 1,100 facilities are set to begin vaccinations.
Mr Perna and other US officials reiterated their projection is 20 million Americans will be able to get their first shots by the end of December, and 30 million more in January.
That projection assumes swift authorisation of the Moderna vaccine, which also requires two shots for full protection.
The US government has purchased 100 million doses of the Pfizer vaccine and orders for 200 million doses of the Moderna vaccine.
Assuming no manufacturing or distribution delays, that would be enough to vaccinate 150 million Americans by mid-2021.
Moderna’s vaccine is the same type as Pfizer’s, made with the same technology.
In scrutinising early results of a 30,000-person study, the FDA found it also worked just about the same.
The Moderna vaccine was more than 94% effective overall at preventing Covid-19 illness and 86% effective in people 65 and older.
The FDA uncovered no major safety issues.
Recipients tend to experience temporary flu-like side effects that can include fever, fatigue and aches, especially after the second dose as the vaccine revs up their immune system.
Even such a large study cannot detect very rare problems but the FDA looked carefully for signs of allergic reactions after the UK last week reported some possible reactions among people with a history of severe allergies.
The FDA found no serious allergic reactions in the Moderna study.
About 1.5% of vaccine recipients and 1.1% who got dummy shots reported possible smaller “hypersensitivity” reactions.
Both Moderna’s and Pfizer-BioNTech’s shots are so-called mRNA vaccines.
They are not made with coronavirus itself, meaning there is no chance anyone could catch it from the shots.
Instead, the vaccine contains a piece of genetic code that trains the immune system to recognise the spiked protein on the surface of the virus.
