Why is the Covid-19 vaccine more scarce than the flu vaccine?

Simply put, there are fewer manufacturers and distributors of the Covid-19 vaccine. It must be frozen at ultra-cold temperatures, which makes it difficult to ship and store. Full vaccination requires two vaccines, compared to one for the flu. And because the serum is completely new, health care providers should give extra time to monitor patients for possible adverse reactions.

All of this should be documented to ensure that the scarce vaccine is not wasted; allergic reactions are captured; and the second doses, which must be administered within a specified time, are executed correctly.

“The challenge is for state health departments to have exquisite control of doses as they go into arms,” said Litjen Tan, chief strategy officer of the Immunization Action Coalition, an organization that distributes information on vaccines in cabbage. Collaboration with the Centers for Disease Control and Prevention. . “With the flu vaccine, you get it and you go.”

Currently, only Pfizer and Moderna manufacture Covid-19 vaccines available in the US, although versions from other manufacturers, including Johnson & Johnson and AstraZeneca,

are planned.

In comparison, at least four large companies make flu vaccines, which are delivered directly to healthcare providers by three major distributors and several smaller ones.

Only one dealer, McKesson Corp.

, delivers Modern Covid-19 vaccine to federal government. Because the Pfizer vaccine has to be frozen at more extreme temperatures, the company sends it in special thermal shipments and works directly with FedEx and United Parcel Service to move it.

“There are pros and cons to having a single distributor,” said Josh Michaud, associate director of global health policy at the Kaiser Family Foundation, a nonprofit organization focused on health issues. “It’s easier for the government to work with a company. They don’t juggle multiple contracts and contact points. “

When the distribution of the Covid-19 vaccine increases, there will be “a powerful argument” to expand the number of distributors, he said. “McKesson is great, but is he able to reach every corner of every state? Others maintain relationships with offices and medical establishments.

Manufacturers of influenza vaccines also have an initial advantage.

Because the mechanisms for manufacturing and distributing the flu vaccine are well established, health care providers can order shots in January or February that will be administered in the fall and winter. Production begins between six and nine months before distribution, which is completed in phases over a period of about four months. Distribution this season began in August.

Instead, the first Covid-19 vaccine was authorized for emergency use by the Food and Drug Administration on December 11 and distribution began on December 14. .

“It’s more of a timely management strategy,” said Crystal Tubbs, associate director of pharmacy at Ohio State University’s Wexner Medical Center, which administers about 2,000 Covid-19 vaccines a day. “They tell us five or seven days in advance how many vaccines we’ll get next week. Then we schedule appointments.”

The flu vaccine can be refrigerated, while the Covid-19 vaccine should be stored at extremely cold temperatures.

Moderna vials contain 10 doses of vaccine and should be frozen at less than 4 degrees Fahrenheit. Pfizer vials contain five or six doses and should be frozen at less than 94 degrees Fahrenheit.

“We’re talking brutal cold,” Dr. Tan said. “This does not mean that it cannot be done, but we must stop. We need to be more deliberate and thoughtful. “

After puncturing the vials, all doses should be used within six hours or discarded.

When someone is vaccinated, they should be monitored for 15 minutes or, if they have a history of allergic reaction, for 30 minutes, to make sure they do not react badly.

Vaccination is not completed until a second dose is given and the final vaccine must be given within 21 days for the Pfizer vaccine and within 28 days for the Moderna product.

Because the Covid-19 vaccine is being given to a population without previous resistance to the deadly disease, the goal is to inoculate as many people as possible.

“With the flu vaccine, about 50%, or maybe a little more, of the American population is vaccinated in a season,” Dr. Michaud said. “With the Covid vaccine, the ultimate goal is to achieve a level of vaccination against the immunity of the herd. Nobody knows exactly what this is, but at least it is 70% ”.

So far, the US is not even close.

Of the 55.9 million doses of Covid-19 distributed as of Thursday, only 33.9 million have been administered, according to the CDC.

This includes 27.2 million people, or less than 10% of the population, who have received at least one shot and 6.4 million, or about 2%, who are fully immunized.

The agency also estimates that 83.1 million people, or about 25% of the country, have been infected with Covid-19, although it is unclear how long their immunity can last.

In the meantime, enough flu vaccine has been distributed to inoculate more than 58% of the population and, according to the survey results, 53% of all adults have obtained it.

Write to Jo Craven McGinty to [email protected]