US biotech firm Moderna said Wednesday it had dosed its first participants in a human study of an mRNA vaccine that targets multiple strains of influenza.

The company intends to recruit 180 adults in the United States for the Phase 1/2 portion of the trial to evaluate the safety and strength of immune response to the shot, called mRNA-1010.

It is based on the same messenger ribonucleic (mRNA) technology deployed in Moderna's Covid-19 shot, which is more than 90 percent effective, and if the trial proves successful, it could lead to a new generation of more protective flu vaccines.

"We expect that our seasonal influenza vaccine candidates will be an important component of our future combination respiratory vaccines," said CEO Stephane Bancel in a statement.

The majority of current flu vaccines are based on inactivated viruses cultivated in chicken eggs.

The strains have to be selected six to nine months before the vaccines are intended to be used, and their efficacy is approximately 40 to 60 percent.

Moderna hopes mRNA technology, which provokes an immune response by delivering genetic molecules containing the code for key parts of a pathogen into human cells, can accelerate development and increase scalability.

Several mRNA molecules that encode for different strains can also be delivered in the same shot.

The flu shot under development targets four strains of flu recommended by the World Health Organization (WHO): A (H1N1), A(H3N2), B/Yamagata and B/Victoria.

The WHO estimates there are approximately three to five million severe cases of flu each year globally and 290,000 to 650,000 flu-related respiratory deaths.

Moderna also plans to explore potential combination vaccines against flu, SARS-CoV-2, respiratory syncytial virus (RSV) and human metapneumovirus (hMPV).

Pentagon considering mandatory COVID-19 vaccines
 Washington DC (UPI) Jul 7, 2021 –

Preliminary discussions have begun on making COVID-19 vaccines mandatory for all U.S. troops, Pentagon spokesman John Kirby said.

While he noted that the vaccine is currently optional and administered under the U.S. Food and Drug Administration's Emergency Use Authorization, full FDA approval could mean making the vaccine mandatory.

"Should the FDA approve it, then I am certain that Pentagon leadership will take a look at what our options are going forward, including the potential option of making mandatory," Kirby told a press briefing on Tuesday.

"It [the vaccine] is not FDA-approved and therefore it is still a voluntary vaccine," he added. "I would like to add that as we speak almost 69 percent of DoD personnel have received at least one dose. That's not bad."

Last week, the website Army Times reported that the U.S. Army has directed commands to prepare to administer mandatory COVID-19 vaccines beginning on Sept. 1, pending an expected full FDA approval.

The directive was an executive order by Department of the Army Headquarters.

In May, manufacturers Pfizer and BioNTech requested full approval of their vaccines by the FDA, with manufacturer Moderna seeking similar approval on June 1.

While the FDA has not responded, a May survey of civilians by the Kaiser Family Foundation indicated that one-third of unvaccinated adults would be more likely to obtain the vaccine if it is fully approved.

Over 930,000 U.S. service members have been fully vaccinated thus far.

Over 300,000 service members, dependents, civilian workers and contractors have been infected, leading to 357 deaths, a Defense Department update on Wednesday said.