July 2 (Reuters) - The U.S. government has awarded $176

million to Moderna ( MRNA ) to advance development of its bird

flu vaccine, the company said on Tuesday, as concerns rise over

a multi-state outbreak of H5N1 virus in dairy cows and

infections of three dairy workers since March.

Funds from the U.S. Biomedical Advanced Research and

Development Authority will be used to complete late-stage

development and testing of a pre-pandemic mRNA-based vaccine

against H5N1 avian influenza.

U.S. officials said on a press call that late-stage testing

would begin in 2025, pending results expected in the coming

weeks of Moderna's ( MRNA ) phase 1 trial. The late-stage trial would

likely focus on safety and immune response.

The contract includes options to accelerate the development

timeline if needed, based on an increase in human cases, the

severity of cases or human-to-human transmission of the virus.

It is too early to tell how many doses Moderna ( MRNA ) will be able

to manufacture, said Robert Johnson, director of the medical

countermeasures program at HHS, on the call.

In March, U.S. officials reported the first outbreak of the

H5N1 virus in dairy cattle, which has since infected more than

130 herds in 12 states.

Scientists are concerned that exposure to the virus in

poultry and dairy operations could increase the risk that the

virus will mutate and gain the ability to spread easily among

people, touching off a pandemic.

The risk to the general public from bird flu remains low,

and vaccination is not currently recommended for any segment of

the population, Dawn O'Connell, assistant secretary for

preparedness and response at the U.S. Department of Health and

Human Services, said on a call with reporters.

However, "robust discussions" are occurring within

government agencies about whether vaccinating farm workers would

be helpful, said Nirav Shah, principal deputy director of the

U.S. Centers for Disease Control and Prevention, adding that no

final decisions have been made.

The government expects to have more announcements on H5N1

vaccines in the near future, O'Connell said. In a previous

briefing, O'Connell said her agency was also negotiating with

Pfizer ( PFE ) for an mRNA vaccine against H5N1.

Both the Moderna ( MRNA ) and Pfizer ( PFE ) vaccines use messenger RNA, the

technology used in their COVID-19 vaccines.

"mRNA vaccine technology offers advantages in efficacy,

speed of development and production, scalability, and

reliability in addressing infectious disease outbreaks, as

demonstrated during the COVID-19 pandemic," Moderna ( MRNA ) CEO Stephane

Bancel said in a statement.

Manufacturing of conventional flu vaccines using cell or

egg-based technology can take four to six months.

U.S. officials previously announced they were moving bulk

vaccine from CSL Seqirus that closely matches the

current virus into finished shots that could provide 4.8 million

doses if needed.

Some of those doses could be available as early as this

month, O'Connell said. Those shots could potentially be used to

inoculate farm workers and others at risk of exposure to the

virus.

Lab experiments from the U.S. Food and Drug Administration

continue to confirm that pasteurization inactivates the bird flu

virus in dairy products, said Don Prater, director of the

agency's Center for Food Safety and Applied Nutrition.

The FDA is conducting ongoing tests of retail dairy products

for traces of avian flu and has cautioned against consuming raw

milk.