An Australian-led study has found the majority of women who get bird flu while pregnant will die along with the unborn baby.

Scientists reviewed more than 1,500 papers that looked into 30 reported cases of bird flu in pregnant women from four countries.

Following the study, the MCRI is now calling for more awareness to be raised on the "vulnerability of pregnant women to a new pandemic."

Professor Jim Buttery said vulnerable populations were often at high risk of developing severe disease and death during pandemics.

"Pregnant women have experienced high death and critical illness rates during the influenza and SARS-CoV-2 [COVID-19] pandemics and the Ebola epidemic," he said.

Buttery said ethical pandemic preparing to avoid preventable deaths required early inclusion of vulnerable populations in vaccine development, monitoring and trials.

"A pregnancy-focused research agenda should be developed and facilitated by medical review boards, regulators and policy makers," he said.

Researcher Rachael Purcell said it was a priority to include pregnant women in pandemic planning as early as possible.

"Increasing numbers of human cases of avian influenza associated with outbreaks in birds and mammals raises concerns about the possibility of another pandemic in the near future," she said.

"Despite being a high-risk population, pregnant women are often excluded from vaccine trials, priority access to therapeutics and delayed entry into public health vaccination programs.

Purcell said a paradigm shift was required to regularly include pregnant women in pandemic planning to avoid preventable deaths.

"Some strains cause no or mild disease in wild birds while others can cause severe disease in poultry, like chickens. Certain strains can infect mammals including seals, livestock, and occasionally humans."

The most common strains of bird flu are H5N1 and H7N9. H5N1 was originally detected in 1997 in Hong Kong and reappeared in 2003, spreading rapidly to birds in Asia, the Middle East, America's, Europe and Africa.

Health Minister Mark Butler also noted human infections with avian influenza were rare in a recent Australian government announcement of $95 million to fight bird flu.

However, the governor's office noted no person to person spread of bird flu had been detected in the state.

Gov. Newsom said the risk to the public remained low, but they will continue to take all the steps needed to prevent the spread of the virus.