The vaccines aim to provide broader protection against subtypes of influenza A, which can cause major outbreaks and severe illness in humans and animals.

Both are being developed as live-attenuated nasal sprays, meaning they deliver a weakened form of the flu-causing virus to the body through the nose.

‘Hong Kong flu cases to rise as temperatures drop over Lunar New Year holiday’

“A nasal spray can stimulate the immune system of the respiratory tract, and the probability in preventing infections is likely to be higher,” the insider said.

Flu vaccines currently in use mostly helped to reduce serious complications rather than prevent infection, he added.

The two vaccines being developed worked differently in stimulating the immune system, and researchers wanted to see which worked better, he said.

Currently, there is one nasal spray vaccine registered for use in Hong Kong, and similar to some other flu vaccines, targets four specific strains.

Flu strains keep changing and that means vaccines are updated every year to keep up and people have to get a dose annually to stay protected.

For more than 10 years, scientists worldwide have been trying to develop a universal flu vaccine to protect against multiple strains.

The insider said researchers behind the new vaccines hoped they would provide protection for at least a few years.

They targeted influenza A as previous crises, such as the Spanish flu pandemic in the early 20th century and swine flu pandemic in 2009, were caused by this virus type.

‘Better to work together’: world must learn from Covid-19, expert says

The research in Hong Kong will be supported by the Global Health Institute (GHI), an initiative funded by the Jockey Club, which has pledged HK$3 billion (US$383 million) to help strengthen the city’s capacity to combat infectious diseases.

The institute is expected to start operating in March, insiders said, and Cambridge University and the International Vaccine Institute (IVI) will send people to work in Hong Kong.

Another source said relevant research could be done faster and more accurately by drawing on the experience of the IVI, a non-profit international organisation focused on developing and delivering vaccines.

It had carried out a lot of international clinical trials and set standards in vaccine development, including how to document and fulfil regulatory requirements, the insider said.

With the arrival of collaborators from the IVI and Cambridge, there would be a comprehensive team to carry out vaccine development in Hong Kong “more quickly and accurately”, he said.

He explained that Hong Kong currently had a research gap in bringing experimental vaccines to the next level, whereas the IVI was experienced in testing and running trials in different places around the world.

If things went well, the HKU research could eventually lead to mass production by vaccine companies. “Hong Kong currently doesn’t have such facilities and expertise,” the source said.

Top scientists, including Hong Kong scholar, vow to prepare for next pandemic

The other insider said a small-scale vaccine production facility would be set up on the campus of HKU’s medical school for the first phase of clinical trials, which usually involved a small group of people.

It would comply with the international good manufacturing practice standard to ensure the quality of pharmaceutical products.

The sources said the new set-up and team could put Hong Kong in a better position to prepare for the next pandemic. If another major outbreak occurred, vaccines could be produced more quickly, they said.

The GHI would also help provide training in vaccine trials and project management to overseas scientists and researchers, who could then collaborate with it for research on a wider scale, one of the sources said.