Weather shot in the arm for flu vaccines race

Chinese University researchers have made significant advancements in predicting the evolution of the influenza virus, leading to the development of more effective flu vaccines.

Their computational model, beth-1, functions like a weather forecast by projecting virus changes. This state-of-the-art model enables the selection of the most suitable virus strain for developing vaccines targeting seasonal flu.

Compared to existing vaccines, the beth-1 model has shown greater accuracy in nearly 90 percent of influenza seasons, researchers said.

Associate professor Maggie Wang Haitian, from the Jockey Club School of Public Health and Primary Care, said flu viruses undergo rapid evolution, necessitating regular updates to vaccine strains to maintain efficacy. Unfortunately, it typically takes at least six months for manufacturers to produce a batch of flu vaccines.

The consequence, she said, is that by the time a vaccine is ready, the virus may have already changed, resulting in reduced effectiveness.

"Accurately forecasting the dominant flu virus strain that will circulate in nine to 12 months would greatly contribute to ensuring the vaccine's efficacy," Wang said.

To develop beth-1, extensive virus genetic, epidemic and meteorological data were used to predict virus changes.

"The model is like a weather forecast, but one that predicts virus populations 12, 18, or even 24 months into the future," she said.

Doctoral student Lou Jingzhi, the study's first author, said researchers calculated the average genetic distance between the forecasted results of different models and the actual circulating viruses in various influenza seasons. They found that beth-1 outperformed current vaccines in 88 percent of influenza seasons.

"Using strains predicted by beth-1 is estimated to increase the expected effectiveness of current vaccines against the H1N1 virus by 13 percent and H3N2 by 11 percent," she said.

Past studies have indicated that a 5 percent increase in vaccine effectiveness could prevent one million cases of illness and 25,000 hospitalizations in a single season in the United States alone.

The researchers are collaborating with mainland institutions to conduct animal experiments aimed at making more effective vaccines using the beth-1 model. They are also prepared to cooperate with local health authorities.

The team has also shared their study results with the World Health Organization and is currently working on forecasting Covid-19 mutations.