Hong Kong's Dr Sophie Valkenburg part of team working on lifelong flu shot

Cooler weather heralds the peak influenza season in Hong Kong, and it's time to book ourselves in for a flu jab. It's no one's favourite annual event, but in the future we might be able to acquire lifelong immunity with just a single shot.

Dr Sophie Valkenburg is a post-doctoral research fellow at Hong Kong University's School of Public Health. She's part of a team working in collaboration with researchers at the National Institutes of Health in the United States to develop a new type of influenza vaccination which promises to be more effective, and longer lasting, than anything now available.

"The current generation of flu vaccines are good but they have limitations," says Valkenburg. These limitations include the notorious seasonality. "The current vaccine requires worldwide surveillance from a network of labs, coordinated by the World Health Organisation. They predict which strain to include in the vaccine for the upcoming flu season".

The key to designing a truly effective vaccine is to tailor it to trigger a response that's even stronger than our natural response to the actual flu virus, but without making you ill.

When we catch the flu, our immune system detects the infection and mounts a multi-pronged defence. An army of antibodies, tailor-made to attack the particular virus, are produced. The antibodies mostly bind to a virus's surface, preventing it from entering healthy cells.

The body also produces T cells. There are two main types. Killer T cells hunt down infected cells and destroy them. Helper T cells play a less aggressive but equally important role, orchestrating the work of the other immune cells, boosting the production of antibodies and coordinating the activity of the killer T cells.