The US government is launching a programme to modernize the development of flu vaccines. President Donald Trump signed an executive order on 19 September directing the Department of Health and Human Services to come up with a plan and budget for the effort within 120 days.

The goal is to improve the country’s ability to prepare for a potential future outbreak of pandemic flu, and to develop better vaccines to protect against seasonal outbreaks.

The programme will support research to develop a universal flu vaccine , to replace the seasonal vaccine developed each year. The government also plans to create a strategy for switching to faster methods of producing seasonal flu vaccines, a senior administration official told reporters on 19 September. Manufacturers produce most flu vaccines using chicken eggs, a process that takes at least six months.

Influenza viruses mutate constantly, so the strains that circulate differ from year to year. This means that vaccines must be tailor-made for each flu season. But over the past several years, flu shots have only been about 44% effective. That’s partly because the slow process of producing vaccines in eggs creates a months-long lag between when researchers predict which strains will circulate during flu season and when vaccines reach the public. In years with especially bad mismatches between a vaccine and the virus, the effectiveness of a flu shot can drop to less than 20%.

Better and faster

Two other faster production methods exist, and the vaccines they produce are approved by the US Food and Drug Administration (FDA). But those vaccines are slightly more expensive than ones made from chicken eggs.

One of the faster techniques, which uses cell cultures to make flu vaccines, is also more effective than egg-based ones, according to the FDA. The agency estimated that one cell-based vaccine protected about 20% more people than vaccines produced using conventional methods during the 2017-2018 season. Cell-based vaccines account for 10-15% of the flu vaccine market.

The second method uses recombinant technology, where manufacturers insert influenza virus genes into insect cells. The cells then churn out a vaccine, which workers harvest and purify. This technique can produce vaccines within six to eight weeks and accounts for about 1-2% of the market.

A highly effective seasonal flu vaccine, produced rapidly at the start of an influenza pandemic, would save the United States an estimated US$953 billion by preventing deaths and hospitalizations, according to the White House Council of Economic Advisers .

The timing of vaccine production would be less of a concern if researchers could develop a universal influenza vaccine that protects against many strains of the virus, said another senior administration official. This would also eliminate the need to predict which strains will circulate every year.