An Arizona State University researcher is trying a radical approach to speed up the process of making influenza vaccines: using salmonella.
Currently, the 50-year-old process in use requires injecting a weakened flu virus into millions of fertilized hens’ eggs, incubating them, and extracting and purifying the serum.
The whole process can take six months.
But if ASU researcher Roy Curtiss figures out how to make salmonella work, it could mean that people will drink a liquid with a salmonella bacterium that has been neutralized and laced with flu-virus genes.
Salmonella is a common cause of food poisoning, invading the gut and causing diarrhea and other symptoms. That same mechanism is what makes Curtiss confident that salmonella is a perfect delivery system for vaccines. His salmonella is genetically modified so it doesn’t cause poisoning.
Salmonella is able to invade lymph nodes in the intestines, which then can trigger immunity in the rest of the body. That’s a more direct route to spurring the immune system to make antibodies against an invader, such as a flu virus.
People could drink the vaccine. Curtiss said he thinks an oral vaccine would have wider acceptance than those given with needles because there is less pain and less risk of infection. Needles also are more expensive and require some medical expertise.
While there is no guarantee the process will become the vaccine method of choice for most Americans, including as a replacement for annual flu shots, it points to the multipronged research endeavors being funded to prepare for a flu pandemic that health officials long have feared.