Researchers from the Johns Hopkins Bloomberg School of Public Health developed a flu vaccine in nasal spray form which is more effective among those under the age of two and over the age of 49. Both of these groups currently are not approved for nasal administration of the flu vaccine.
Nasal spray vaccines current protect against such flu strains such as influenza A strains (H1N1 and H3N2) and two influenza B viruses. According to the Centers for Disease Control and Prevention some evidence shows that nasal spray flu vaccines are more effective in younger children in comparison to getting an injection.
Researchers uncovered that the weakened flu virus found in the nasal spray vaccine can be further weakened to support the health of younger children or made stronger for those over the age of 49.
Lead study author, Andrew Pekosz, said, “We think we can use our molecular, rational design approaches to make a better flu vaccine for people who really need it. We can do it in a sophisticated and accurate way, not in a blind manner, which is how these vaccines are usually developed.”
There are high-dose vaccines currently available for seniors as typically flu vaccines tend to be less effective in older individuals. As we age our bodies create more antibodies in the nasal tract as we experience many different strains of the flu over the years. This is why weakened flu viruses are not used in seniors.
Pekosz highlighted that current vaccines are not as effective in seniors and he is hopeful that the new nasal spray vaccine will offer better protection. Seniors are at highest risk of getting the flu and furthermore experiencing its sometimes severe complications.
Although children over six months of age can receive the injectable version of the flu vaccine, it is still recommended that the nasal version is more effective. Allowing children under the age of two to receive a nasal vaccine will add further protection against flu strains.
With the use of cells from the nasal tract, researchers studied the weakened strain of the flu virus found in the nasal spray and compared its behavior with the actual flu virus. Researchers found that the weakened flu virus behaves differently than once researched. Previous research showed that the virus-infected cells send out harmless, non-infectious particles which are picked up by the immune cells and become attacked to create antibodies. The new research suggests this response is not as forceful as once believed.
The new product will be called FluMist and contains nine mutations of the flu virus. Adjustments to the mutations can help determine a stronger vaccine and a weaker one both useful for small children and older adults.
Researchers are hopeful of their new product and believe if all goes well we can begin to see the new flu vaccine option as early as six months to a year.
The study was published in Vaccine.