Say Goodbye to Yearly Flu Shots—The Universal Flu Vaccine

By: Diana Gritsenko, Pharm D. Candidate c/o 2015

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Every flu season, it is the same story: long lines at doctors’ offices and pharmacy counters as patients scramble to get the year’s vaccine before supplies run out. Year after year, doctors and pharmacists groan while explaining over and over again to patients why they need to get a brand new vaccination this year.

The reason behind the frequent vaccinations lies in the nature of the vaccines. Current seasonal vaccines are made from the three most common influenza viruses circulating in a particular flu season. These viruses are grown in eggs (hence the intolerance in some patients with egg allergies) and are weakened or killed so the patient’s immune system can develop antibodies with little to no risk of the patient falling ill from the vaccine itself. However, it takes patients two weeks to develop antibodies from the vaccine, and they might still get the flu from a strain of the virus that they were not vaccinated against.¹

Scientists from the National Institutes of Health (NIH) are developing a universal flu vaccine. Whereas the seasonal flu vaccines prompt the body to make antibodies against the lollipop-shaped head of the virus (called hemagglutinin, or HA), the universal vaccine targets the stem of the HA. What makes this vaccine universal is that the stem of the HA, unlike the head, varies very little from virus to virus. In theory, patients vaccinated with the universal vaccine would be immune to any strain of the flu vaccine—not just the most prevalent.²

Another benefit to this vaccine is that the patient would not need yearly vaccinations. Scientists at the NIH have discovered that immature antibodies can recognize the stem portion of the HA only when those antibodies are attached to the surface of a naïve B cell. Once the attached antibodies recognize the stem of the HA, they replicate into many daughter cells, called memory B cells. Because memory B cells last in the body for several years, or even a lifetime, a patient would remain immune for years after vaccination.²

The significance of the new vaccine is clear to many. However, the implications go beyond the frequency of administration. Periodically, a microorganism evolves and causes a pandemic. For example, in 1918, the Spanish flu infected 20 – 40% of the world’s population and killed 50 million people.³ If such a disease were to arise today, scientists would not be able to develop a vaccine until it was well underway. With the universal flu vaccine, there would already be a weapon against it.

Prime-boosting vaccines, given before administering the seasonal vaccine, are already being tested in humans for safety and efficacy. Soon, these trials will move on to a larger-scale and, within three to five years, we should expect to see efficacy trials for the broadly protective universal flu vaccine.⁴ Hopefully, within this decade, health professionals and patients alike will be relieved of seasonal flu vaccines.

SOURCES:

1. Seasonal Flu Shot. Centers for Disease Control and Prevention. http://www.cdc.gov/flu/about/qa/flushot.htm. Accessed April 23, 2013.
2. NIH scientists map first steps in flu antibody development. National Institutes of Health News. http://www.nih.gov/news/health/aug2012/niaid-29.htm Accessed April 23, 2013.
3. Pandemic flu history. Flu. http://www.flu.gov/pandemic/history/index.html. Accessed April 23, 2013.
4. NIH scientists advance Universal Flu Vaccine. National Institute of Allergy and Infectious Diseases. http://www.niaid.nih.gov/news/newsreleases/2010/Pages/universalfluvax.aspx Accessed April 23, 2013.