Each year in the United States, influenza infection results in an estimated 31 million outpatient visits, 226,000 hospitalizations, and 36,000 deaths. This year, the CDC took a historic move by recommending that physicians vaccinate everyone 6 months of age and older. Even though the FDA and CDC closely monitor influenza each year, neither agency predicted the emergence of a new H3N2 variant, which has caused a considerable number of the deaths this season.
One disconcerting aspect of influenza viruses is their ability to mutate rapidly. Through these mutations, the viruses can vary genetically from season to season and even within a season. This unceasing evolution forces scientists to reformulate the vaccine from year to year, and a few months before flu season, scientists at the FDA guess which strains will circulate among the population.
The FDA developed and approved this season's vaccine based on three virus strains expected to be prevalent. Most experts, including Dr. Karen Midthun of the FDA, agree that vaccination remains the best method of combating the flu. But this year's vaccine proved to be only about 56 percent effective at preventing illness.
Now a stream of recent studies has brought hope for a longer-lasting and better influenza vaccine. New research is poised to create a "universal" influenza vaccine that may soon end the FDA's vaccine gamble. Scientists are looking at ways to counter the evolutionary nature of influenza that could work against any type of the virus.
A universal flu vaccine differs from your average flu shot because it provides the body's immune system with the ability to recognize and specifically target "conserved" portions of the virus, or structural components common to all influenza viruses. By attacking these shared components, the vaccine provides immunity to all the influenza viruses, including the devastating mutant strains that appear without warning.
In theory, a universal vaccine would induce the immune system to produce two kinds of white blood cells, or leukocytes, that would be specifically directed against influenza viruses. The vaccine would generate T-leukocytes to directly attack and destroy infected cells, or B-leukocytes that coat the virus to prevent it from infecting healthy cells. This differs from current vaccines that only generate a B-leukocyte response.
Especially promising is the work of scientists at the National Institute of Allergy and Infectious Diseases, headed by Dr. Gary J. Nabel, who are developing a universal vaccine that could confer decade-long protection from any influenza-A viral strain. Nabel believes that a universal vaccine will come to fruition in a few years. Instead of an annual inoculation, Americans would receive two shots when they are young, and boosters later in life.
As evidenced by this season's epidemic, the need for a universal vaccine is dire. Citing the difficulties in predicting which influenza viruses will predominate during any given season, last month the FDA approved the first quadvariant live-attenuated vaccine, which will replace the currently available trivariant vaccine in the 2013-14 flu season.
Although the FDA seems content to keep up this guessing game, we should not be content to allow this deadly game to continue. The only solution is to increase public funding for the ongoing work toward a universal vaccine. The return on this investment would be improved public health and security against epidemic influenza.
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Adam Zakheim, a graduate of the William Penn Charter School and Haverford College, is pursuing a master's degree at the Jefferson Graduate School of Biomedical Sciences in clinical microbiology with a concentration in infectious and emerging diseases. He last wrote for the Daily News op-ed page (Nov. 2, 2012) about the importance of Obamacare for underage Americans.
