Issue link: https://tmcpulse.uberflip.com/i/735225
t m c » p u l s e | o c t o b e r 2 0 1 6 6 Their Best Shot How global surveillance, data dumps and chicken eggs lead to a yearly flu vaccine O ctober marks the beginning of flu season, a harbinger of coughing, aches, fevers, chills and hand sanitizer. Unfortunately, it also means fatalities— as many as 49,000 flu-related deaths each year in the United States. Individuals with weakened immune systems, and especially the very young and the elderly, are most at risk. But top public health organizations, including the Centers for Disease Control and Prevention (CDC) and the American Academy of Pediatrics, recommend all individuals six months and older receive the flu vaccine to protect against the pervasive virus. Vaccinations boost the body's defense system by introducing the same infection they are designed to fight. After receiving a vaccination, the body's immune system will produce T-lymphocytes and antibodies, armed and ready to attack the infection it believes to be present. Because nature is so intelligent, the human body will store in its memory these specific antibodies so that if and when it is exposed to the real virus, it will already be equipped with the necessary tools. Which raises the question: Why should people get the flu shot each year? Shouldn't our bodies be immune after one vaccination, or after coming down with the flu itself? Here's the other thing about nature: it evolves. And viruses are no different. Like humans, they are constantly fight- ing to survive, and while we combat them with vaccines, they evade us through mutation. That's why each year, scientists work to create an updated vaccine made up of the top three or four strains of the flu virus, including two influenza A viruses (like H1N1 and H3N2) and at least one influenza B virus. The challenge for experts is predicting which of the thousands of variants will be the most prevalent each year. The decision has to be made months in advance—February for the northern hemisphere and September for the southern—so there is ample time to design and produce the vaccine by peak flu season. "You're always trying to choose the correct strain that is likely to take off. You're doing this with data that has been collected," explained flu expert Pedro Piedra, M.D., a professor in the Department of Pediatrics as well as Molecular Virology and Microbiology at Baylor College of Medicine. "What we're really looking for is: Are there new viruses? There will always be new viruses, but are there new viruses that are different that we need to worry about?" B y A l e x a n d r a B e c k e r Most flu vaccines are manufactured by using eggs. The seed virus is injected into a fertilized chicken egg, where it can multiply. Credit: Associated Press Flu Vaccine Source: The Centers for Disease Control and Prevention get sick with the flu for the first four months of their lives than babies of unvac- cinated women. A study has shown that babies of women who got a flu vaccination during pregnancy were about ⅓ less likely to 1.9 million illnesses were prevented during the 2014-2015 flu season thanks to vaccinations. 67,000 flu-related hospitalizations were prevented during the 2014-2015 season because of the flu vaccine. The CDC estimates that 150 million doses of the flu vaccine. Each year, private manufacturers supply the U.S. market with more than An estimated