Over the years, varying illnesses emerge from the shadows, gripping the headlines with frightening buzzwords like “contagious” and “pandemic.” This year, it’s Zika, a mosquito-borne virus capable of causing birth defects for pregnant women who become infected. The year before, it was Ebola, a fatal diagnosis marked by massive amounts of internal bleeding. The dramatic nature of these conditions – diseases du jour, if you will – often contribute to widespread panic.
A more malicious threat, however, lurks just outside the spotlight. This evasive ailment, in existence for centuries, doesn’t get as much press, but it’s arguably one of the largest hazards to public health.
“The flu is more serious than any of these diseases we’ve been talking about,” said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases in Bethesda, Maryland. “It is not a trivial disease.”
Fauci was awarded the 2007 National Medal of Science for his work with HIV, developing treatments to help patients with the virus live longer, better lives. His research – paramount to the understanding of the world’s most devastating epidemics – focuses on the interaction between the immune system and infectious agents, deciphering the relationship between pathogen and host.
To understand this exchange is to understand any virus, including the flu, which is spread via “respiratory aerosols” – tiny droplets created when people cough or sneeze. The virus, which peaks in activity from December to March, boasts a long history of plaguing mankind.
The name “influenza” comes from Italy, coined after a 15th century epidemic attributed to “influence of the stars,” according to the Centers for Disease Control and Prevention. Centuries later, a 1918 outbreak of the “Spanish influenza” sickened 20 to 40 percent of the worldwide population, killing more than 50 million people. In 1938, Jonas Salk and Thomas Francis developed the first flu vaccines, preventing a future catastrophic outbreak.
How many people will the flu kill this year?
The CDC can’t be sure. The agency estimates that annual flu-related deaths have ranged from about 3,000 to 49,000 people for seasons from 1976 to 2007. But tracking fatalities remains a challenge. States aren’t required to report individual flu cases or deaths in people older than 18 years of age, the agency says.
In addition, influenza isn’t usually listed on death certificates of people who die from flu-related complications such as pneumonia. In many aspects, the flu is elusive – so elusive, in fact, that the virus itself changes every year.
Each season, the flu’s hemagglutinin molecule – the main protein on the surface of the virus – mutates. The changes can be spontaneous or a result of pressure from the immune response within a population, Fauci said. “Sometimes it doesn’t change at all, which is unusual,” he added. “Sometimes it changes enormously, and that’s how you get a pandemic.”
Generally, there are three strains of influenza that circulate: H3N2, H1N1 and Influenza B. This year, we’re dealing with a Hong Kong strain of H3N2, a California strain of H1N1 and the Brisbane strain of Influenza B. The morphing viruses – taking their names from the locations where they were first isolated – force scientists into a “race against the clock” to create a new vaccine in time for peak season, Fauci said.
“Even though vaccines from the flu save hospitalizations every year, it’s an imperfect situation,” he added. “We need to do a much better job in predicting what the strain will be from year to year.”
After scientists isolate what they predict will be the seasonal strain, they have about six months to concoct a vaccine. Then, the vaccine must be mass produced. This flu season, manufacturers project distribution of 157 to 168 million injectable flu vaccines to the United States.
“It costs a lot of money to vaccinate most of the population every single year for the same disease,” Fauci said. “Imagine if you had to do that for measles and polio. That would be crazy.”
Fauci remains optimistic that an annual flu shot might one day be a thing of the past. A “universal vaccine” – one capable of preventing all strains of the virus – is currently being developed by scientists at NIH. Animal models, Fauci said, show they’re on the right track.
“In the next several years, we’re very likely to have one,” he said. “It won’t be the perfect universal vaccine, but we’ll have something much better than the individual vaccines.”
In the meantime, “Don’t play Russian roulette,” Fauci says. “If you’ve never gotten a flu shot, get one now,” he added. “People don’t realize you can get pretty sick from influenza. The chances of you dying are very low, but you could lose several days or more of work.”
Last year, nearly 46 percent of Americans – about 144 million people – got vaccinated, a drop of 1.5 percent from the year prior. By getting sick, you’re hurting yourself – but also the economy. According to a study from the Society for Risk Analysis, a pandemic flu outbreak could yield a GDP loss between $34.4 billion and $45.3 billion. A separate study from the University of North Carolina at Chapel Hill estimates that a seasonal flu outbreak costs $5.8 billion in health care expenses and lost productivity. Most of that money – about 80 percent – is attributed to people who did not get vaccinated.
Unfortunately, Fauci said, today’s flu shots aren’t 100 percent effective, but there are many non-medical ways to protect yourself and others. “Don’t go to crowded places in the middle of an outbreak,” Fauci said. “When you’re sick during the flu season, don’t go to school and don’t go to work. If you feel you have symptoms, cover your cough.” Heed these words. In a world where few things are guaranteed, the flu remains constant.
“This isn’t a rare event. Every year during the winter season, we’re going to get an influenza outbreak,” Fauci said. “You can take that to the bank.”