Early signs indicate we’re in for rougher-than-usual flu season

By all accounts, influenza is coming on strong this season, including starting roughly a month earlier than it has for the past several years. While predicting the course of a flu season is dicey at best, that early indicator — and some others — has public health officials concerned that the United States may be in for a rougher-than-usual ride this winter. For starters, the predominant strain picked up in lab tests so far this fall in the United States, including Nebraska, is a strain of influenza A known as H3N2. In the past, seasons dominated by that particular strain have proved worse than others, said Dr. Mark Rupp, professor and chief of the University of Nebraska Medical Center’s infectious diseases division. “Just by its nature, that strain of influenza tends to be a little more virulent and cause a more severe disease,” he said. Australia, which runs a season ahead of the United States, just went through a particularly rough flu season. H3N2 predominated there, too. “Folks feel that’s a harbinger for us all to have a bad season,” Rupp said. In addition, preliminary reports indicate that the flu vaccine was only 10 percent effective against H3N2 in Australia, which uses the same vaccine. That said, public health officials, including the federal Centers for Disease Control and Prevention, still strongly recommend that people get this year’s vaccine. The vaccine, they say, is the best protection we’ve got from what can be a serious, even fatal, illness. The agency estimates that the influenza vaccine averted 40,000 deaths in the United States between the 2005-06 and 2013-14 seasons. “Some years, I’m more wildly enthusiastic than others,” Dr. Tom Safranek, Nebraska’s state epidemiologist, said of the flu shot, “but I still recommend it.” UNMC’s Rupp said it’s not yet clear whether the strain in this year’s vaccine is going to be a good match for the strain that’s circulating. Getting a good match is tricky to start with because the circulating strain continues to change all season long. That’s the virus’ way of evading our immune systems. But the vaccine stays the same. In addition, most of the flu virus used to make flu vaccines these days is grown in chicken eggs, as it has been for decades. But recent studies suggest that the virus may undergo changes in order to grow in those eggs. Those changes may be enough to make the vaccine less effective. According to the CDC, H3N2 viruses are more likely to change than other strains. But even in a year when the strains are mismatched, Rupp said, getting the vaccine can shorten the course of the illness and lower the fever, even keep people out of the hospital. In past years, the vaccine has run between 40 percent and 60 percent effective. Flu viruses also tend to wax and wane, and another strain could come to dominate later in the season. The current vaccine covers four strains, bolstering a recipient’s odds of being covered. Widespread vaccination also helps protect those who are more vulnerable to the flu, generally the very young and the very old. “It’s really incumbent on all of us to form a protective bubble around them, or what we call herd immunity,” Rupp said. The vaccine takes about two weeks to provide full protection, so there’s still time to get it before the crush of holiday mingling. The CDC recommends the vaccine for everyone six months and older who doesn’t have a medical reason not to get it. Survey data indicate that 38.6 percent of Americans six months and older reported receiving flu vaccination through early November, compared with 39.8 percent at the same time last year. Several states in the South and East reported widespread flu activity during the week ending Dec. 2, the most recent report available. While flu activity has been picking up in Nebraska, it has been seen in localized pockets, as opposed to across the entire state. Meantime, the early reports about the vaccine’s less-than-stellar performance in Australia has researchers and public health officials stressing the need for a different means of producing the vaccine. A version of the vaccine produced without eggs is available this year for people with egg allergies. They’re also emphasizing the need for what would be the holy grail of flu vaccination — a universal shot that wouldn’t have to be adjusted and injected each season. “What we’re ultimately looking for is a flu vaccine you can get once or twice in a lifetime,” said Safranek, the state’s epidemiologist. While researchers reportedly are working on such a solution, Rupp said they will have to make some fundamental changes to produce a universal vaccine. “That is, I think, some time away yet,” he said. So, get your shot, if you haven’t already. And forget about that nasal mist from seasons past. It hasn’t proved effective in recent years and is not recommended this year. Safranek also recommended antiviral medications, such as Tamiflu, for people with flu symptoms: a fever higher than 101 degrees, a cough or sore throat, muscle aches and exhaustion. Those who are sick are encouraged to stay home. Those who aren’t can protect themselves by washing or sanitizing hands, avoiding sick people, eating healthfully and getting plenty of rest.