Have you recently developed chills, muscle aches, headaches, and venomous spurs on your heels? I hate to break it to you, but you might just have the Aussie flu, a strain of the virus that wreaked havoc in the Land Down Under during the 2017 flu season. Known as H3N2, the bug has now spread to the UK, causing many Americans to wonder if it will hit the United States next. Brace yourself: If the Australian flu season is any indication, an already rough winter might get rougher.
After the Southern Hemisphere's 2017 flu season, which lasts roughly from April until September, wrapped up, Australian public health officials released their data. Spoiler alert: It didn't look good. The country reported record-high numbers of flu infections, with above-average hospitalizations and deaths, and the Australian flu vaccine was estimated to have only an effectiveness of 10 percent. Overall, according to the BBC, Australia's most recent flu season was the worst it has experienced in more than a decade.
So what does all that have to do with H3N2? According to the Centers for Disease Control (CDC), the flu virus is actually made up of four different types, which are further broken down into different strains. The flu vaccine doesn't inoculate against all these strains, but it does protect against the most common types each season. H3N2, which has been dubbed the Aussie flu after all the trouble it caused in 2017, is a strain known for being particularly nasty.
"Although flu symptoms are typically similar no matter the strain of influenza, history has shown that seasons in which H3N2 influenza A is the dominant strain have been more severe," explains VeryWell.com. While most flu symptoms subside within a week, the virus can be deadly for vulnerable groups like the very old and very young, and in the past, H3N2 has been especially severe in the elderly.
As you've probably guessed by now, H3N2 was the most common strain during Australia's 2017 flu season.
According to the CDC, it's included in the flu vaccine used in the United States each year. However, despite being a match for the H3N2 strain, the vaccine in Australia was less effective than usual. In December, a report in the New England Journal of Medicine suggested that because the U.S. will use the same vaccine as Australia this year, it's possible that it will be similarly ineffective against the strain. The authors wrote:
"The preliminary estimate of vaccine effectiveness against influenza A (H3N2) was only 10%. The implications for the Northern Hemisphere are not clear, but it is of note that the vaccine for this upcoming season has the same composition as that used in the Southern Hemisphere. As we prepare for a potentially severe influenza season, we must consider whether our current vaccines can be improved and whether longer-term, transformative vaccine approaches are needed to minimize influenza-related morbidity and mortality."
Currently, H3N2 is in the news again because it appears to have hit the UK. On Monday, The Telegraph reported that flu-related hospital admissions in the UK nearly tripled within a week, and one in four of these patients had caught H3N2. Health experts have cautioned against panicking, though, pointing out to the BBC that an increase in flu infections is to be expected this time of year.
That being said, this doesn't definitively mean the U.S. will have similar problems with H3N2. The flu season in other countries is merely an indicator, not a surefire predictor. Furthermore, medical experts still recommend getting the flu shot, which protects against multiple strains. The CDC states that the vaccine is the best way to prevent coming down with the virus, even if it has already hit your community. Aside from getting the vaccine, you can also reduce your chances of catching the flu by washing your hands frequently and staying away from people who are ill. Otherwise, you might find yourself laid up for a week with nothing but the television to keep you company.