Flu Cases Surge in the U.S. as a New Variant Emerges
Flu cases are on the rise in the United States, fueled by a new variant of the virus. This surge is expected to continue, particularly as holiday travel ramps up.
The variant, referred to as “subclade K,” prompted early outbreaks in places like the UK, Japan, and Canada. Recently, the Centers for Disease Control and Prevention (CDC) noted that more than half of the states are experiencing high or very high levels of flu activity.
As of December 20, the CDC estimates that the U.S. has seen at least 7.5 million flu-related illnesses, along with 81,000 hospitalizations and around 3,100 deaths this season. This figure includes at least eight fatalities in children, based on data collected before the major holiday gatherings.
New York, in particular, is feeling the impact, with health officials reporting the week ending December 20 had the highest number of flu cases—71,000—recorded since 2004.
It’s still early to determine whether this flu season will be as challenging as last year’s. Nevertheless, health experts emphasize that it’s not too late to receive a flu shot, which can still help reduce the severity of the illness, even in those who do get infected. While this season’s vaccine may not perfectly match the subclade K strain, a preliminary study from the UK indicates that it offers at least some degree of protection, potentially lowering hospitalization risks.
Surprisingly, only about 42% of both adults and children have received a flu vaccination this year, according to the CDC.
What is Subclade K Flu?
The flu virus is quite the shapeshifter, constantly evolving and existing in various forms. Subclade K is a mutated version of one of the H3N2 subtypes of Type A flu, which is typically harsh, especially for older adults.
The mutations within subclade K aren’t significant enough to classify it as a completely new strain, but they are different enough to evade some of the vaccine protection that was targeted at this year’s flu strains, explained Andrew Pekosz, a virus expert at Johns Hopkins Bloomberg School of Public Health.
Will Subclade K Make People Sicker?
The CDC indicates it’s too early to predict the severity of this flu season. Historically, flu seasons driven by any version of H3N2 tend to be tough, often leading to increased infections and more severe illness. However, Pekosz cautions that we need more time to figure out if subclade K is simply easier to spread or if it indeed poses a greater threat.
Regardless, the CDC mentions that there are prescription medications available to treat flu, typically advised for individuals at high risk for complications. That said, they should generally be taken within a day or two of the onset of symptoms.
Who Needs a Flu Vaccine?
The CDC, along with major medical organizations, recommends a flu vaccine for almost everyone aged 6 months and older. Even amid the proliferation of misinformation about vaccines, these flu vaccination guidelines remain unchanged.
Flu is particularly dangerous for those aged 65 and older, pregnant women, young children, and individuals with chronic health conditions like asthma, diabetes, heart disease, and weakened immune systems.
The vaccines are designed to guard against three influenza strains. Despite worries over the new H3N2 variant, they seem to match well against H1N1 and Type B flu, which might also be circulating this year, according to Pekosz.
Vaccines are available for all age groups, including a nasal spray option (FluMist) for those aged 2 to 49. Interestingly, this year, some individuals may even be able to administer the FluMist vaccine to themselves at home.
