2025 Flu Type A. The seasonal flu vaccine protects against the influenza viruses that research suggests will be most common during the upcoming season. The centers for disease control and prevention today released an advisory recommending clinicians expedite subtyping of type a influenza samples from hospitalized.
These include an influenza a (h1n1) virus, an influenza a (h3n2). If you’re feeling sick, it helps to know the difference between flu a and flu b symptoms, experts say.