Would a Seasonal Flu Vaccine Protect You Against H5N1 Bird Flu at All?
It's worth a shot.
As an H5N1 pandemic looms over us, the CDC is strongly recommending flu shots while urging farmworkers to get vaccinated. This year’s shot is trivalent, meaning it contains vital proteins from Flu A strains H1N1, H3N2, and one Flu B virus. In the past, they’ve used a quadrivalent vaccine, but this year they excluded a Flu B strain they believe to have been essentially eradicated (because of enhanced protection measures like masking and clean air). All of this made me wonder how well a seasonal flu vaccine protects against a novel strain. The CDC’s official answer is that it doesn’t. However, there’s a big but they won’t say…
Studies suggest otherwise.
Normally, your immune system only develops a memory of specific antigens. Your immunity to one virus doesn’t transfer to others. However, in the case of flu viruses, cross-protection can happen. In fact, recent research covered in Nature stresses the need for universal flu vaccines that generate mucosal immunity, which could provide protection against a range of strains, even H5N1.
We have the technology to do this. We could already have universal flu vaccines by now if our governments had invested in them.
They didn’t, not really.
Most of us have probably never thought to learn about the different types of flu vaccine on the market. Turns out, there’s a difference. For example, one popular brand this year is Flublok, which claims to offer three times the standard antigen dose and provides 30 percent better protection in clinical studies. During a given season, you can choose between nine different flu shots. Some of them offer an adjuvant, like Novavax does for Covid. It’s usually available only for adults 65 and older. Higher dose adjuvanted vaccines could benefit many of us this year, and it would be nice if public health officials were more forthcoming about that.
Several studies indicate that a seasonal flu vaccine can offer partial protection against H5N1 specifically, even against death.
Let’s get into them.