Seasonal flu shots: how well do they work per CDC and WHO?

Not well at all, even when cherry-picking the studies

Update for 2024 below. I have posted these data before for previous years. Note that during the past TEN flu seasons, CDC only claims that seasonal flu shot efficacy was greater than 40% for 2 seasons. Despite FDA slowly converting the US seasonal flu shots from 3 antigens to 4, it has now reversed that plan and told manufacturers to go back to 3 antigens only (1 each Influenza A H1N1 and 1 H3N2, 1 Influenza B antigen).

I can find NO EVIDENCE that an mRNA vaccine has been approved for SEASONAL flu in the US. Despite this, given FDA’s recent, repeated failures to properly regulate (i.e., slowness or failure to take off the market these products when they are found to have flaws that kill those using them, including vaccines, drugs, baby formulas, etc.,) I advise great care with the use of these products.

Here is an FDA sentence I love, because it is so obviously covering up some uncomfortable fact:

In the interest of public health, FDA strongly recommended to influenza vaccine manufacturers the removal of the B/Yamagata lineage virus from seasonal influenza vaccines in the U.S. for the 2024-2025 influenza season.

Was the problem with the B Yamagata antigen or the presence of a 4th antigen? What was the problem? Why won’t FDA admit what “the interest of public health” means? When will our federal health agencies become transparent?

https://www.webmd.com/vaccines/news/20241004/the-flu-vaccine-might-be-less-effective-this-year

Note that CDC claims the vaccine is better at preventing hospitalization than it is at preventing infection. So if it is claimed to be 35% effective at preventing hospitalization, expect it to be 20-25% effective at preventing infection.

Given the risk of side effects, you are probably more likely to have a side effect than a benefit from the shot this year. I hope this helps those whose hospitals are pushing the shot for employees.