“The article”? There are literally hundreds of them. This is a very well known phenomenon.

Unsurprisingly, the virus infection is much more likely to cause narcolepsy than was the vaccine, so vaccination against H1N1 protects against narcolepsy overall. But since this only happened with a single vaccine, it was replaced by the other vaccines.

For anti-vax loons reading this, I’ll point out that the hysterical anti-vax voices didn’t find this out, it was discovered very rapidly by the usual surveillance that public health groups routinely conduct. Vaccine-associated effects are routinely detected even when they only occur at a 1 in 20,000 incidence (or much lower, as we saw with the J&J COVID vaccine, where adverse effects were rapidly identified at the 1 in 200,000 level). And even though the vaccine overall was protective and beneficial, when these very rare events were detected the vaccine was immediately pulled from use.