Correlation does not equal causation
Here’s a story the anti-vaccine crowd is sure to jump on:
“Finland Suspends H1N1 Vaccine
The Finnish National Institute for Health (THL) proposed suspending vaccinations for H1N1 swine flu, due to suspected links to increased narcolepsy in children and adolescents, the body announced this week.
Six cases of narcolepsy, a chronic disorder causing excessive daytime sleepiness and extreme fatigue, have been reported after patients had been receiving the Pandemrix vaccine.
Six cases of narcolepsy is consistent with annual averages, reports THL, but all of these patients were affected after being vaccinated, and there are nine additional cases that have not yet been confirmed.
Now since this is a mainstream media article versus a scientific publication, there are some questions that definitely need to be answered.
Was the diagnosis of Narcolepsy made by combination of history plus multiple sleep latency test?
Were any of said patients displaying any symptoms preceeding vaccination?
Did these individuals have either lumbar punctures or blood tests performed to detect the HLA-DQB1*0602.marker?
[This while not a diagnostic tool per say would however provide interesting immunological evidence]
What makes this all interesting, is that increasing research seems to be pointing towards Narcolepsy having an auto-immune origin in the body. In the simplest terms, individuals with narcolepsy commonly lack hypocretin/orexin [hcrt/ox] producing neurons. The lack of hcrt leads to a disruption in the normal neuro-chemical functioning of the brain which leads to the symptoms of the disorder. [A discussion of which is beyond the scope of this blog--however I can provide references]