Interesting study, but as the authors concede, one can't quite rule out that the causal flow is in the opposite direction to that which they propose - that is, people with lower cognitive ability are more likely to end up with infections, and people with much lower cognitive ability are more likely to end up with severe infections.
I mean, consider people with dementia, sat in their own faeces (at the severely diminished/severe infection end of the scale), or people with lower intellect lower on the socio-economic scale engaging with jobs where they're more likely to end up with infections - construction, handling hazardous waste, etc. etc.
I mean, consider people with dementia, sat in their own faeces (at the severely diminished/severe infection end of the scale), or people with lower intellect lower on the socio-economic scale engaging with jobs where they're more likely to end up with infections - construction, handling hazardous waste, etc. etc.