Following publication of this paper, the authors realised that there were some errors in the reporting of the results on IL-6. This article has now been updated to include the correct values, following re-running of all analyses. For details of the changes made, please see the associated correction. This article was also originally published under standard licence, but has now been made available under a [CC BY 4.0] licence. The PDF and HTML versions of the paper have been modified accordingly.