So I’m really quite interested in seasonality of infections. I first became interested in it when looking at increases in E. coli bacteraemia for ARHAI (report here) because of Jennie Wilson’s excellent paper showing seasonality of gram negative bacteraemia, echoed by similar observations and conjecture on warmer weather, more infection. This is true in hospitals as well as the community. Why would this be? We have tussled with increasing E. coli bacteraemia in the UK for a few years now. Goes up every summer, does not return to the baseline, goes up again next summer etc., etc.. Other countries have also reported this. I have heard some suggest this is due to longer hours of daylight leading to more barbeques and more sexual activity. Given that the majority of infections in the UK are >70 years of age, my senior years have no fears for me then.