I’ve been meaning to blog on this editorial about ethnicity as a risk factor (or not!) for infection by Prof Leibovici in Clinical Microbiology and Infection for a while. The basic story is that “ethnicity” often falls out as associated with infection-related variables (e.g. colonisation or infection with resistant bacteria), but the editorial poses an important question: it is actually ethnicity, or something co-correlated with ethnicity (e.g. socio-economic status) that is the causal risk factor?