The invisible menace! I’ve often thought it would be great if there was some visible sign that your hands had become contaminated during patient care. I guess that does happen to a degree when hands are visibly soiled – and we know that compliance with hand hygiene is almost universal when that happens. But what about when there’s no visible contamination but invisible and risky contamination with pathogens that can cause HCAI? A helpful systematic review and meta-analysis from 2019 suggests that around 5-10% of HCW working in acute care hospitals or care homes are contaminated with key hospital pathogens.