I went for a conceptual pun on computer antivirus software, because I think hand washing works in a similar way. Hand washing provides a firewall against viruses and germs to ensure that we don't allow them access to the body. It is the first line of defence and good practice in general life. This concept features a basic block print style aesthetic (of course I am a fan of Saul Bass), paired with a relatively recent typeface and simple palette. My approach is that the message should be the tip of the spear, and the design formed around it like a strong handle.