Not rare!<p>streptococcus + sepsis + necrotizing soft tissue infection.<p>Anyone who has worked with bacteria on agar will be fully aware of streptococcus (Staphylococcus aureus).<p>Those round yellow blobs that infect areas of the agar.<p>In my own work I noticed that I had a lot of agar contamination simply because I failed to brush my teeth prior to doing agar work.<p>We sometimes forget how contaminated our mouths are with all sorts of bacteria living in there.<p>The there are the masks!