Brief answer....given below Detailed answer.... Hello, Thanks for the query. Staph is a common type of bacteria living on skin and mucous membranes ( eg. In nose ) of humans.Staph aureus is the most important of these bacteria in human diseases.About 15-40 per cent of healthy humans are carriers of Staph.aureus,which means having bacteria on skin but without any active infection. Despite being harmless in most people,S,aureus is capable off causing various infections of skin and other organs. Most infections take place in normal individuals but certain underlying conditions increase the risk of infection,like... Poorly controlled diabetes Malnutrition Anaemia Alcoholism Intravenous drug users People with HIV/ AIDS People using steroids or immunosuppressants. Now coming to your querries. 1st...Generally not serious but can result in severe illnesses specially if you are having low immunity and conditions as mentioned above. 2nd ..it is contagious and can be passed to others. 3rd....your nose bump definitely looks part of it. Take proper precautions,keep washing your hands repeatedly,take bath twice daily,avoid touching your wounds with your hands,change and wash your towels several times a week,wash your clothes and bed linens regularly. I hope it helps,however you may revert to me for any further query. Best of luck Thanks

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