 If the causal agent is suspected to be bacterial a blood culture and complete blood count is performed.An adrenocorticotropic hormone stimulation test can be performed to assess adrenal function.Routine vaccination against meningococcus is recommended by the Centers for Disease Control and Prevention for all 11- to 18-year-olds and people who have poor splenic function (who, for example, have had their spleen removed or who have sickle-cell disease which damages the spleen), or who have certain immune disorders, such as a complement deficiency.