SPN and infection: Previously, using the Experimental Human Pneumococcal Challenge model of infection in which healthy adults were challenged with type 6B pneumococcus, detection of pneumococcus in the nose of adults using SAM once Spn colonization was established was low.9 At day 2 and 6 after 6B exposure, only 1 of 9 (11.1%) and 1 of 7 (14%) Spn-positive adults (carriers by classical culture of nasal washes) was found to be Spn positive by SAM qPCR.