Figure 1
Experimental pneumococcal colonization in young (18–55 years, n = 57) and older adults (> 55 years, n = 55). (A) Frequency of Spn6B pneumococcus in nose (NW) and oropharynx (OPS) in both age groups. Detection of pneumococcal DNA was determined by multiplex qPCR. Participants with qPCR results positive for Spn6B (CT < 40) in the nose and oropharynx per day post-exposure per age group were: Young NW: D2 n = 36/57, D7 n = 34/57, D14 n = 23/29, Young OPS: D2 n = 28/57, D7 n = 29/57, D14 n = 22/28, Older NW: D2 n = 22/55, D7 n = 19/55, D14 n = 11/19, Older OPS: D2 n = 10/55, D7 n = 14/55, D14 n = 11/19. The number of volunteers with Spn6B + sample (CT < 40) in each day post-exposure is expressed as a percentage (%) of the total number of volunteers. Statistical significance was assessed by Fisher’s contingency test: Young vs Older adults: NW D2 P = 0.014, D7 P = 0.008, D14 P = 0.1931 and OPS D2 P = 0.0007, D7 P = 0.007, D14 P = 0.1946, Older adults NW vs OPS: D2 *P = 0.020. (B) Density of Spn6B pneumococcus in nose (NW) and oropharynx (OPS) in both age groups. Each time point represents the average density of SPN6B + per study day per niche. Data was log transformed. Graphs were created in GraphPad Prism version 5.0 for Windows, GraphPad Software, USA, www.graphpad.com.
