Haemophilus isolates derived from the nasopharynxes of Aboriginal and non-Aboriginal children assessed in this studya

SampleNo. (%) of Haemophilus isolates in:P value (proportion difference)
Aboriginal childrenNon-Aboriginal children
Children carrying culture-defined NTHI on any visit81/100 (81.0)76/180 (42.2)<0.0001
Swabs with presumptive NTHI isolates/total swabs (initial carriage rate)212/504 (42.0)117/1045 (11.1)<0.0001
NTHI-like isolates derived from swabs378217
True NTHI/viable isolates analyzed by PCR346/378 (91.5)192/217 (88.5)0.248
Other haemophili (proportion of misidentification)32/378 (8.5)25/217 (11.5)0.248
Swabs with PCR-confirmed NTHI isolates/total swabs (true carriage rate)183/504 (36.3)98/1045 (9.4)<0.0001
True NTHI isolates available for PCR ribotyping346192
Richness, i.e., no. of ribotypes/no. of true NTHI isolates available for PCR ribotyping65/346 (18.7)37/192 (19.3)0.909
No. of different NTHI ribotypes/total no. of all ribotypes65/7537/75<0.0001
Proportion of unique ribotypes38/75 (50.7)10/75 (13.3)<0.0001
Proportion of unique ribotypes/total individual ribotypes38/65 (58.4)10/37(27.0)0.004
No. of swabs with >1 NTHI PCR ribotype37/183 (20.2)8/98 (8.1)0.010
  • a Where possible, two isolates were collected and stored from each NPA swab.