Pickering J, Smith-Vaughan H, Beissbarth J, Bowman J M, Wiertsema S, Riley T V, Leach A J, Richmond P, Lehmann D, Kirkham L-A
School of Paediatrics and Child Health, The University of Western Australia, Perth, Australia.
J Clin Microbiol. 2014 May;52(5):1352-7. doi: 10.1128/JCM.03448-13. Epub 2014 Feb 5.
Nontypeable Haemophilus influenzae (NTHI) strains are responsible for respiratory-related infections which cause a significant burden of disease in Australian children. We previously identified a disparity in NTHI culture-defined carriage rates between Aboriginal and non-Aboriginal children (42% versus 11%). The aim of this study was to use molecular techniques to accurately determine the true NTHI carriage rates (excluding other culture-identical Haemophilus spp.) and assess whether the NTHI strain diversity correlates with the disparity in NTHI carriage rates. NTHI isolates were cultured from 595 nasopharyngeal aspirates collected longitudinally from asymptomatic Aboriginal (n=81) and non-Aboriginal (n=76) children aged 0 to 2 years living in the Kalgoorlie-Boulder region, Western Australia. NTHI-specific 16S rRNA gene PCR and PCR ribotyping were conducted on these isolates. Confirmation of NTHI by 16S rRNA gene PCR corrected the NTHI carriage rates from 42% to 36% in Aboriginal children and from 11% to 9% in non-Aboriginal children. A total of 75 different NTHI ribotypes were identified, with 51% unique to Aboriginal children and 13% unique to non-Aboriginal children (P<0.0001). The strain richness (proportion of different NTHI ribotypes) was similar for Aboriginal (19%, 65/346) and non-Aboriginal children (19%, 37/192) (P=0.909). Persistent carriage of the same ribotype was rare in the two groups, but colonization with multiple NTHI strains was more common in Aboriginal children than in non-Aboriginal children. True NTHI carriage was less than that estimated by culture. The Aboriginal children were more likely to carry unique and multiple NTHI strains, which may contribute to the chronicity of NTHI colonization and subsequent disease.
不可分型流感嗜血杆菌（NTHI）菌株可引发与呼吸道相关的感染，给澳大利亚儿童带来了沉重的疾病负担。我们之前发现，原住民儿童与非原住民儿童中，由NTHI培养定义的携带率存在差异（分别为42%和11%）。本研究的目的是运用分子技术准确测定真正的NTHI携带率（不包括其他培养鉴定相同的嗜血杆菌属物种），并评估NTHI菌株多样性是否与NTHI携带率的差异相关。从西澳大利亚卡尔古利-博尔德地区纵向收集的595份0至2岁无症状原住民儿童（n = 81）和非原住民儿童（n = 76）的鼻咽抽吸物中培养出NTHI分离株。对这些分离株进行了NTHI特异性16S rRNA基因PCR和PCR核糖体分型。通过16S rRNA基因PCR对NTHI的确认将原住民儿童的NTHI携带率从42%校正至36%，非原住民儿童从11%校正至9%。共鉴定出75种不同的NTHI核糖体分型，其中51%为原住民儿童所特有，13%为非原住民儿童所特有（P < 0.0001）。原住民儿童（19%，65/346）和非原住民儿童（19%，37/192）的菌株丰富度（不同NTHI核糖体分型的比例）相似（P = 0.909）。两组中同一核糖体分型的持续携带情况罕见，但原住民儿童中多种NTHI菌株定植比非原住民儿童更为常见。真正的NTHI携带率低于培养估计值。原住民儿童更有可能携带独特和多种NTHI菌株，这可能导致NTHI定植的慢性化及后续疾病。
