Previous Article | Next Article ![]()
Journal of Clinical Microbiology, May 1999, p. 1524-1531, Vol. 37, No. 5
Division of Biochemistry and Molecular
Biology,
Received 13 October 1998/Returned for modification 8 December
1998/Accepted 28 January 1999
We used pulsed-field gel electrophoresis to study the epidemiology
and population structure of Haemophilus influenzae type b.
DNAs from 187 isolates recovered between 1985 and 1993 from Aboriginal
children (n = 76), non-Aboriginal children
(n = 106), and non-Aboriginal adults
(n = 5) in urban and rural regions across Australia
were digested with the SmaI restriction endonuclease. Patterns of 13 to 17 well-resolved fragments (size range, ~8 to 500 kb) defining 67 restriction fragment length polymorphism (RFLP) types
were found. Two types predominated. One type (n = 37)
accounted for 35 (46%) of the isolates from Aboriginals and 2 (2%) of
the isolates from non-Aboriginals, and the other type
(n = 41) accounted for 2 (3%) of the isolates
from Aboriginals and 39 (35%) of the isolates from non-Aboriginals.
Clustering revealed seven groups at a genetic distance of ~50%
similarity in a tree-like dendrogram. They included two highly
divergent groups representing 50 (66%) isolates from Aboriginals and 6 (5%) isolates from non-Aboriginals and another genetically distinct
group representing 7 (9%) isolates from Aboriginals and 81 (73%)
isolates from non-Aboriginals. The results showed a heterogeneous
clonal population structure, with the isolates of two types accounting
for 42% of the sample. There was no association between RFLP type and
the diagnosis of meningitis or epiglottitis, age, sex, date of
collection, or geographic location, but there was a strong association
between the origin of isolates from Aboriginal children and RFLP type
F2a and the origin of isolates from non-Aboriginal children and RFLP
type A8b. The methodology discriminated well among the isolates
(D = 0.91) and will be useful for the monitoring of
postvaccine isolates of H. influenzae type b.
0095-1137/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.
Pulsed-Field Gel Electrophoresis Used To
Investigate Genetic Diversity of Haemophilus influenzae Type
b Isolates in Australia Shows Differences between Aboriginal
and Non-Aboriginal Isolates
*
Corresponding author. Mailing address: Gadi Research
Centre, Faculty of Applied Science, University of Canberra, Canberra, ACT 2601, Australia. Phone: 61-6-6201-5451. Fax: 61-6-6201-5727. E-mail: patmoor{at}ozemail.com.au.
Journal of Clinical Microbiology, May 1999, p. 1524-1531, Vol. 37, No. 5
0095-1137/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»