The impact of the pandemic influenza A(H1N1) 2009 virus on seasonal influenza A viruses in the southern hemisphere, 2009.
Data collected over winter 2009 by five World Health Organisation National Influenza Centres in the southern hemisphere were used to examine the circulation of pandemic and seasonal influenza A strains during the first pandemic wave in the southern hemisphere.There is compelling evidence that the pandemic influenza A(H1N1) 2009 virus significantly displaced seasonal influenza A(H1N1) and, to a lesser extent, A(H3N2) viruses circulating in the southern hemisphere. Complete replacement of seasonal influenza A strains, however, was not observed during the first pandemic wave.
Blyth
C C
CC
Centre for Infectious Diseases and Microbiology Laboratory Services, Institute of Clinical Pathology and Medical Research, Westmead Hospital, Westmead, New South Wales, Australia. ccblyth@meddent.uwa.edu.au
Kelso
A
A
McPhie
K A
KA
Ratnamohan
V M
VM
Catton
M
M
Druce
J D
JD
Smith
D W
DW
Williams
S H
SH
Huang
Q S
QS
Lopez
L
L
Schoub
B D
BD
Venter
M
M
Dwyer
D E
DE
D005843:Geography; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000302:isolation & purification; D053122:Influenza A Virus, H3N2 Subtype / Q000302:isolation & purification; D007251:Influenza, Human / Q000453:epidemiology*; D058873:Pandemics; D012621:Seasons; D014944:World Health Organization