Annual report of the National Influenza Surveillance Scheme, 2006.
Influenza surveillance in Australia is based on laboratory isolation of influenza viruses, sentinel general practitioner reports of influenza-like illness, and absenteeism data from a major national employer. In 2006, 3,130 cases of laboratory-confirmed influenza were reported to the National Notifiable Diseases Surveillance System, which was one-third lower than in 2005. The influenza season started in mid-June, with peak activity in late August. Influenza A was the predominant type notified (71%), however influenza B activity continued to increase as a proportion of reported cases. Reports of influenza-like illness from sentinel general practitioners showed a slow but steady increase throughout the first half of the year to peak in late August. In 2006, 657 influenza isolates from Australia were antigenically analysed: 402 were A(H3N2), 24 were A(H1N1) and 231 were influenza B viruses. Continued antigenic drift was seen with the A(H3N2) viruses from the previous reference strains (A/California/7/2004 and A/New York/55/2004) and drift was also noted in some of the A(H1N1) strains from the reference/ vaccine strain A/New Caledonia/20/99, although very few A(H1N1) viruses were isolated in Australia in 2006. The B viruses isolated were predominately of the B/Victoria-lineage and similar to the reference/vaccine strain B/Malaysia/2506/2004.
O'Brien
Kathleen
K
Office of Health Protection, Australian Government Department of Health and Ageing, Canberra, Australian Capital Territory. epi@health.gov.au
Barr
Ian G
IG
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001315:Australia / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D018563:Disease Notification; D005260:Female; D006801:Humans; D007223:Infant; D053118:Influenza A Virus, H1N1 Subtype / Q000145:classification*; D053122:Influenza A Virus, H3N2 Subtype / Q000145:classification*; D009981:Influenza B virus / Q000145:classification*; D007251:Influenza, Human / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D012621:Seasons; D018571:Sentinel Surveillance