Invasive pneumococcal disease in Australia, 2009 and 2010

Enhanced surveillance for invasive pneumococcal disease (IPD) was conducted in all Australian states and territories in 2009 and 2010 with comprehensive comparative data available since 2002. There were 1,556 cases of IPD notified to the National Notifiable Diseases Surveillance System in Australia in 2009, a notification rate of 7.2 cases per 100,000 population. In 2010 there were 1,640 cases, a notification rate of 7.4 cases per 100,000. The overall rate of IPD in Indigenous Australians was almost 6 times the rate in non-Indigenous Australians in both 2009 and 2010. In 2009 and 2010, notification rates of IPD caused by serotypes included in the 7-valent pneumococcal conjugate vaccine (7vPCV) continued to decrease across all age groups. Rates of IPD caused by non-7vPCV serotypes continued to show an increasing trend in both Indigenous and non-Indigenous children aged less than 5 years. In Indigenous adults (≥50 years), rates of IPD caused by both 23-valent pneumococcal polysaccharide vaccine (23vPPV) serotypes and non-23vPPV serotypes continued to show an overall increase, particularly in 2010. There were 110 deaths attributed to IPD in 2009 and 137 in 2010, although it should be noted that deaths may be under-reported. The number of invasive pneumococcal isolates with reduced penicillin susceptibility remained low and reduced susceptibility to third generation cephalosporins was rare.