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Background: Most studies use indirect cohort or case-control methods to estimate vaccine effectiveness (VE) of 7- and 13-valent pneumococcal conjugate vaccines (PCV7 and PCV13) against invasive pneumococcal disease (IPD). Neither method can measure the benefit vaccination programs afford the unvaccinated and many studies were unable to estimate dose-specific VE. We linked Australia's national immunisation register with health data from two states to calculate IPD incidence by vaccination status and VE for a 3 + 0 PCV schedule (doses at 2, 4, 6 months, no booster) among a cohort of 1.4 million births., Methods: Births records for 2001-2012 were probabilistically linked to IPD notifications, hospitalisations, deaths, and vaccination history (available until December 2013). IPD rates in vaccinated and unvaccinated children <2 years old were compared using Cox proportional hazards models (adjusting for potential confounders), with VE = (1 - adjusted hazard ratio) × 100. Separate models were performed for all-cause, PCV7, PCV13 and PCV13-non-PCV7 serotype-specific IPD, and for Aboriginal and non-Aboriginal children., Results: Following introduction of universal PCV7 in 2005, rates of PCV7 serotype and all-cause IPD in unvaccinated children declined 89.5% and 61.4%, respectively, to be similar to rates in vaccinated children. Among non-Aboriginal children, VEs for 3 doses were 94.2% (95%CI: 81.9-98.1) for PCV7 serotype-specific IPD, 85.6% (95%CI: 60.5-94.8) for PCV13-non-PCV7 serotype-specific IPD and 80.1% (95%CI: 59.4-90.3) for all-cause IPD. There were no statistically significant differences between the VEs for 3 doses and for 1 or 2 doses against PCV13 and PCV13-non-PCV7 serotype-specific IPD, or between Aboriginal and non-Aboriginal children., Conclusion: Our population-based cohort study demonstrates that >90% coverage in the first year of a universal 3 + 0 PCV program provided high population-level protection, predominantly attributable to strong herd effects. The size of the cohort enabled calculation of robust dose-specific VE estimates for important population sub-groups relevant to vaccination policies internationally., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Unlabelled: There have been few surveys of Streptococcus pneumoniae and Neisseria meningitidis carriage in sick or frail elderly people who, with the very young, comprise the group who are at highest risk for pneumococcal disease. We studied pneumococcal carriage among participants in a pneumococcal immunisation study in the frail elderly., Methods: Subjects aged >or=60 years were recruited from a large tertiary referral hospital in Sydney, Australia. Nose and throat swabs were collected at the time of enrolment and 12 months after immunisation., Results: Before immunisation, only 1 of 315 participants was identified as a nasal carrier of S. pneumoniae; another was identified as throat carrier of N. meningitidis. None of the participants examined after immunisation was carrying either S. pneumoniae or N. meningitidis., Conclusion: The low rate of pneumococcal carriage in this population of hospitalised elderly patients was unexpected. The most likely reason is that long-term carriage is rare in this population and suggests that pneumococcal disease primarily follows recent acquisition of S. pneumoniae types not associated with carriage., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Aim: To investigate attitudes, perceptions and knowledge of elderly hospital patients in regard to vaccination in general and pneumococcal vaccination in particular., Setting: A hospital-based patient survey in Sydney, Australia., Participants: Patients aged 60 years and older who are admitted to selected wards in an 800-bed tertiary referral hospital in Sydney, Australia., Methods: A face-to-face interview administered to 200 inpatients., Results: Approximately half (49%) of the patients had a positive attitude to vaccination whereas 59% had less positive perception. There were 35% of the patients who were unvaccinated against influenza and pneumococcal disease. Positive perception (OR 2.9, 95% C.I.=1.3-6.5) and attitude (OR 4.4, 95% C.I.=2.0-9.4) significantly predicted vaccination with both vaccines. Similarly the odds of receiving pneumococcal vaccination for those who had a more positive attitude and more correct knowledge were significant (OR=2.3, 95% C.I.=1.0-5.4; OR=2.7, 95% C.I.=1.1-6.8). We explored reasons for non-vaccination. Physician recommendation was listed as an important factor by patients., Conclusions: Positive perception and attitude towards vaccination are significant factors associated with immunisation status. For the pneumococcal vaccination, having influenza vaccination is related to pneumococcal vaccination.

Objectives: To describe the serotypes, incidence and morbidity of invasive pneumococcal disease in urban New South Wales., Design: Prospective laboratory surveillance., Setting: Microbiology laboratories and hospitals in the Sydney, Hunter and Illawarra Statistical Divisions of NSW, June 1997 to May 1999., Results: 1270 cases were identified in two years. Incidence of disease was highest in those aged < 2 years (96.4 per 100,000; 95% CI, 83.7-107.9) and > or = 85 years (100.1 per 100,000; 95% CI, 81.8-121.3). Incidence of disease increased significantly from the age of 60 years, compared with low rates in those aged 5-59 years. Underlying diseases predisposing to pneumococcal infection increased with age, from 4% (< 2 years) to 60% (> or = 65 years). A seven-valent conjugate vaccine would have covered 84.8% of serotypes in those aged 0-14 years, falling to 69% in those > or = 15 years. Penicillin resistance was significantly higher in the < 5 years group (19.0%) than in older people (14.6%)., Conclusions: Incidence of invasive pneumococcal disease was higher in this study using active surveillance than in previous Australian studies. An effective sevenvalent conjugate pneumococcal vaccine could prevent more than 80% of cases in children aged < 5 years.

Childhood pneumococcal disease is associated with substantial morbidity and mortality, but total disease burden is more difficult to measure than for invasive disease caused by Haemophilus influenzae type b (Hib). A safe, effective seven-valent conjugate pneumococcal vaccine will be available in Australia by early 2001, and will certainly be indicated for high-risk groups and purchased in the private sector, as was Hib vaccine. The status of this vaccine on the Australian Standard Vaccination Schedule will require more detailed consideration of the burden and serotype distribution of pneumococcal disease in Australian children and the vaccine's likely cost-effectiveness. Postmarketing surveillance will be particularly important.

The proceedings of the Pneumococcal Disease in Australia Workshop, held on 26-27 March 1999 are presented in this report. The world-wide epidemiology of the pneumococcus, with its predilection for the very young and the very old, differs between the developing and the developed world, and between indigenous and non-indigenous populations. Sources of data on pneumococcal disease in each of the Australian States, clinical aspects of invasive and non-invasive disease, and the role of the public health laboratory in surveillance of serotypes and antimicrobial sensitivity, both nationally and over time, were discussed at the Workshop. Polysaccharide pneumococcal vaccines are recommended for those over 65 years of age and for at-risk groups, but are supplied free of charge only in Victoria and for indigenous Australians over 50 years of age. Children will require conjugate vaccines, which are likely to be licensed in the United States of America early in 2000. In Australia indigenous children, especially in rural areas, will be the priority group for conjugate vaccines.

Objective: Few data are available on invasive disease due to Streptococcus pneumoniae in representative Australian childhood populations. This study aimed to determine the age-specific incidence of invasive pneumococcal disease in Sydney children., Methodology: Population-based prospective study where isolates of Streptococcus pneumoniae from normally sterile sites were identified through an established laboratory surveillance network. Isolates came from children aged under 15 years living within the boundaries of Central, Eastern. Southern, Western and South-western Sydney Area Health Services from 1 July 1991 to 30 June 1996., Results: Invasive pneumococcal disease was identified in 320 children during a 5-year period, of whom 193 (60%) were under 2 years of age. The incidence per 100,000 children was 12.7 per 100,000 (95% CI: 11.4-14.2/100,000) under 15 years; 31.7 (95% CI 28.1-35.7) under 5 years, and 45.5 (95% CI 38.9-53.3) under 2 years. The incidence of pneumococcal meningitis in children aged under 2 years was 10.5 per 100,000 (95% CI: 7.4-14.5/100,000)., Conclusions: The incidence of childhood invasive pneumococcal disease in Sydney was stable during 1991-96 and comparable to rates reported from other industrialized countries. There was no evidence of any change in pneumococcal disease incidence with reduction in invasive Haemophilus influenzae type b (Hib) disease following introduction of Hib immunization.

Pneumococci are a leading cause of bacterial meningitis and bacteraemia, as well as pneumonia, otitis media and sinusitis in childhood. These organisms recently have shown a dramatic increase in antibiotic resistance. Penicillin-resistant pneumococci are of special concern as they are often resistant to other unrelated antibiotics. This is of particular significance to Aboriginal children who have among the highest rates of pneumococcal infection in the world. Laboratories should now test all invasive pneumococcal isolates for penicillin and third generation cephalosporin resistance. Local treatment guidelines are required for pneumococcal infections, especially for meningitis, taking into account the prevalence of resistant strains within the community. At present, penicillin and amoxycillin remain the drugs of choice for pneumococcal infections, with the exception of meningitis where initial empirical therapy must be with a third generation cephalosporin. Judicious antibiotic use, which avoids over-prescribing and unnecessary use of broad-spectrum agents, improved living standards in underprivileged communities and introduction of an effective conjugate vaccine, able to reduce the rates of pneumococcal infection and hopefully colonization, may limit the spread of resistant strains.

Objective: To document the pattern and sequelae of invasive pneumococcal infection in hospitalized children., Methodology: Retrospective review of Streptococcus pneumoniae (Sp) isolates from normally sterile sites from 1981 to 1992 at three paediatric centres in Sydney for demographic data, spectrum of disease, predisposing conditions, mortality, and sequelae from meningitis., Results: Four hundred and thirty-one episodes in 417 patients were identified. Foci of infection were: meningitis, 34%; pneumonia, 29%; bacteraemia without apparent focus, 30%; and other foci, 7%. Sixty-one per cent of all cases and 64% of cases with meningitis were less than 2 years old. Predisposing conditions were present in 37%, were significantly more common in patients over age 2 years and were more common with foci other than meningitis. Overall mortality was 6.6% whereas the mortality for those with meningitis was 8%. Neurological sequelae were identified in 34% of previously normal children, and severe hearing loss occurred in 11.5%., Conclusions: The high morbidity and mortality from invasive pneumococcal infection in children justifies further evaluation of preventive strategies.