Invasive pneumococcal disease in Australia, 2002.

There were 2,271 cases of invasive pneumococcal disease (IPD) notified to the National Notifiable Diseases Surveillance System in Australia in 2002; a rate of 11.5 cases per 100,000 population. The notification rate varied between states and territories and by geographical region with the highest rates in the north of the country. Invasive pneumococcal disease was reported most frequently in children aged less than five years (57.3 per 100,000 population). Enhanced surveillance for IPD in 2002 was carried out in all states and territories, providing additional data on 1,929 (85%) of all notified cases. Rates of IPD in Indigenous Australians were 2.7 times the rate in non-Indigenous Australians. The clinical presentation of IPD was most commonly pneumonia (44%) and bacteraemia (35%). There were 175 deaths attributed to IPD resulting in an overall case fatality rate of 9.2 per cent. Forty-two per cent of all cases had a recognised risk factor for IPD. Seventy-five per cent of all pneumococcal isolates serotyped were serotypes in the seven-valent conjugate vaccine and 93 per cent were serotypes in the 23-valent polysaccharide pneumococcal vaccine. The clinical presentation and rates of risk factors varied between Indigenous and non-Indigenous cases and non-vaccine serotypes occurred more frequently among Indigenous children and adults.     

Invasive pneumococcal disease in Australia, 2001.

There were 1,681 cases of invasive pneumococcal disease (IPD) notified to the National Notifiable Diseases Surveillance System in Australia in 2001; a rate of 8.6 cases per 100,000 population. The notification rate varied between states and territories and by geographical region with the highest rates in the north of the country. Pneumococcal disease was reported most frequently in children aged less than 5 years (47.3 cases per 100,000 population). Enhanced surveillance for IPD was carried out in the Northern Territory, Western Australia, South Australia, Victoria, Tasmania and metropolitan areas of New South Wales, encompassing 72 per cent of the population and providing additional data on 86 per cent of all notified cases. Enhanced surveillance data revealed high rates of pneumococcal disease in Indigenous Australians. Rates of IPD in Indigenous children aged less than 5 years were as high as 483 cases per 100,000 population in the Northern Territory. The clinical presentation of IPD was most commonly pneumonia (56%) and bacteraemia (36%). There were 125 deaths attributed to IPD resulting in an overall case fatality rate of 8.6 per cent. More than half (54%) of all cases had a recognised risk factor for IPD. Eighty-six per cent of serotypes identified in non-indigenous children compared with only 55% of serotypes in Indigenous children were in the 7-valent vaccine. Antibiotic susceptibility testing showed reduced susceptibility to penicillin in 12 per cent, and to third generation cephalosporins in 5 per cent of isolates. These are the first national data available on IPD in Australia and will assist in evaluating the impact of the newly introduced conjugate vaccine and guide overall pneumococcal vaccine strategies.     

Invasive pneumococcal disease in Australia, 2004

There were 2,375 cases of invasive pneumococcal disease (IPD) notified to the National Notifiable Diseases Surveillance System in Australia in 2004; a notification rate of 11.8 cases per 100,000 population. The rate varied between states and territories and by geographical region with the highest rates in the Northern Territory. Invasive pneumococcal disease was reported most frequently in children aged less than 5 years (55.4 cases per 100,000 population). Enhanced surveillance for IPD was carried out in all states and territories, in 2004, providing additional data on 2,023 (85%) cases. The overall rate of IPD in Indigenous Australians was 3.2 times the rate in non-Indigenous Australians. There were 154 deaths attributed to IPD resulting in an overall case fatality rate of 7.6 per cent. Rates of IPD in the Indigenous and non-Indigenous under 2-year-old population were similar in 2004 (91.5 and 93.6 cases per 100,000 population, respectively) following a targeted introduction of the 7-valent pneumococcal conjugate vaccine (7vPCV) in mid-2001 for Indigenous infants and children. Serotypes of isolates were identified from 80 per cent of all notified cases, with 72 per cent of isolates belonging to serotypes represented in the 7vPCV and 91 per cent in the 23-valent polysaccharide pneumococcal vaccine (23vPPV). Comparison of serotypes in the 7vPCV target population showed that the rate of IPD due to 7vPCV serotypes decreased by 74 per cent between 2001-02 and 2003-04. Of 216 isolates with reduced penicillin susceptibility, 83 per cent belonged to pneumococcal serotypes in the 7vPCV and 95 per cent in the 23vPPV.     

Invasive pneumococcal disease in Australia, 2005

Enhanced surveillance for invasive pneumococcal disease (IPD) was carried out in all Australian states and territories in 2005 with comparative data available since 2001. There were 1,680 cases of IPD notified to the National Notifiable Diseases Surveillance System in Australia in 2005; a notification rate of 8.3 cases per 100,000 population. The rates varied between states and territories and by geographical region with the highest rates in the Northern Territory, the jurisdiction with the largest proportion of Indigenous people. Invasive pneumococcal disease was reported most frequently in those aged 85 years or over (41 cases per 100,000 population) and in 1-year-old children (36.5 cases per 100,000 population). Enhanced data provided additional information on 1,015 (60%) of all notified cases. The overall rate of IPD in Indigenous Australians was 8.6 times the rate in non-Indigenous Australians. There were 126 deaths attributed to IPD resulting in an overall case fatality rate of 7.5%. While the rate of IPD in the Indigenous under 2-year-old population decreased from 219 cases per 100,000 population since targeted introduction of the 7-valent conjugate pneumococcal vaccine (7vPCV) in 2001, the rate in 2005 (94 cases per 100,000 population) was significantly greater than in non-Indigenous children (20.4 cases per 100,000 population). Rates of disease in all children aged less than 2 years, caused by serotypes in the 7vPCV decreased by 75% between 2004 and 2005 as a result of the introduction of a universal childhood 7vPCV immunisation program. Significant decreases in IPD caused by 7vPCV serotypes also occurred in the 2-14 years and 65 years or over age groups. There is no evidence of replacement disease with non-vaccine serotypes. Serotypes were identified in 90% of all notified cases, with 61% of disease caused by serotypes in the 7vPCV and 88% caused by serotypes in the 23-valent polysaccharide pneumococcal vaccine (23vPPV). Reduced penicillin susceptibility remains low and reduced susceptibility to 3rd generation cephalosporins is rare.     

Invasive pneumococcal disease in Australia, 2006

Enhanced surveillance for invasive pneumococcal disease (IPD) was carried out in all Australian states and territories in 2006 with comprehensive comparative data available since 2002. There were 1,445 cases of IPD notified to the National Notifiable Diseases Surveillance System in Australia in 2006; a notification rate of 7 cases per 100,000 population. The rates varied between states and territories and by geographical region with the highest rates in the Northern Territory, the jurisdiction with the largest proportion of Indigenous people. Invasive pneumococcal disease was reported most frequently in those aged 85 years or over (30.8 cases per 100,000 population) and in children aged one year (26.5 cases per 100,000 population). There were 130 deaths attributed to IPD resulting in an overall case fatality rate of 9%. The overall rate of IPD in Indigenous Australians was 4.3 times the rate in non-indigenous Australians. The rate of IPD in the under two years population continued to fall in 2006, but the rate in Indigenous children (73 cases per 100,000 population) was significantly greater than in non-Indigenous children (21 cases per 100,000 population). The rates of disease caused by serotypes in the 7-valent pneumococcal conjugate vaccine (7vPCV) decreased between 2002 and 2006 by 78% in children aged under two years as a result of the introduction of a universal childhood 7vPCV immunisation program. Significant decreases in IPD caused by 7vPCV serotypes also occurred in the 2-14 years and 65 years or over age groups. Rates of disease caused by non-7vPCV in the same periods were little changed. Serotypes were identified in 94% of all notified cases, with 43% of disease caused by serotypes in the 7vPCV and 85% caused by serotypes in the 23-valent polysaccharide pneumococcal vaccine (23vPPV). The number of invasive pneumococcal isolates with reduced penicillin susceptibility remains low and reduced susceptibility to third generation cephalosporins is rare.     

Invasive pneumococcal disease in north Queensland, 2001.

This report provides information on the 93 locally-acquired cases of invasive pneumococcal disease (IPD) notified in children and adults in north Queensland in 2001. Indigenous people represented 38 (41%) cases. Almost half (45) of all cases were in children under 15 years of age, 20 (44%) of these were in children less than 2 years of age and 20 (44%) in Indigenous children. Five severe cases of IPD occurred, all in non-indigenous children under 2 years of age. Nine (10%) of the isolates from cases, mainly in young children, had some level of resistance to penicillin. Pneumococcal vaccination programs (including the Indigenous 'elderly and at-risk' adult program and the paediatric 'Indigenous and medically at-risk' conjugate vaccine program) are in place in Queensland although the vaccine is not currently funded for other at-risk groups. If vaccine recommendations had been adhered to in a timely fashion, two of the cases in children and one third (16) of the cases in adults that occurred in 2001 could potentially have been prevented.     

Invasive pneumococcal disease among children in Victoria.

This study analysed notification data from the first year of enhanced surveillance of invasive pneumococcal disease (IPD) in Victoria (1 July 2001 - 30 June 2002), with a focus on risk factors for infection and vaccination status among children under five years of age. Overall, there were 397 notifications (8.2 per 100,000 population), 131 (33%) were children under five years of age. The highest notification rates were among those aged less than two years (72.6 per 100,000 population). Among children aged less than five years: bacteraemia without a primary focus of infection was the most common clinical presentation (64%); 89 per cent were hospitalised with the median length of stay being three days; four children (3%) died. There were 107 cases of a known serotype, 92% (n = 98) were either in or closely related to those included in the 7-valent conjugate pneumococcal vaccine (7vPCV). Most cases (98%) were not eligible for free 7vPCV under the currently funded program in Victoria. Only one child had been vaccinated. The results from the first year of enhanced IPD surveillance in Victoria suggest consideration should be given to extending the publicly funded program to include all children under two years of age.     

Invasive pneumococcal disease in Singapore children

INTRODUCTION: Our retrospective study examined community-acquired invasive pneumococcal disease (IPD) in children admitted to KK Women's and Children's Hospital, Singapore. METHODS: All pneumococcal isolates from sterile sites from 1997 to 2004 were surveyed. RESULTS: There were 147 positive pneumococcal isolates with a mean age of 45 months. The estimated incidence of IPD was 13.6 per 10(5) children under 5 years old. Diagnoses at presentation were: Pneumonia 63.3% (included 14.3% empyema), bacteremia 17%, meningitis 15.6% (included 2.8% meningitis and pneumonia), 4.1% others. The morbidity rate was 25.2%, mortality rate was 6.1%. Antibiotic resistance was: Penicillin 44%, ceftriaxone 15%, erythromycin 62%, trimethoprim-sulfamethoxazole 67%. A separate serotype analysis (n=93, 63%) showed that the current 7valent pneumococcal conjugate vaccine (PCV7) would cover 78.1% of vaccine serotypes and 89% of vaccine-related serotypes for children under 5 years old.     

Invasive pneumococcal disease in the Kimberley, 1995-2001

OBJECTIVE: To describe the epidemiology of invasive pneumococcal disease (IPD) in the Kimberley and examine whether cases could have been prevented by vaccination. DESIGN: Prospective case series of IPD cases from 1 January 1995 to 31 December 2001. SETTING: The Kimberley region of far north-western Australia. SUBJECTS: Seventy IPD cases in 37 men and 33 women aged 5 months to 90 years. Aboriginal people comprised 90% (63/70) of cases. MAIN OUTCOME MEASURES: Demographic, clinical and microbiological characteristics of IPD cases. Proportion of cases caused by vaccine-preventable serotypes. IPD incidence in the Kimberley. RESULTS: Pneumonia and bacteraemia were the commonest clinical presentations. Of IPD cases, 15% (children) and 67% (adults) had a risk factor for IPD. The case fatality rate was 13%. Of cases, 46% (95% confidence interval (CI) 35-58%) were caused by serotypes covered by an age-appropriate vaccine. Of the 26 cases eligible for pneumococcal vaccination, only 4 (16%) had been appropriately vaccinated. IPD incidence in Aboriginal people aged 15 years and over declined from 97.8/100,000 person years (95% CI 56.5-139.1) in 1997 to 38.1/100,000 person years (95% CI 22.5-53.9) in 2001. CONCLUSIONS: The significant proportion of cases caused by vaccine-preventable serotypes and that was, therefore, preventable underscores the importance of pneumococcal vaccination.     

Laboratory surveillance of invasive pneumococcal disease in Australia, 2003 predicting the future impact of the universal childhood conjugate vaccine program.

A comprehensive invasive pneumococcal disease (IPD) laboratory surveillance program was carried out in Australia in 2003. This program provided data on the prevalence of pneumococcal serotypes and antimicrobial resistance. There were 1,995 isolates tested with 34 per cent (683) from children aged less than five years and 27 per cent (535) from the elderly aged more than 65 years. One thousand eight hundred and sixty were isolates from blood, 79 from CSF and 56 from other sterile sites. In young children, 84 per cent of isolates were a serotype and 92 per cent a serogroup in the 7-valent pneumococcal conjugate vaccine (7vPCV). Of penicillin resistant isolates in children less than five years of age 85 per cent and 98 per cent were a serotype and serogroup in the 7vPCV respectively. When the universal 7vPCV vaccine program in young children is introduced in 2005, a proportion of cases of IPD should also be prevented in young adults (estimated reduction of 54 cases annually) and elderly Australians (an estimated reduction of 110 cases annually) as a result of improved herd immunity. Pneumococcal serotypes with higher rates of penicillin resistance (19F, 14 and 6B) were more prevalent in the elderly than in young children. In contrast, erythromycin resistance was more common in children less than five years of age (24%) compared to the elderly (15%). The predominant serotype with erythromycin resistance in Australia was serotype 14 and thus there is likely to be a major reduction in erythromycin resistance as a result of 7vPCV vaccination. Continued surveillance of pneumococcal serotype distribution and antibiotic susceptibility will be essential in order to identify serotype replacement by non-vaccine serotypes and to monitor the overall impact of current and future vaccine programs on invasive pneumococcal disease in Australia, not only in young children but also in other age groups.     

Invasive pneumococcal disease in children in the Community of Valencia, Spain

OBJECTIVE: Pneumococcal disease is an important cause of morbidity and mortality in children. The recent authorization of the heptavalent conjugate vaccine has increased interest in this disease. The objective of this study was to identify the epidemiological and clinical characteristics of this disease, as well as its outcome in the pediatric population of the Autonomous Community of Valencia. METHOD: Data were obtained from the medical records of children aged less than 15 years who were positive for pneumococcus isolation on admission to hospital between 1996 and 2000. All the public hospitals of the Autonomous Community of Valencia were included. Changes in incidence were evaluated by comparing rates and outcomes (sequelae and lethality) through frequency and age distribution. RESULTS: One hundred twenty-seven cases were registered, giving a mean annual rate of 3.89/105 inhabitants aged less than 15 years. The rate was 20.14 in children aged less than 2 years. A total of 29.1% of the children had previous health problems. The main clinical manifestations included sepsis/bacteremia (38%), pneumonia (31%) and meningitis (24%). At discharge sequelae were present in 10 children, 75% of whom were aged less than 2 years. Eight children died (6.3% lethality). CONCLUSIONS: In the period and region studied, pneumococcal infection was present mainly in children aged less than 2 years and in those with previous health problems. In the last few years, mortality has increased. Thus, inclusion of pneumococcal disease in the epidemiological surveillance system would be appropriate to achieve more precise estimations of its epidemiological patterns and to determine whether the conjugate vaccine represents a solution to the problems currently associated with this bacteria.     

Tuberculosis notifications in Australia, 2003.

The National Notifiable Disease Surveillance System (NNDSS) received 982 tuberculosis (TB) notifications in 2003, of which 947 were new cases, 33 were relapses and two were cases with unknown history. The incidence of TB in Australia has remained at a stable rate since 1985 and was 4.9 cases per 100,000 population in 2003. The high-incidence groups remain people born overseas and Indigenous Australians at 19.9 and 8.7 cases per 100,000 population, respectively. By contrast the incidence in non-Indigenous Australians was 0.9 per 100,000. Comparison of the 2003 TB notification data against the performance indicators set by National Tuberculosis Advisory Committee highlights that enhanced TB control measures should be considered among these high-risk groups.     

Invasive pneumococcal infections in Canadian children, 1998-2003: implications for new vaccination programs

BACKGROUND: We conducted active surveillance for invasive pneumococcal disease to assess the serotype and antibiotic resistance patterns in Canada prior to universal infant immunization programs, in most provinces. METHODS: Active surveillance was conducted by the 12 centres of the Canadian Paediatric Society's Immunization Monitoring Program, Active (IMPACT). This report includes children 16 years of age and younger with S. pneumoniae isolated from a normally sterile site, in 1998-2003. RESULTS: During six years of surveillance, 1,868 eligible cases were reported. The 7-valent pneumococcal conjugate vaccine (PCV7) matched 79% of isolates, including 84% from 6-23 month olds and 80% from 2-5 year olds. The proportion of isolates matched by PCV7 significantly decreased over the surveillance period from 81% in 1998 to 73% in 2003 (p = 0.005). The 23-valent polysaccharide vaccine (PPS) matched 90% of isolates from children 2 years or older. Penicillin non-susceptibility rate was stable at 16% of isolates. Cefotaxime/ceftriaxone resistance rate was 5% and limited to penicillin-resistant isolates. Serotypes found in PCV7 accounted for 89% of penicillin-resistant isolates (100% including cross-reacting types 6A and 19A). CONCLUSION: PCV7 matched three quarters of the isolates from young children as immunization programs began; therefore some program failures are inevitable. Children > or =5 years with predisposing conditions need the broader protection of 23-valent PPS vaccine and special attention from providers to ensure receipt. The rate of penicillin resistance remained steady over the last six years. The majority of isolates non-susceptible to penicillin are found in PCV7.     

Invasive pneumococcal disease associated with high case fatality in India

ObjectiveTo study the seroepidemiology and antimicrobial resistance pattern of invasive pneumococcal disease (IPD) in older subjects who are admitted to hospitals in India.Study Design and SettingProspective surveillance of IPD in patients older than 18 years in seven large academic teaching hospitals in India from 1993 to 2008. All subjects who had Streptococcus pneumoniae isolated from normally sterile body fluids or were antigen positive in cerebrospinal fluid, ascitic fluid, and pleural fluid were identified as IPD cases in the study. Serotype/group (STG) and minimum inhibitory concentration for penicillin, chloramphenicol, co-trimoxazole (trimethoprim–sulfamethoxazole), erythromycin, and cefotaxime were determined.ResultsA total of 1,037 adult subjects with suspected invasive bacterial infection were recruited in the study. S pneumoniae was identified from normally sterile body fluids in 449 (43.3%) subjects. Meningitis (34.3%) and pneumonia (33.9%) were the most common clinical conditions associated with IPD. The case fatality was 25–30% across all age groups. Penicillin resistance was low at 2.7% overall. Resistance to co-trimoxazole was noted to be high and increasing in the study period from 42.9% in 1993 to 85.2% in 2008 (P = 0.001). The most common STG was serotype 1, which accounted for 22.9% of all isolates. The 23-valent pneumococcal polysaccharide vaccine covered 83.3% of the STGs (49/54; 95% confidence interval: 79.7, 96.9) for patients older than 60 years.ConclusionIPD continues to be a problem in India and is associated with high case fatality in spite of treatment in the hospital setting. Penicillin resistance is currently low in India. More than 80% of invasive STGs causing disease in the elderly in India are included in the formulation of polysaccharide pneumococcal vaccine.     

Invasive pneumococcal disease: association between serotype, clinical presentation and lethality

To ascertain the factors linked to invasive pneumococcal disease (IPD) caused by the different serotypes in the period 2007-2009, following the conjugate vaccine's inclusion in the childhood vaccination schedule, a total of 2013 IPD cases were reviewed. The mean annual incidence in this period was 10.74 cases per 100,000 inhabitans and the lethality was 8.8%. Overall serotype distribution displayed certain peculiarities, such as the high frequency of serotype 5. Serotype 3, male gender, sepsis and presence of risk factors were significantly associated with lethality. Vaccinated children under 5 years of age had a higher risk of disease due to serotype 19A. Serotype 8 was associated with the presence of underlying risk factors.     

Invasive pneumococcal disease in the Netherlands: Syndromes,outcome and potential vaccine benefits

With a retrospective study of invasive pneumococcal disease (IPD) surveillance data representative for ∼25% of the Dutch population (1275 hospitalized cases) over the period June 2004–June 2006 prior to the implementation of the 7-valent pneumococcal conjugate vaccine (PCV7), the aim was to provide baseline data on IPD for the interpretation of changes after implementation of conjugate vaccines. The IPD incidence peaked in 3–5-mnth-olds (63 cases per 100,000 persons yearly) and increased in adulthood, particularly after the age of 60 yrs, from 26 cases in 60–64-yr-olds to 97 cases per 100,000 in persons ≥90 yrs. Beyond the age of 4 yrs, 19% of IPD patients were immunocompromised, and this considerable percentage may have implications for vaccine efficacy.     

Creutzfeldt-Jakob disease surveillance in Australia January 1970 to December 2003.

The Australian National Creutzfeldt-Jakob Disease Registry (ANCJDR) was established by the Commonwealth Government in October 1993 in response to the recognition of four probable human pituitary hormone related Creutzfeldt-Jakob disease (CJD) deaths. An inquiry into CJD in Australia and the use of human pituitary hormones under the Australian Human Pituitary Hormone Program suggested the expansion of some activities of the Registry to include retrospective case ascertainment from 1 January 1970. In parallel with monitoring possible medically acquired (iatrogenic) cases of CJD, the ANCJDR prospectively monitors and investigates all suspect cases of transmissible spongiform encephalopathies occurring within the states and territories of Australia, including sporadic and familial, and the potential occurrence of variant CJD. The ANCJDR also actively participates in an international surveillance consortium. This brief report summarises methods of classification and ascertainment as well as current epidemiological findings and new surveillance techniques that are being adopted to improve case ascertainment.     

Invasive pneumococcal disease epidemiology and effectiveness of 23-valent pneumococcal polysaccharide vaccine in Alaska native adults

Alaska Native persons have age-adjusted invasive pneumococcal disease (IPD) rates two- to three-fold greater than non-Native Alaskans. To characterize IPD epidemiology and 23-valent polysaccharide pneumococcal vaccine (PPV-23) effectiveness in Alaska Native adults we reviewed IPD cases from Alaska-wide, laboratory-based surveillance. Sterile site isolates were serotyped. Vaccine effectiveness (VE) was estimated using the indirect cohort method. 394 cases (44.5 cases/100,000/year) occurred in 374 Alaska Native adults (36.0% aged > or =55 years). Underlying conditions included heavy alcohol use (65.7%), smoking (60.8%) and COPD (25.0%). Overall VE was 75% (95% confidence interval [CI]: 27%, 91%) but declined with increasing age; for persons > or =55 years (VE=<0; 95% CI: <0, 78%; p=0.713). Alaska Native adults experience high rates of IPD. The majority of IPD cases occurred in persons with underlying conditions and behaviors associated with increased risk of IPD in other populations. PPV-23 vaccine effectiveness was confirmed in younger Alaska Native adults but not among adults > or =55 years.