Laboratory surveillance of invasive pneumococcal disease in Australia in 2001 to 2002--implications for vaccine serotype coverage.

This paper reports the results of comprehensive laboratory surveillance of invasive pneumococcal disease (IPD) in Australia during 2001 and 2002. The 7-valent conjugate pneumococcal vaccine was introduced for high risk paediatric groups, including Indigenous children, in late 2001. Of 1,355 isolates from non-Indigenous children, 86 per cent belonged to serotypes and 93 per cent to serogroups represented in the 7-valent pneumococcal conjugate vaccine. Thirteen per cent and 24 per cent of isolates had reduced susceptibility to penicillin and erythromycin, respectively and of these, more than 99 per cent belonged to serogroups represented in the 7-valent vaccine. Of the 1,504 isolates from non-Indigenous adults, 96 per cent belonged to serotypes included in the 23-valent polysaccharide vaccine; 14 per cent and 15 per cent had reduced susceptibility to penicillin and erythromycin, respectively and more than 95 per cent of these belonged to serotypes included in the 7-valent conjugate vaccine. In Western Australia and the Northern Territory (the only states for which Indigenous status was consistently available), there were 29 cases of IPD in Indigenous children, of which 21 were due to 7-valent vaccine serotypes in 2001, compared with 24 cases, including 10 due to vaccine serotypes, in 2002. This represents a statistically significant increase in the proportion of total isolates due to non-vaccine serotypes (chi2 = 3.93, p = 0.048) following the introduction of the 7-valent conjugate vaccine, principally due to serotypes 7F and 12F. The number of episodes due to penicillin resistant isolates decreased from nine in 2001 to two in 2002. Ninety per cent of isolates from Indigenous adults were included in the 23-valent polysaccharide vaccine and six per cent and five per cent had reduced susceptibility to penicillin and erythromycin, respectively. Conjugate pneumococcal vaccines can be expected to reduce the incidence of IPD due to vaccine serotypes in vaccinated children and potentially, their adult contacts. It may also impact favourably on the incidence of IPD due to penicillin and erythromycin resistant strains. Continued surveillance of both serotype distribution and antibiotic susceptibility are required 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.     

Invasive Streptococcus pneumoniae in children, Malawi, 2004-2006

Of 176 invasive Streptococcus pneumoniae isolates from children in Malawi, common serotypes were 1 (23%), 6A/B (18%), 14 (6%), and 23F (6%). Coverage with the 7-valent pneumococcal conjugate vaccine (PCV) was 39%; PCV10 and PCV13 increased coverage to 66% and 88%, respectively. We found chloramphenicol resistance in 27% of isolates and penicillin nonsusceptibility in 10% (by using meningitis breakpoints); all were ceftriaxone susceptible.     

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.     

Fluoroquinolone and other antimicrobial resistance in invasive pneumococci, Hong Kong, 1995-2001

We determined the susceptibilities of 265 invasive isolates of pneumococci obtained during 1995 to 2001 in Hong Kong to 11 antimicrobial agents and their serotypes. Overall, 62.6% isolates were susceptible to penicillin, 20% were intermediately resistant, and 17.4% were resistant. The overall prevalence of levofloxacin resistance (MIC > or = 8 microg/mL) was 3.8% but increased to 15.2% among the penicillin-resistant isolates. All levofloxacin-resistant isolates were clonally related; had reduced susceptibility to penicillin, cefotaxime, and clarithromycin; and were derived from adults > or = 50 years of age. Of the penicillin-nonsusceptible pneumococci, 90% from children < or = 5 years of age and 54.8% from persons of all ages were of serotypes that are included in the 7-valent pneumococcal conjugate vaccine; 93.5% from children < or = 5 years of age and 93% from persons of all ages were of serotypes that are included in the 23-valent polysaccharide vaccine.     

2017-2019年苏州地区儿童肺炎链球菌血清分型及耐药特征

目的 了解苏州大学附属儿童医院呼吸道感染儿童肺炎链球菌菌株的血清型分布及耐药特征,为制定肺炎链球菌相关疾病的治疗和预防接种策略提供参考.方法 采用乳胶凝集和荚膜肿胀试验对肺炎链球菌菌株进行血清分型,采用E-test法检测菌株对多种抗生素的耐药性.结果 2017年1月-2019年7月共收集3 652株肺炎链球菌,主要来自...     

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 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.     

Non-invasive pneumococcal disease and antimicrobial resistance: vaccine implications

We reviewed laboratory data on non-invasive pneumococcal isolates reported from all diagnostic laboratories in Scotland during the period 1988-99. Of 4491 isolates from hospitalized patients, 654 (64.7%) were from sputum, 79 (7.8%) from the nasopharynx and 278 (27.5%) from other superficial sites. The serogroups included in the 23-valent polysaccharide vaccine caused 96.9% of all non-invasive disease in all age groups. The 7-, 9-, and 11-valent conjugated vaccine serogroups were responsible for 87-94%, 85-93%, 74-81% and 75-84% of non-invasive disease respectively in age groups < 2 years, < or = 5 years, > or = 65 years and all ages. The coverage of non-susceptible penicillin and erythromycin non-invasive isolates was > 99% and > 95% with the 23-valent polysaccharide and 7-11-valent conjugate vaccines respectively. The eight most common serogroups were 23, 9, 6, 19, 14, 3, 15 and 11 (in descending order). The serogroups associated with antimicrobial resistance in non-invasive disease were similar to those found in invasive disease. The finding of a similar serogroup distribution in both invasive and non-invasive disease (regardless of the site of clinical isolate), is consistent with serogroups colonizing non-sterile sites and having the potential to invade. The availability of conjugated vaccines reinforces the importance of systematic surveillance to determine accurately and regularly the coverage of pneumococcal serogroups and types causing both invasive and non-invasive disease.     

Serotype distribution and antimicrobial susceptibility of S. pneumoniae causing invasive disease in Thai children younger than 5 years old, 2000-2005

In order to predict the potential benefit of pneumococcal conjugate vaccines (PCV), we evaluated the serotype coverage of the 7-, 9-, 11- and 13-valent PCV over the isolates causing invasive pneumococcal disease (IPD) in Thai children. One hundred and fifteen Streptococcus pneumoniae isolates from sterile sites in children younger than 5 years old between 2000 and 2005 were serotyped. The coverages of 7-, 9-, 11-, and 13-valent PCV were 69%, 73.8%, 73.8% and 85.7% in children younger than 2 years, and 73.9%, 77.4%, 77.4% and 87.8% in children younger than 5 years of age, respectively. 69.6% and 22.6% of the isolates were non-susceptible to penicillin and cefotaxime. 7-valent PCV covered 89% and 100% of penicillin and cefotaxime non-susceptible isolates.     

Tracking drug-resistant Streptococcus pneumoniae in Oregon: an alternative surveillance method.

With the emergence of drug-resistant Streptococcus pneumoniae, community-specific antimicrobial susceptibility patterns have become valuable determinants of empiric therapy for S. pneumoniae infections. Traditionally, these patterns are tracked by active surveillance for invasive disease, collection of isolates, and centralized susceptibility testing. We investigated whether a simpler and less expensive method aggregating existing hospital antibiograms--could provide community-specific antimicrobial susceptibility data. We compared 1996 active surveillance data with antibiogram data from hospital laboratories in Portland, Oregon. Of the 178 S. pneumoniae active surveillance isolates, 153 (86% [95% confidence interval (CI) = 80% to 91%]) were susceptible to penicillin. Of the 1,092 aggregated isolates used by hospitals to generate antibiograms, 921 (84% [95% CI = 82%-87%]) were susceptible to penicillin. With the exception of one hospital's erythromycin susceptibility results, hospital-specific S. pneumoniae susceptibilities to penicillin, cefotaxime, trimethoprim-sulfamethoxazole, and erythromycin from the two methods were statistically comparable. Although yielding fewer data than active surveillance, antibiograms provided accurate, community-specific drug-resistant S. pneumoniae data in Oregon.     

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 New Zealand 1998-2005: capsular serotypes and antimicrobial resistance

Isolates from 3903 cases of invasive pneumococcal disease (IPD) were referred to the national reference laboratory over the 8 years, 1998-2005, as part of the laboratory-based surveillance of this disease in New Zealand. All isolates were serotyped and their antimicrobial susceptibility was tested. The incidence of IPD was highest in young children, with an average annual incidence of 100.8/100,000 in infants aged <2 years. There were changes in the prevalence of several of the serotypes during the 8-year period. Overall the seven serotypes included in the 7-valent pneumococcal conjugate vaccine, 4, 6B, 9V, 14, 18C, 19F and 23F, were the most common serotypes and accounted for 80.9% of the disease in infants aged <2 years. There was no overall change in penicillin resistance or non-susceptibility during the 8 years, and rates were 7.1% and 17.1%, respectively, in 2005. In contrast, cefotaxime and erythromycin resistance increased to reach 3.1% and 12.2%, respectively, by 2005.     

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.     

Streptococcus pneumoniae serotype 4 outbreak in a home for the aged: report and review of recent outbreaks.

OBJECTIVE: To describe a pneumonia outbreak caused by Streptococcus pneumoniae among residents of a home for the aged and to review contemporary pneumococcal outbreaks. DESIGN: Epidemiological investigation. METHODS: S pneumoniae isolates were serotyped and analyzed by pulsed-field gel electrophoresis. Paired sera were tested for antibodies to pneumococcal surface adhesin A protein (PsaA, a 37-kDa cell-wall protein). Pneumococcal outbreaks reported in the last decade in English were reviewed. RESULTS: Pneumonia developed in 18 of 200 residents. In 11 (61%), a pneumococcal etiology was demonstrated. S pneumoniae, serotype 4, was isolated from the blood cultures of 3 patients; all isolates were indistinguishable by pulsed-field gel electrophoresis. Pneumococcal involvement was established in 2 by sputum culture and latex agglutination of parapneumonic fluid and in 6 others by a twofold rise in optical density of serum antibody reactive to PsaA. Pneumococcal immunization had not previously been received by any patient; mortality was 22%. No additional cases were noted following administration of pneumococcal vaccine and antibiotic prophylaxis with penicillin or erythromycin. Twenty-six outbreaks of invasive pneumococcal disease since 1990 were reviewed. Twelve occurred in the United States, and serotypes 23F, 14, and 4 accounted for 8 (67%) of 12 outbreaks. All confirmed serotypes in US outbreaks are included in the 23-valent vaccine. More than one half of pneumococcal outbreaks worldwide involved elderly persons in hospitals or long-term-care facilities. CONCLUSIONS: A pneumococcal pneumonia outbreak occurred among unvaccinated residents of a residential facility for the aged. Institutionalized elderly persons are at risk of outbreaks of pneumococcal disease and should be vaccinated.     

Serotypes/groups distribution and antimicrobial resistance of invasive pneumococcal isolates: implications for vaccine strategies

Based on the invasive pneumococcal isolates referred to reference laboratories in Scotland in 1988-99, we identified the distribution of serotypes/groups and their antimicrobial resistance patterns in order to evaluate the coverage of polysaccharide and the new pneumococcal conjugate vaccines. A total of 5659 invasive isolates were included. Of these, 5124 (90.5%) were blood isolates, 308 (5.5%) were CSF isolates, 143 (2.5%) were blood and CSF and 84 (1.5%) were other normally sterile isolates. The most prevalent 11 serotypes/groups were 14, 9, 19, 6, 23, 1, 3, 4, 7, 8 and 18, in numerical order. These accounted for 84% of total serotypes/groups. The serotypes/groups included in the 23 and 14-valent polysaccharide vaccines accounted for 96% and 88% of all isolates. Both vaccines accounted for 98% of penicillin non-susceptible and 100% of erythromycin non-susceptible isolates. The 7, 9, and 11-valent conjugate vaccines covered 61, 68 and 80% of invasive isolates respectively. The coverage of these vaccines was substantially higher in youngest age group with 84, 86 and 93% of invasive isolates in children < 2 years included in the 7, 9 and 11-valent conjugate vaccines compared with 58, 64 and 77% in adults > or = 65 years of age. The serotype/group distribution of invasive isolates in Scotland varied from year to year over the period 1993-9. The coverage of the 23-valent vaccine remained above 95% in each year but the coverage of the 7, 9 and 11-valent conjugate vaccines showed more marked fluctuation with coverage as low as 53, 60 and 75% in some years. Continued surveillance of invasive pneumococcal isolates is required to inform the development of appropriate vaccine strategies to prevent pneumococcal disease in Scotland.     

Invasive pneumococcal disease in Australia, 2003.

There were 2,174 cases of invasive pneumococcal disease (IPD) notified to the National Notifiable Diseases Surveillance System (NNDSS) in Australia in 2003; a rate of 10.9 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 two years (98.8 cases per 100,000 population). Enhanced surveillance for IPD in 2003 was carried out in all states and territories, providing additional data on 1,842 (85%) of all notified cases. Rates of IPD in Indigenous Australians were three times the rate in non-Indigenous Australians. There were 125 deaths attributed to IPD resulting in an overall case fatality rate of 6.8 per cent. Seventy-one percent of all pneumococcal isolates serotyped were serotypes in the seven-valent conjugate vaccine and 91 per cent were serotypes in the 23-valent polysaccharide pneumococcal vaccine. The clinical presentation and risk factors for IPD varied between Indigenous and non-Indigenous cases and non-vaccine serotypes occurred more frequently among Indigenous children and adults. Data from three years of surveillance indicate an early impact of the 7-valent vaccine in the target population.     

Nasopharyngeal carriage of Streptococcus pneumoniae in healthy children: implications for the use of heptavalent pneumococcal conjugate vaccine

We assessed the prevalence of Streptococcus pneumoniae serotypes in the nasopharynx of healthy children, antimicrobial susceptibility patterns, risk factors for carriage, and the coverage of heptavalent pneumococcal conjugate vaccine. In 2,799 healthy infants and children, the S. pneumoniae carrier rate was 8.6% (serotypes 3, 19F, 23F, 19A, 6B, and 14 were most common). Most pneumococci (69.4%) were resistant to one or more antimicrobial classes. The rate of penicillin resistance was low (9.1%); macrolide resistance was high (52.1%). Overall, 63.2% of the isolates belonged to strains covered by the heptavalent pneumococcal vaccine. This percentage was higher in children <2 years old (73.1%) and in those ages 2-5 years (68.9%). Sinusitis in the previous 3 months was the only risk factor for carrier status; acute otitis media was the only risk factor for the carriage of penicillin-resistant S. pneumoniae. Most isolated strains are covered by the heptavalent conjugate vaccine, especially in the first years of life, suggesting that its use could reduce the incidence of pneumococcal disease.     

Pneumococcal disease and vaccination in the Americas: an agenda for accelerated vaccine introduction.

This piece summarizes the presentations and discussions at a meeting on pneumococcal disease surveillance in the Americas that was held in Mexico City, Mexico, on 2 November 2004. This meeting was organized by the Pan American Health Organization (PAHO) and the Pneumococcal Vaccines Accelerated Development and Introduction Plan (PneumoADIP) of the Global Alliance for Vaccines and Immunization (GAVI). The meeting participants reviewed the status of pneumococcal disease surveillance in the Region of the Americas, estimates of the burden of pneumococcal disease, the distribution of Streptococcus pneumoniae serotypes that cause invasive disease, the status of pneumococcal vaccine introduction, health economic analyses, and financial issues related to vaccine introduction. The meeting participants also worked to identify the next steps for generating the critical information needed to help make decisions on pneumococcal vaccine introduction. Coordinated pneumococcal disease surveillance for the Region of the Americas dates back to the 1993 establishment by PAHO of the Regional System for Vaccines (RSV) project for surveillance of bacterial meningitis and pneumonia, including pneumococcal disease. Surveillance data from the RSV indicate that the distribution of major serotypes in the Americas has been stable over time (but that antibiotic resistance is increasing), with serotype 14 being the leading serotype isolated in most countries participating in RSV. Based on local serotype data from six of the RSV countries (Argentina, Brazil, Chile, Colombia, Mexico, and Uruguay), the 7-valent vaccine would cover 65% of serotypes, the 9-valent vaccine would cover 77%, and the 11-valent vaccine would cover 83%.     

Aggregated antibiograms and monitoring of drug-resistant Streptococcus pneumoniae

Community-specific antimicrobial susceptibility data may help monitor trends among drug-resistant Streptococcus pneumoniae and guide empiric therapy. Because active, population-based surveillance for invasive pneumococcal disease is accurate but resource intensive, we compared the proportion of penicillin-nonsusceptible isolates obtained from existing antibiograms, a less expensive system, to that obtained from 1 year of active surveillance for Georgia, Tennessee, California, Minnesota, Oregon, Maryland, Connecticut, and New York. For all sites, proportions of penicillin-nonsusceptible isolates from antibiograms were within 10 percentage points (median 3.65) of those from invasive-only isolates obtained through active surveillance. Only 23% of antibiograms distinguished between isolates intermediate and resistant to penicillin; 63% and 57% included susceptibility results for erythromycin and extended-spectrum cephalosporins, respectively. Aggregating existing hospital antibiograms is a simple and relatively accurate way to estimate local prevalence of penicillin-nonsusceptible pneumococcus; however, antibiograms offer limited data on isolates with intermediate and high-level penicillin resistance and isolates resistant to other agents.     

Summary of invasive pneumococcal disease burden among children in the Asia-Pacific region

Invasive pneumococcal disease (IPD) burden is significant in the Asia-Pacific region. This review describes the epidemiology and Streptococcus pneumoniae (SP) serotype distribution of IPD in children in the Asia-Pacific region from studies published from 1999 to 2010. IPD incidence varies widely in Asia-Pacific countries depending on the method of surveillance, the population studied, and the time period. Incidences are highest for younger children, with rates near 100–200 cases per 100,000 children aged <1 or 2 years. Incidences of preventable disease are estimated to be 6–200 cases per 100,000. Heptavalent pneumococcal conjugate vaccine (PCV7) serotype coverage shows a very wide range over the Asia-Pacific region. Ten countries have high vaccine serotype coverage (>70%), and six countries have low vaccine serotype coverage (<50%). The majority of SP serotypes in children with IPD in most countries in the Asia-Pacific region are susceptible to penicillin (intermediate and resistant <50%); a few countries have SP serotypes with high level resistance to penicillin (intermediate and resistant >50%). Japan, Taiwan, and Thailand have high PCV7 serotype coverage. Countries with low pneumococcal resistance to antimicrobials have shown increasingly higher nonsusceptibility with time. National vaccination programmes that include PCV7, 10-valent pneumococcal conjugate vaccine (PCV), or 13-valent PCV would significantly affect IPD burden in children aged <5 years in the Asia-Pacific region, as well as the burden of penicillin-nonsusceptible IPD.