Antimicrobial resistance and serotypes of nasopharyngeal strains of Streptococcus pneumoniae in Chinese children with acute respiratory infections

This prospective, multicentre, nasal carriage study in Chinese children with upper respiratory infection was carried out over the period from 2000 to 2002. Overall, the prevalence of pneumococcal carriage was 24.9%. Antimicrobial susceptibility tests were performed for 887 isolates of Streptococcus pneumoniae of which 33.5% were intermediately susceptible to penicillin and 6.4% were resistant. Multidrug resistance was very common. Pneumococcal strains (n = 625) were serotyped, showing 72.2% were covered by the 23-valent pneumococcal polysaccharide vaccine and 57.6% by the seven-valent pneumococcal conjugate vaccine. Serogroups 19 and 23 were significantly associated with penicillin resistance, which is increasing in China. Erythromycin, tetracycline and sulphamethoxazole/trimethoprim cannot be recommended as first-line treatments for respiratory tract infection as in some other developing countries. These features of serotype distribution are of importance for surveillance in the era of the new conjugate vaccine. In particular, these features will allow for documentation of serotype replacement after the introduction of widespread vaccination.     

Antimicrobial resistance of Streptococcus pneumoniae isolated in Taiwan: an island-wide surveillance study between 1996 and 1997

Between August 1996 and July 1997, 550 clinically significant Streptococcus pneumoniae isolates were collected from 14 geographically separate laboratories in Taiwan. These isolates were serotyped and MICs were determined by agar dilution. Among serotypes covered by the 23-valent vaccine, types 19F, 19A, 23F, 23A and 6B dominated, comprising 255 isolates; among non-vaccine serotypes, types 35, 39, 34, 13 and 31 dominated, comprising 118 isolates. Of the 550 isolates, 310 (56.4%) were resistant to penicillin G (MIC 0. 12 mg/L), 238 (43.3%) with intermediate resistance (MIC 0.12-1 mg/L) and 72 (13.1%) with high-level resistance (MIC 2 mg/L). Most non-susceptible pneumococci were of serotypes 19F and 23F; non-susceptible isolates of these serotypes were distributed across all of Taiwan. Fourteen other antibiotics were tested; 83% of the isolates were resistant to tetracycline, 78% to azithromycin, 74% to erythromycin, 54% to clindamycin and 23% to chloramphenicol. Thus, macrolides can no longer be used as first line agents to treat pneumococcal infections in Taiwan. Multi-resistance (isolates resistant to three or more chemically unrelated antibiotics) was found in each serotype or group, but mostly in types 19F and 23F. The emergence of such strains complicates antibiotic selection, but both types are covered by the 23-valent vaccine, as were 82% of the isolates from blood and eight of the nine from cerebrospinal fluid. Good antibiotic control and appropriate use of this vaccine may improve the current problem in Taiwan, especially for the elderly.     

Serotype distribution and antimicrobial resistance of Streptococcus pneumoniae isolates from pediatric patients in Singapore

One hundred eighty Streptococcus pneumoniae strains isolated from children at a pediatric hospital in Singapore from 1997 to 1999 were serotyped and their antimicrobial susceptibility patterns were determined. Sixty-three percent of the isolates were resistant to penicillin. Significantly large numbers of the strains investigated were resistant to trimethoprim-sulfamethoxazole (87.8%), tetracycline (71.7%), erythromycin (67.8%), and chloramphenicol (40%). Penicillin and multidrug resistance was mostly associated with the frequently isolated S. pneumoniae isolates of serotypes (serotypes 19F, 23F, 6B, and 14). Isolates of serotype 19F, the serotype most commonly encountered in Singapore (41.1%), had the highest prevalence of penicillin (78.4%) and multidrug resistance (94.6%). Most of the invasive S. pneumoniae isolates (8 of 17; 47. 1%) were of serotype 14.     

北京市东城区221名1~12岁健康儿童肺炎链球菌携带状况研究

目的 了解1~12岁健康儿童鼻咽部肺炎链球菌携带情况,及该菌血清型、耐药情况,为制定防治策略提供参考依据。 方法 2010年10月至2011年6月,选取北京市东城区221名1~12岁健康儿童,每2个月采集鼻咽拭子标本1次,进行肺炎链球菌培养、血清分型及耐药性检测。 结果 1~12岁健康儿童肺炎链球菌累计携带率为57.47%;分离到32个血清型共220株肺炎链球菌,7价肺炎球菌结合疫苗的血清型覆盖率为36.82%,23价肺炎链球菌荚膜多糖疫苗的血清型覆盖率为64.55%;耐药菌株占3.64%。 结论 1~12岁健康儿童存在着较高肺炎链球菌疾病的风险,有必要建立科学的监测体系,研制出适合国情的肺炎链球菌疫苗。     

Serotype distribution and antimicrobial resistance patterns of Streptococcus pneumoniae isolated from children in China younger than 5 years

This study examined the epidemiology, antibiotic susceptibility, and serotype distribution of Streptococcus pneumoniae associated with invasive and noninvasive pneumococcal disease in children in China. A total of 451 clinical isolates from children (age, <5 years) were collected from 8 cities from January 2005 to December 2006, including 31 isolated from invasive disease. In vitro susceptibility to 14 antimicrobial agents was determined by the agar dilution method. Among all isolates tested, 64.3% were resistant to penicillin, and for invasive isolates, the resistance rate was 55.2%. Isolates from Wuhan and Nanjing showed the highest prevalence of penicillin resistance (89.6% and 85%), followed by those from Shenzhen (72.4%) and Chengdu (56.7%). Multidrug resistance rates to tetracycline, erythromycin, and clindamycin reached 90%. The 6 most common serotypes were 19F, 19A, 14, 6B, 23F, and 15. These accounted for 80.7% of the isolates. Resistance to penicillin varied among the 6 leading serotypes, ranging from 20% in serotype 15 to 87.3% in serotype 19F. Each of the 8 cities had different serotype distribution. The potential coverage by 7-, 10-, and 13-valent pneumococcal conjugate vaccine were 63.6%, 64.8%, and 79.6%, respectively.     

肺炎链球菌对红霉素耐药机制的研究

目的 研究北京地区肺炎链球菌对红霉素的耐药机制。方法 收集本院1998－1999年分离的对红霉素耐药的肺炎链球菌116株,采用“荚膜肿胀”技术进行血清分型,聚合酶链反应（PCR）检测对红霉素耐药的基因erm/mef,脉冲场凝胶电泳（PFGE)客青霉素结合蛋白（PBP）基因印迹技术追踪菌株之间的同源性。结果 116株红霉素耐药株的血清型主要为23F（30.0%),6A（19.0%),19F（13.8%),15（7.8%),23A（5.2%)。95.7%的青霉素不敏感株同时也耐红霉素;85％的菌株表现为MLS表型,即同时耐克林霉素;86．4％的红霉素耐药株具有erm基因,6％的菌株同时有erm和mef基因,1．7％的菌株只有mef基因,4．2％未能检测到erm或mef基因。PFGE发现2种耐药克隆：1个是青霉素耐药的血清型为23F的克隆株,另1个是青霉素敏感而红霉素耐药的、血清型为6A的克隆株。结论 核糖体突变（erm基因编码）是北京地区肺炎链球菌耐红霉素的主要机制,2种耐药克隆值得关注。     

Antimicrobial susceptibility and serotype distribution of Streptococcus pneumoniae causing meningitis in Egypt, 1998-2003

OBJECTIVES: To determine the antimicrobial susceptibility and serotype distribution of 205 isolates of Streptococcus pneumoniae, collected from the CSF of meningitis patients identified between 1998-2003, during sentinel meningitis surveillance in Egypt. METHODS: Antimicrobial susceptibility was evaluated against six antibiotics using disc diffusion and Etest methods. Serotyping was performed by latex agglutination and the Quellung test. RESULTS: Forty-nine percent of all isolates were found to be non-susceptible to penicillin (46% intermediate, MIC range 0.12-1.0 mg/L; 3% resistant, MIC = 2.0 mg/L), and 6% of the isolates were non-susceptible to ceftriaxone (5% intermediate, MIC = 1.0 mg/L; 1.3% resistant, MIC >/= 2 mg/L). Resistance rates for tetracycline and trimethoprim/sulfamethoxazole were high (52 and 59.7%, respectively), but those for erythromycin and chloramphenicol were lower (11 and 9%, respectively). Five serotypes (6B, 1, 19A, 23F and 6A) accounted for 37% of the total isolates. Ten isolates (5%) were non-typeable. Overall, 29 and 42% of serotypes were represented in the 7- and 11-valent conjugate vaccines, respectively. However, vaccine coverage for children <2 years was 38 and 56% for the 7- and 11-valent, respectively. CONCLUSIONS: Resistance to penicillin may be increasing among S. pneumoniae strains causing meningitis in Egypt, and a moderate proportion of these strains are not covered by current pneumococcal conjugate vaccines. In addition to intensifying education efforts about judicious use of antibiotics, laboratory-based surveillance for other forms of invasive pneumococcal disease, especially pneumonia, is needed before decisions can be made regarding the most effective vaccines for control of this disease in Egypt.     

Antimicrobial susceptibility of Streptococcus pneumoniae: serotype distribution of penicillin-resistant strains in Spain.

This study examined the resistance to penicillin, tetracycline, erythromycin, and chloramphenicol of 318 pneumococcal strains isolated in Spanish hospitals from blood or cerebrospinal fluid of patients during 1979 to 1981. The serotypes of these strains were determined to discover whether a correlation between serotype and patterns of antibiotic resistance could be found. Seven and nine patterns of resistance were found in strains isolated from blood and cerebrospinal fluid, respectively; tetracycline was the most frequent pattern, followed by tetracycline associated with chloramphenicol. A random distribution of serotypes which was similar to the general distribution of serotypes was found for resistance to tetracycline and chloramphenicol, but penicillin-resistant strains were confined to seven serotypes. Thirty-six strains of penicillin-resistant pneumococci isolated from sources other than blood or cerebrospinal fluid were also serotyped. They represented the same serotypes, suggesting that serotype distribution among penicillin-resistant strains could be a manifestation of local epidemiological factors.     

Streptococcus pneumoniae in community-acquired respiratory tract infections in Spain: the impact of serotype and geographical, seasonal and clinical factors on its susceptibility to the most commonly prescribed antibiotics. The Spanish Surveillance Group for Respiratory Pathogens

Resistance of Streptococcus pneumoniae to antimicrobial agents shows geographical variation and also depends on serotype, patient age and sample origin. Factors affecting antibiotic resistance in S. pneumoniae were studied from results of a multicentre susceptibility study of 12 antimicrobial agents, carried out in 14 Spanish hospitals between May 1996 and April 1997. The most frequent serotypes were serotypes 6 (14.8%), 19 (11.8%), 23 (10.5%), 3 (9.9%), 9 (8.0%), 14 (8.0%), 15 (3.9%) and 11 (3.2%); 9.6% of isolates were not typeable. The remaining 25 serotypes constituted 20.2% of strains. Penicillin resistance was more prevalent in serotypes 14 (88%), 23 (66%), 9 (62%) and 6 (57%), whereas erythromycin resistance was more prevalent in serotypes 6 (68.5%), 15 (61.4%), 14 (49.5%), 19 (42.7%) and 23 (39.3%). Serotypes 6 and 19 were the serotypes most commonly isolated from both children and adults, although with different proportions (24.0% and 19.2% of isolates from children were serotype 6 and 19, respectively, with the corresponding figures for isolates from adults being 13.6% and 11.5%, respectively). The rates of resistance of pneumococcal strains to penicillin and cefuroxime were significantly higher in strains from children than in those from adults (resistance to penicillin, 50.4% in children and 37.0% in adults; resistance to cefuroxime, 62.4% in children and 45.6% in adults). There was significantly more resistance to erythromycin in middle ear isolates (48.9%) than in blood isolates (27%). The prevalence of resistance to beta-lactams showed a seasonal pattern, with higher rates in summer and winter, proportional to the magnitude of resistance. Susceptibility to macrolides did not vary seasonally. Our results stress the relative importance that geographical, temporal (seasonality), patient (sample type, origin, age group) and bacterium-related (serotype) factors have on the variations in susceptibility observed among different pneumococcal clinical isolates.     

Serotype distribution of penicillin-resistant pneumococci and their susceptibilities to seven antimicrobial agents

A total of 229 clinical isolates of Streptococcus pneumoniae recovered from 225 patients were serotyped and tested for susceptibility to penicillin G, ampicillin, mezlocillin, cefazolin, erythromycin, clindamycin, chloramphenicol, and sulfamethoxazole-trimethoprim. Of all the isolates, 48 (21.0%) showed intermediate resistance and 17 (7.4%) showed resistance to penicillin G. Penicillin-resistant strains had higher minimal inhibitory concentrations of ampicillin, mezlocillin, and cefazolin than did penicillin-susceptible strains. Resistance to erythromycin and clindamycin was rare (1.3 and 0.9%, respectively). Of the isolates, 8.7% were resistant to sulfamethoxazole-trimethoprim, and all were susceptible to chloramphenicol. Penicillin resistance was associated with 13 serotypes. Serotypes 14, 19F, 19A, and 23F were both highly prevalent and frequently penicillin resistant.     

肺炎链球菌呼吸道感染分离株的耐药性

目的：研究肺炎链球菌呼吸道感染分离株的耐药性及其传播情况。方法：肺炎链球菌分离株进行药物敏感试验和血清学分型,并结合BOX PCR、脉冲场电泳(pulse—field gel electrophoresis,PFGE)和青霉素结合蛋白基因(penicilin binding proteingene,pbp)指纹等分子生物学方法分析菌株间亲缘关系。结果：呼吸道感染分离株128株中有青霉素低度耐药株(penicillin intermediated Streptococcus pneurnoniae,PISP)10株,未发现青霉素高度耐药株(penicillin resistant Streptococcus pneumoniae,PRSP)。lll株存活菌株分属25种血清型,主要为23F、3、19F、14、9V、6A、6B等。9株存活PISP中有6种PFGE谱型,2株PFGE谱型相同菌株的耐药谱和血清型相仿;2株不同PFGE谱型菌株pbp指纹相似,对青霉素和头孢曲松敏感性相似;上述呼吸道感染分离PISP中未发现与世界主要流行耐药克隆代表株DNA指纹或pbp基因相似菌株。结论：上述肺炎链球菌呼吸道感染分离株青霉素耐药率尚低,存在青霉素耐药克隆和基因的传播,其中尚未发现世界主要流行耐药克隆。     

Genetic structure of Streptococcus pneumoniae isolated from children in a tertiary care university hospital, in Korea, 1995 to 2005

We investigated the genetic structure of Streptococcus pneumoniae isolated from Korean children prior to the use of heptavalent pneumococcal conjugate vaccine (PCV7). A total of 278 pneumococcal isolates were obtained from invasive (n = 77) and noninvasive (n = 201) specimens from children < 5 years of age that visited the Seoul National University Children's Hospital between 1995 and 2005; these samples were serotyped. Two hundred seventy-eight isolates were characterized by multilocus sequence typing, antibiotic susceptibility pattern testing with the E-test. The common serotypes were 19F (22.7%), 23F (19.1%), 19A (14.4%), 6B (11.2%), 6A (8.3%), 14 (5.4%), and 9V (4.3%); these 7 serotypes accounted for 85.3% of the 278 isolates. The isolates belonged to 23 serotypes and 81 sequence types (STs) (including 48 newly discovered STs). The eBURST analysis showed 7 clonal complexes (CCs). CC271 was the main CC of serogroup 19; CC81 and CC3115, serotype 6A; CC81 and CC880, serotype 23F; CC90, serotype 6B; CC166, serotype 9V; and CC554, serotype 14. Nonsusceptibility rates to penicillin and erythromycin among the invasive isolates were 9.1% and 94.8%, respectively. The resultant database may be useful for postvaccine surveillance.     

大连地区儿童肺炎链球菌耐药及血清分型研究

目的研究大连地区住院儿童感染肺炎链球菌（SP）的耐药性及其血清分型。方法 SP菌株均从5岁以下儿童患者鼻咽抽吸物中分离。血清分型通过多重PCR方法鉴定,药敏试验通过E-test方法来判断,而耐药基因ermB及mefA/E则由PCR方法来检测。结果从2010年7月到2013年6月,共分离得到131例SP。药敏结果显示所有的131例菌株对红霉素以及克林霉素全部耐药,大约有39.8%的菌株对青霉素G不敏感,而所有的菌株则均对左氧氟沙星和万古霉素敏感。此外,有129例（98.5%）属于多种耐药菌株。血清分型结果显示本地区SP血清型以19F（28.2%）、19A（19.1%）、6B（17.6%）及23F（14.5%）为主。且在这些血清型中的SP中,青霉素不敏感肺炎链球菌（PNSP）对阿莫西林、头孢曲松及头孢噻肟的不敏感性要显著高于青霉素敏感肺炎链球菌（PSSP）（P〈0.05）。7价疫苗（PCV7）和13价疫苗（PCV13）覆盖的血清型分别占68.7%和87.8%。此外,49株（37.4%）单独携带ermB基因,而82株（62.6%）同时携带ermB和mefA/E两种耐药基因。结论大多数分离的SP对青霉素G仍然相对敏感,所有菌株对左氧氟沙星和万古霉素敏感。本地区SP血清型以19F、19A、6B及23F为主。鉴于19A血清型的高流行率,引入PCV13更能有效地预防儿童肺炎链球菌的感染和控制耐药菌株传播。     

Epidemiological and molecular characterization of invasive Streptococcus pneumoniae isolated following introduction of 7-valent conjugate vaccine in Kinki region,Japan, 2008–2013

Streptococcus pneumoniae is one of the most common bacteria causing community-acquired pneumonia and meningitis. The use of 7-valent pneumococcal conjugate vaccine (PCV7) has reduced the incidence of pneumococcal disease while changing pneumococcal population through herd immunity and non-vaccine pneumococci replacement. This study investigated molecular epidemiologic characteristics of pneumococcal strains in the Kinki region of Japan from 2008 to 2013. A total of 159 invasive pneumococcal isolates were characterized by serotyping, antibiotic susceptibility testing, PCR analysis of penicillin-binding protein genes, multilocus sequence typing (MLST), and pulsed-field gel electrophoresis (PFGE). In adult populations, pediatric PCV7 introduction decreased isolates expressing PCV7 serotypes via herd immunity and increased isolates expressing non-PCV7 serotypes. The rate of penicillin resistance and isolates with alterations in all three pbp genes was higher in PCV7 type isolates than in non-PCV7 type isolates. In MLST analysis, all of serotype 19F isolates were of the same sequence type, ST236, which is the antimicrobial-resistant clone Taiwan^19F-14, and the majority of serotypes 23F and 19A isolates were of ST1437 and ST3111 respectively, which are the predominant clones of antimicrobial-resistant pneumococci in Japan. In PFGE profiles, serotype 6B-ST2224, serotype 19F-ST236, serotype 19A-ST3111, and serotype 23F-ST1437 formed six separate clusters composed of genetically identical strains, and genetically identical serotype 22F-ST433 formed two different clusters between the pre- and post-PCV7 period. The results of molecular analysis suggest the spread and persistence of these identical antimicrobial resistant clones in the Kinki region and genetic changes of epidemic clone serotype 22F-ST433 before and after pediatric PCV7 introduction.     

Changes in nasopharyngeal carriage and serotype distribution of antibiotic-resistant Streptococcus pneumoniae before and after the introduction of 7-valent pneumococcal conjugate vaccine in Hong Kong

This study assessed the changes in serotype distribution and antibiotic resistance of Streptococcus pneumoniae isolates in children before and after introduction of the 7-valent pneumococcal conjugate vaccine (PCV7) in Hong Kong. Nasopharyngeal specimens were collected from 1978 and 2211 children (ages, 2 to 6 years) attending day care centers or kindergartens in period 1 (1999-2000) and period 2 (2009-2010), respectively. Carriage of PCV7 serotypes decreased from 12.8% to 8.6% (P < 0.01). The relative contribution of PCV7 serotypes 14 and 18C had decreased, whereas that for non-PCV7 serotypes 19A, 6A, 6C, 23A, and 15B had increased. In period 2, PCV7 penetration rate (at least 1 dose) for children aged 2, 3, 4, and 5 years was 43%, 35.7%, 26.7%, and 20.4%, respectively. In multivariate analysis, PCV7 use was the only independent variable associated with fewer PCV7 serotype carriages (odds ratio 0.5; P = 0.001). In period 2, high rates of dual penicillin/erythromycin nonsusceptibility were found in serotypes 6B (77.3%), 14 (100%), 19F (100%), 23F (78%), 19A (75%), 6A (87.8%), 6C (59.3%), and 23A (78.9%).     

Relationship between capsular type, penicillin susceptibility, and virulence of human Streptococcus pneumoniae isolates in mice

We examined the relationship between penicillin susceptibility, peritoneal virulence in Swiss mice, and capsular type in a selection of 122 clinical Streptococcus pneumoniae isolates belonging to 24 serotypes. Regardless of the serotype, all 32 virulent strains were susceptible to penicillin, and all 41 strains with diminished susceptibility or resistance to penicillin were avirulent. The remaining 49 strains were both susceptible to penicillin and avirulent, irrespective of the serotype. On the basis of their capsular type and pathogenic behavior, strains fell into one of four groups. In the group consisting of serotypes 1, 3, and 4 (n = 16), strains were predominantly virulent (81.3%), and all were penicillin susceptible. In the serotype 6 group (n = 32), the frequency of virulence was significantly lower (34.4 versus 81.3%, P = 0.002), and strains were predominantly penicillin susceptible (71.9%). In the group composed of serotypes 9, 14, 19, and 23 (n = 50), all strains were avirulent, and 56% had decreased susceptibility (n = 12) or resistance to (n = 16) penicillin. The fourth group was heterogenous, as it pooled 24 strains of 15 different serotypes; in this group the frequency of virulence was 33.3%, and strains were predominantly penicillin susceptible (83.3%). These data point to a complex relationship between penicillin susceptibility and virulence in mice but do not entirely separate these characteristics from the role of the capsular type. The possibility that the mechanisms conferring penicillin resistance are related to those leading to a loss of virulence is supported by these findings.     

Serotype distribution and antimicrobial resistance of invasive Streptococcus pneumoniae isolates in Bulgaria before the introduction of pneumococcal conjugate vaccine

The 10-valent pneumococcal conjugate vaccine (PCV10) was introduced as a mandatory vaccine in Bulgaria in April 2010. We report on the serotype distribution and the antimicrobial resistance of 222 invasive Streptococcus pneumoniae isolates collected from all age groups before the introduction of PCV10. PCV7, PCV10, and PCV13 covered 43.7, 59.9, and 78.8% of all invasive pneumococcal strains, and 64.2, 79.1, and 89.6% of isolates involving children less than 5 years of age. Penicillin resistance was found in 30.1% of the isolates responsible for meningitis and in 5.0% of isolates responsible for other invasive infections. Overall, erythromycin resistance was found in 19.4% of all invasive strains. The erm(B) was the most prevalent pneumococcal macrolide resistance genotype (63.2%) and dual mechanisms of both genes the erm(B) and mef(E) were detected in 15.8% of 19 erythromycin resistant isolates during the period 2006-2010. The prevalence and spread of serotypes 19F, 6B, and 19A during the last period may have contributed to the high predominance of erm(B) genotype in comparison of mef genotype, which was predominant in our country among erythromycin-resistant isolates before 2005. Continuing surveillance is required after the recent introduction of PCV10 in order to observe future developments of any serotype changes in the Bulgarian population, as well as surveillance of antimicrobial susceptibility of invasive S. pneumoniae isolates.     

Serotype and antimicrobial resistance patterns of Streptococcus pneumoniae isolated from Taiwanese children: comparison of nasopharyngeal and clinical isolates

This report describes the serotypes and antimicrobial resistance patterns of 860 strains of Streptococcus pneumoniae isolated from nasopharyngeal (NP) carriers and clinical specimens collected from Taiwanese children during the years 1997 to 2003. The 6 most common serotypes/groups were 23F, 19F, 6B, 14, 6A, and 3. These accounted for 652/716 (91.1%) of the NP and 131/144 (91.0%) of the clinical isolates. Serotype 23F was the most common isolate in the NP carriers (25.7%, 184/716). Serogroup14 was most common in the clinical isolates (29.2%, 42/144) and the most frequent invasive isolate (43.4%, 33/76). It was more frequently associated with invasive infection than all other serotypes/groups (odds ratio = 7.2; 95% confidence interval, 4.16-12.46; P < .0001). Resistance to macrolides was high in all serotypes/groups, which ranged from 70% to 97%. Resistance to penicillin varied among the 6 leading serotypes/groups, ranging from 3% in serogroup 3 to 99% in serotype 19F. Serotype 23F was most likely to be multidrug resistant to penicillin, macrolides, and chloramphenicol compared with all others (107/150 [71%] versus 105/461 [23%], P < .0001). The potential coverage by the pentavalent and heptavalent vaccines was 83% for all isolates, but was significantly lower for NP than clinical isolates (81% versus 92%, P< .01). These findings provide baseline data to compare trends in the distribution of pneumococcal serotypes and antibiotic resistance patterns with the introduction of childhood pneumococcal vaccination in Taiwan and other countries.     

Antibiotic susceptibility and serotypes of Streptococcus pneumoniae isolates from Hungary

OBJECTIVE: Hungary has reported one of the highest incidences of penicillin resistance in Streptococcus pneumoniae in Europe since the 1970s and is still cited accordingly. However, since the end of the 1990s the resistance of pneumococci in Hungary has not been investigated. In this study we assessed the current situation, particularly to establish whether the incidence of resistance is increasing and if this could be related to the spread of specific strain types. METHODS: Isolates of S. pneumoniae (n = 304) were collected by five diagnostic laboratories in Hungary in 2000-2002. Their identity was confirmed and their susceptibilities to 16 antibiotics were determined by the agar dilution method according to NCCLS guidelines. Representative strains were serotyped (n = 112). RESULTS AND CONCLUSIONS: We found significantly lower resistance rates for penicillin compared with the data previously reported from Hungary, but the intermediate resistance was high, at 37%. Macrolide resistance was a bigger problem ( approximately 40% for erythromycin), although there was full susceptibility to telithromycin. The strains with the highest MICs were isolated from carriers and young children. The fluoroquinolones were very effective, especially moxifloxacin and gatifloxacin. There was full susceptibility to vancomycin and linezolid. We found inconsistencies with previous reports in the survey of the resistance and identification of S. pneumoniae in the country. The serotype distribution of the isolates showed a much greater diversity than had previously been reported; however, there was correlation between serotype and resistance.     

Antibiotic resistance and serotypes of Streptococcus pneumoniae from patients with community-acquired pneumococcal disease.

From August 1978 to December 1981, 200 Streptococcus pneumoniae strains isolated from adult patients with pneumococcal disease were tested for susceptibility to penicillin G, erythromycin, clindamycin, tetracycline, and chloramphenicol by disk diffusion. Minimal inhibitory concentrations (MICs) were determined by agar dilution and broth dilution. The sources (numbers) of these isolates were blood (111), cerebrospinal fluid (30), sputum (26), pleural fluid (16), and miscellaneous (17). Of the 200 strains, 18 were partially resistant (MIC, 0.1 to 1 micrograms/ml) and 2 were resistant to penicillin. A total of 144 (72%) strains were tetracycline resistant, 87 of which had MICs of greater than or equal to 64 micrograms/ml. Ninety (45%) isolates exhibited various degrees of chloramphenicol resistance, with MICs ranging from 16 to 64 micrograms/ml. Five strains were resistant to erythromycin and clindamycin. Eleven penicillin-resistant strains were also resistant to chloramphenicol and tetracycline. Twenty-one different serotypes were encountered among the 120 typed strains studied. The most prevalent serotypes, in order of frequency, were 3, 1, 5, 19, 8, 6, 9, and 4, representing approximately two-thirds of the total number of isolates serotyped. These findings clearly indicate the need to perform antibiotic susceptibility testing in all cerebrospinal fluid isolates and other clinical significant isolates.