Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “serotype”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 739 records · Page 41Linked to original sources
PubMed2003

Analysis of molecular epidemiology of Chilean Salmonella enterica serotype enteritidis isolates by pulsed-field gel electrophoresis and bacteriophage typing.

Human Salmonella enterica serotype Enteritidis infections emerged in Chile in 1994. S. enterica serotype Enteritidis phage type 1 isolates predominated in the north, and phage type 4 isolates predominated in the central and southern regions. A study was planned to characterize this epidemic using the best discriminatory typing technique. Research involved 441 S. enterica serotype Enteritidis isolates, including clinical preepidemic samples (n = 74; 1975 to 1993) and epidemic (n = 199), food (n = 72), poultry (n = 57), and some Latin American (n = 39) isolates. The best method was selected based on a sample of preepidemic isolates, analyzing the discriminatory power (DP) obtained by phage typing and randomly amplified polymorphic DNA and pulsed-field gel electophoresis (PFGE) analysis. The highest DP was associated with BlnI PFGE-bacteriophage typing analysis (0.993). A total of 38 BlnI patterns (B patterns) were identified before the epidemic period, 19 since 1994, and only 4 in both periods. Two major clusters were identified by phylogenetic analysis, and the predominant B patterns clustered in the same branch. Combined analysis revealed that specific B pattern-phage type combinations (subtypes) disappeared before 1994, that different genotypes associated with S. enterica serotype Enteritidis phage type 4 had been observed since 1988, and that strain diversity increased before the expansion of S. enterica serotype Enteritidis in 1994. Predominant subtype B3-phage type 4 was associated with the central and southern regions, and subtype B38-phage type 1 was associated with the north (P < 0.0001). Food and poultry isolates matched the predominant S. enterica serotype Enteritidis subtypes, but isolates identified in neighboring countries (Peru and Bolivia) did not match S. enterica serotype Enteritidis subtypes identified in the north of Chile. The results of this work demonstrate that genetic diversity, replacement, and expansion of specific S. enterica serotype Enteritidis subtypes were associated with epidemic changes.

Animals↗
PubMed2004

Assessment of the epidemic potential of a new strain of rotavirus associated with the novel G9 serotype which caused an outbreak in the United States for the first time in the 1995-1996 season.

Rotavirus causes severe morbidity in developed countries and frequent deaths (> or = 500,000 per year) in less-developed countries. Historically, four serotypes--G1, G2, G3, and G4-have predominated; they are distinguished by one of two surface neutralization antigens (VP7). However, in 1983 and 1984 we described a new rotavirus serotype, designated G9, in five children hospitalized for diarrhea in Philadelphia, Pa. G9 rotavirus was not identified again in the Western Hemisphere until it caused ca. 50% of the rotavirus disease detected in Philadelphia in the 1995-1996 season. This outbreak allowed us to question whether a rotavirus strain completely new to a well-studied community would target either very young infants or older children, cause especially severe disease, or completely displace previously extant serotypes. We observed a significant excess of G9 infections in younger infants (especially in those < 6 months old) that might be attributed to the lack of G9-specific antibodies in mothers. Of further note, six of the seven oldest patients with rotavirus diarrhea were infected with the G9 strains (not significant). However, the age distribution of children with rotavirus did not differ over a 5-year study period regardless of the infecting serotype. Patients with diarrhea associated with G9 strains did not have disease more severe than that caused by the G1, G2, or G3 serotype. G9 strains did not displace the other serotypes but were virtually completely replaced by G1 or G2 serotypes in the three subsequent rotavirus seasons. We conclude that the abrupt appearance of this novel rotavirus serotype did not present a special threat to public health in the community.

Age Distribution↗
PubMed2004

Simple, rapid latex agglutination test for serotyping of pneumococci (Pneumotest-Latex).

The "gold standard" for epidemiological typing of Streptococcus pneumoniae (pneumococcus) is the capsular reaction test (Neufeld test) with antisera against the 90 pneumococcal polysaccharide capsules, i.e., serotyping. The method is labor intensive and requires a certain level of experience to be performed satisfactory, and thus it has been restricted for use in specialized reference or research laboratories. Surveillance of the serotype distribution of pneumococci that cause infections is important to secure an optimal composition of pneumococcal vaccines and to monitor antibiotic resistance in pneumococci. At Statens Serum Institut, a simple latex agglutination test for serotyping of pneumococci has been developed. The Pneumotest-Latex kit consists of 14 different pooled pneumococcus antisera (pools A to I and pools P to T) applied to latex particles. In a blind test of 352 isolates (with all 90 serotypes represented), 336 (95.5%) were typed or grouped correctly by the Pneumotest-Latex; in addition, 2 (7%) of 30 strains regarded as nontypeable or rough strains were serotyped, and the serotypes of these two isolates were confirmed by the capsular reaction test with type-specific antisera. The Pneumotest-Latex seems to be a sensitive method for serotyping or grouping of the majority of pneumococcal strains. By use of this ready-to-perform latex agglutination kit (Pneumotest-Latex), serotyping of pneumococci can gain more ground as a tool in prevention of pneumococcal diseases.

Bacterial Typing Techniques↗
PubMed2005

PCR analysis of egyptian respiratory adenovirus isolates, including identification of species, serotypes, and coinfections.

Eighty-eight adenovirus (Ad) isolates and associated clinical data were collected from walk-in patients with influenza-like illness in Egypt during routine influenza surveillance from 1999 through 2002. Respiratory Ad distributions are geographically variable, and serotype prevalence has not been previously characterized in this region. Serotype identity is clinically relevant because it predicts vaccine efficacy and correlates strongly with both clinical presentation and epidemiological pattern. Species and serotype identities were determined using several well-validated multiplex PCR protocols culled from the literature and supplemented with a few novel primer sets designed to identify rare types. The isolates included common species B1 serotypes (Ad3 and Ad7), common species C serotypes (Ad1, Ad2, and Ad5), the less common species B2 serotype Ad11, and three isolates of the rare species B1 serotype Ad16. Two isolates that appear to be variant Ad16 were also identified. Fifteen coinfections of multiple adenoviral types, primarily AdB/AdC and Ad3/Ad7 dual infections, were detected. The majority of these were verified using redundant PCR tests targeted at multiple genes. PCR is able to resolve coinfections, in contrast to traditional serum neutralization tests. PCR is also comparatively rapid and requires very little equipment. Application of the method allowed an inclusive determination of the serotypes found in the Egyptian respiratory sample set and demonstrated that coinfections are common and may play a previously unrecognized role in adenovirus pathogenesis, evolution, and epidemiology. In particular, coinfections may influence adenoviral evolution, as interserotypic recombination has been identified as a source of emerging strains.

Adenovirus Infections, Human↗
PubMed2005

Novel rotavirus VP7 typing assay using a one-step reverse transcriptase PCR protocol and product sequencing and utility of the assay for epidemiological studies and strain characterization, including serotype subgroup analysis.

Rotavirus is the most common cause of severe dehydrating gastroenteritis in infants. To date, 10 different serotypes of rotavirus have been identified in human stools. While four or five serotypes dominate, serotype circulation varies with season and geography. Since our laboratory has been involved in the development of a multivalent rotavirus vaccine, it is important to identify the serotypes of rotavirus encountered during our clinical trials. We have developed methodologies for the molecular identification of rotavirus strains based on VP7 gene segment sequence. A 365-bp reverse transcriptase PCR product was generated from the VP7 gene segment using a pair of novel degenerate primers. All serotypes tested (both animal and human) yielded an identically sized product after amplification. Sequencing of these products is performed using truncated versions of the original primers. The sequence generated is compared against a database of rotavirus VP7 sequences, with the G type determined, based on the sequence homology. Using this assay, we have correctly identified human VP7 strains from a panel of available serotypes, as well as numerous animal strains. The assay was qualified using rotavirus positive stool samples, negative stool samples, and rotavirus-spiked stool samples. In addition, samples from cases of acute gastroenteritis collected at Children's Hospital of Philadelphia have been evaluated and indicate that the assay is able to discriminate subtle differences within serotypes. The assay has been utilized in the testing of >3,000 antigen-positive (enzyme immunoassay) samples collected during clinical trials of a rotavirus vaccine (RotaTeq) and identified a serotype in approximately 92% of samples (3, 17, 19).

Amino Acid Sequence↗
PubMed2005

Comparative typing of Campylobacter jejuni by heat-stable serotyping and PCR-based restriction fragment length polymorphism analysis.

Campylobacter jejuni has become the most common bacterial cause of human gastroenteritis worldwide. Rapid, discriminatory typing methods are required to identify potential clusters of infections. The major disadvantage of the well-evaluated and widely used Penner heat-stable serotyping method is the high level of nontypeability. The correlation of the types determined by the Penner heat-stable serotyping method and PCR-based restriction fragment length polymorphism (RFLP) analysis of the lipooligosaccharide (LOS) biosynthesis genes of C. jejuni was studied with 149 C. jejuni strains. Of these strains, 79 were patient strains belonging to 25 Penner serotypes, 60 were nontypeable patient strains, and 10 were reference strains. A 9.6-kb DNA fragment of the LOS gene cluster was amplified and digested with the restriction enzymes HhaI and DdeI. Altogether, 39 different RFLP types (including 30 HhaI profiles and 32 DdeI profiles) were identified. Type Hh1Dd1 was the most common type, with 36% of the strains and strains of 12 serotypes being of this type. A high level of discrimination was obtained, and a correlation between the Penner serotypes and the PCR-RFLP types could be seen. Also, variation in the LOS biosynthesis genes within a single Penner serotype was found. Although the PCR-RFLP method may not be sufficient to compensate for Penner serotyping, it can give valuable information about nontypeable strains and further characterize strains of common serotypes.

Bacterial Typing Techniques↗
PubMed2006

Identification of invasive serotype 1 pneumococcal isolates that express nonhemolytic pneumolysin.

Recently, there has been an increase in invasive pneumococcal disease (IPD) caused by serotype 1 Streptococcus pneumoniae throughout Europe. Serotype 1 IPD is associated with bacteremia and pneumonia in Europe and North America, especially in neonates, and is ranked among the top five most prevalent pneumococcal serotypes in at least 10 countries. The currently licensed pediatric pneumococcal vaccine does not afford protection to this serotype. Upon screening of 252 clinical isolates of S. pneumoniae, we discovered mutations in the pneumolysin gene of two out of the four serotype 1 strains present in the study group. Analysis of an additional 28 serotype 1 isolates from patients with IPD from various Scottish Health Boards, revealed that >50% had mutations in their pneumolysin genes. This resulted in the expression of nonhemolytic forms of pneumolysin. All of the strains producing nonhemolytic pneumolysin were sequence type 306 (ST306), whereas those producing "wild-type" pneumolysin were ST227. The mutations were in a region of pneumolysin involved in pore formation. These mutations can be made in vitro to give the nonhemolytic phenotype. Pneumolysin is generally conserved throughout all serotypes of S. pneumoniae and is essential for full invasive disease; however, it appears that serotype 1 ST306 does not require hemolytically active pneumolysin to cause IPD.

Animals↗
PubMed2006

Validation of a multiplex pneumococcal serotyping assay with clinical samples.

We have recently developed a rapid pneumococcal serotyping method called "multibead assay" (J. Yu et al., J. Clin. Microbiol. 43:156-162, 2005) based on a multiplexed immunoassay for capsular polysaccharides in lysates of pneumococcal cultures. The multibead assay can identify 36 serotypes (1, 2, 3, 4, 5, 6A, 6B, 7A/7F, 8, 9L/9N, 9V, 10A/10B/39/33C, 11A/11D/11F, 12A/12B/12F, 14, 15B/5C, 17F, 18C, 19A, 19F, 20, 22A/22F, 23F, and 33A/33F). More than 90% of the U.S. isolates express one of these serotypes (J. B. Robbins et al., J. Infect. Dis. 148:1136-1159, 1983). To validate the new assay, we examined 495 clinical isolates of pneumococci obtained in Brazil, Denmark, and Mexico. Pneumococci were serotyped by the Neufeld test in their countries of origin, and lysates of each strain were coded and mailed to the United States for the multibead assay at ambient temperature without any thermal protection. After breaking the code, 54 discrepancies (11% of samples) were noted, but 46 were due to nonreproducible technical problems or insufficient growth of the pneumococci. All of the isolates grew well for a second test, and therefore, the culture medium used for the multibead assay is adequate. The discrepancies persisted for eight isolates, involving the 6A, 11A, and 18C serotypes. Additional studies of the eight isolates showed that the discrepancies were due to differences in the reagents used in the multibead or Neufeld tests for these three serotypes. For instance, five isolates were typed as 6A with the Neufeld test but as nontypeable by the multibead assay. Selection of another new monoclonal antibody (Hyp6AG1) for the multibead assay resulted in all five discrepant isolates typing as 6A. This finding indicates the validity of the multibead assay and emphasizes the need to validate any new pneumococcal serotyping assay with a large number of clinical isolates from different locations. It also suggests the presence of serological subtypes among isolates expressing the 6A serotype.

Bacterial Capsules↗
PubMed2002

Cross-packaging of a single adeno-associated virus (AAV) type 2 vector genome into multiple AAV serotypes enables transduction with broad specificity.

The serotypes of adeno-associated virus (AAV) have the potential to become important resources for clinical gene therapy. In an effort to compare the role of serotype-specific virion shells on vector transduction, we cloned each of the serotype capsid coding domains into a common vector backbone containing AAV type 2 replication genes. This strategy allowed the packaging of AAV2 inverted terminal repeat vectors into each serotype-specific virions. Each of these helper plasmids (pXR1 through pXR5) efficiently replicated the transgene DNA and expressed helper proteins at nearly equivalent levels. In this study, we observed a correlation between the amount of transgene replication and packaging efficiency. The physical titer of these hybrid vectors ranged between 1.3 x 10(11) and 9.8 x 10(12)/ml (types 1 and 2, respectively). Of the five serotype vectors, only types 2 and 3 were efficiently purified by heparin-Sepharose column chromatography, illustrating the high degree of similarity between these virions. We analyzed vector transduction in reference and mutant Chinese hamster ovary cells deficient in heparan sulfate proteoglycan and saw a correlation between transduction and heparan sulfate binding data. In this analysis, types 1 and 5 were most consistent in transduction efficiency across all cell lines tested. In vivo each serotype was ranked after comparison of transgene levels by using different routes of injection and strains of rodents. Overall, in this analysis, type 1 was superior for efficient transduction of liver and muscle, followed in order by types 5, 3, 2, and 4. Surprisingly, this order changed when vector was introduced into rat retina. Types 5 and 4 were most efficient, followed by type 1. These data established a hierarchy for efficient serotype-specific vector transduction depending on the target tissue. These data also strongly support the need for extending these analyses to additional animal models and human tissue. The development of these helper plasmids should facilitate direct comparisons of serotypes, as well as begin the standardization of production for further clinical development.

Amino Acid Sequence↗
PubMed2004

Evaluation of Pasteurella multocida isolated from rabbits by capsular typing, somatic serotyping, and restriction endonuclease analysis.

The goal of this study was to characterize Pasteurella multocida isolated from rabbits. Five hundred and fifty-three apparently healthy rabbits were sampled for this study. Nasal swabs were collected from each rabbit for P. multocida isolation and identification. Isolates were further characterized by capsular and somatic antigens and genomic DNA fingerprinting. Thirty-nine P. multocida isolates were recovered from 553 rabbits (7%). Capsular typing was done by depolymerization of P. multocida capsule by Staphylococcus aureus hyaluronidase and by disc diffusion with mucopolysaccharidase enzymes (heparinase III, chondroitinase AC, and hyaluronidase). Thirty-one (79%) of the isolates were capsular type A, and 8 isolates (21%) had untypable (UT) capsules. The gel-diffusion precipitin test was used to determine the somatic type of P. multocida isolates. Nineteen isolates were somatic serotype 3 (49%), 12 were serotype 1 (31%), 1 was serotype 2, 2 were serotype 5, 2 were serotype 12 with a weak reaction to antiserum raised against serotype 7 (5%), and 1 was serotype 4. Two of the isolates (5%) were UT. Restriction endonuclease analysis of the DNA of the isolates revealed 7 distinct profiles by digestion with HindIII, and 12 profiles were obtained with HpaII, whereas digestion with EcoRI did not differentiate between any of the P. multocida DNA isolates studied. The DNA restriction endonuclease enzyme HpaII was found more useful for differentiating between DNA fingerprints of P. multocida rabbit isolates. However, no correlation between capsular type, somatic serotypes, and DNA fingerprints was seen in this study.

Animals↗
PubMed2002

Limitations of Pneumovax as a detection antigen in the measurement of serotype-specific antibodies by enzyme-linked immunosorbent assay.

BACKGROUND: Measurement of antibody responses to polysaccharide antigens is regarded as an important assessment of an individual's ability to respond to carbohydrate antigens. The currently used assays for the measurement of pneumococcal-specific antibody use the multi-serotype vaccine Pneumovax as the detection antigen. METHODS: An equal potency enzyme-linked immunosorbent assay (ELISA) system was used to compare the measurement of serotype-specific antibody with the multi-serotype assay. RESULTS: Our results show that the concentration of specific antibody to Pneumovax is not related to the concentration of antibody to the individual serotypes. Neither is any correlation found between the antibody concentrations to any of the three single serotypes investigated, to the mixture of the three serotypes or to Pneumovax. CONCLUSION: We conclude that the measurement of the concentration of the specific antibody to the mixed serotypes present in Pneumovax has serious limitations when used to evaluate the protection acquired from Pneumovax immunization against any specific serotype.

Antibodies, Bacterial↗
PubMed1992

Identification of the cross-reacting antigen among Actinobacillus pleuropneumoniae strains of serotype 1, 9 and 11 by use of monoclonal antibodies.

Two monoclonal antibodies (MAbs), lMAb-1 and lMAb-5, against Actinobacillus pleuropneumoniae serotype 1 were obtained. In enzyme-linked immunosorbent assay-inhibition tests with whole cell antigens obtained from serotype 1 to 12 strains of A. pleuropneumoniae, lMAb-1 reacted to only a serotype 1, strain 4074. The epitope recognized by lMAb-1 was a carbohydrate sensitive to periodate oxidation and resided on capsular polysaccharide (CP) of A. pleuropneumoniae serotype 1. On the other hand, lMAb-5 reacted with serotype 1, 9 and 11 strains at the same degree and its epitope was found to be located on O-polysaccharide of serotype 1, 9 or 11 lipopolysaccharide (LPS). These results showed that CP was one of the serotype-specific antigens of A. pleuropneumoniae, and that O-polysaccharide of LPS obtained from serotype 1, 9 or 11 strain was the cross-reacting antigen among these strains.

Actinobacillus pleuropneumoniae↗
PubMed2004

Serotypes of Haemophilus influenzae strains isolated from pediatric patients with respiratory tract infections.

Capsular serotypes of 122 respiratory Haemophilus influenzae strains were identified utilizing antigenic examinations (Slide Agglutination Test [SAT] and counter immuno-electrophoresis [CIE]), and PCR method. Results of the two methods were compared to find disagreement. Clinical and bacteriological characteristics of encapsulated strains were analyzed. By utilizing PCR assay, 3 (2.5%) serotype b, 1 (0.8%) serotype f and 118 (96.7%) non-typeable strains were found among 122 tested strains. Discrepancy between the results of antigenic examinations and PCR assay was found in one strain. That strain gave positive results by antigenic tests with capsular type c antiserum but it was determined to be capsular type f by PCR. No serotype b- strain was detected. All the encapsulated strains displayed biotype I. All the serotype b strains produced beta-lactamase, but none of those was sulbactam/ampicillin and amoxicillin/clavulanic acid resistant. The serotype f strain was beta-lactamase non-producing ampicillin susceptible. The patients suffered from respiratory infections due to encapsulated strains displayed safe clinical manifestations and good clinical responses to antibiotic treatments using beta-lactams. In pre-vaccination era, PCR is considered to be a useful method for determination of serotypes of respiratory H. influenzae, which may contribute to reducing a possibility of clonal transmission of serotype b strains among children community, which is one of the potential risk factors for pediatric invasive infections.

Adolescent↗
PubMed1989

Actinobacillus actinomycetemcomitans serotypes and leukotoxicity in Korean localized juvenile periodontitis.

Actinobacillus actinomycetemcomitans is though to play an important role in the pathogenesis of localized juvenile periodontitis (LJP). Preliminary data suggested that the serotype distribution of A. actinomycetemcomitans in Korea and the United States differ. This study evaluated A. actinomycetemcomitans prevalence, serotype distribution, and leukotoxicity in Korean LJP patients by culture, enzyme-linked immunosorbent assay, indirect immunofluorescence, and lactate dehydrogenase release from polymorphonuclear leukocytes exposed to A. actinomycetemcomitans. A. actinomycetemcomitans occurred in 75% of LJP lesions and 6% of normal sites with approximately equal distribution of serotype a, b, and c. Single serotypes were isolated from nine patients while three patients harbored two serotypes either in the same or different disease sites. A. actinomycetemcomitans leukotoxicity occurred in 22% isolates with a 69% prevalence. Individual sites harbored both leukotoxic and non-leukotoxic strains with no serotype association. The distribution of serotypes and leukotoxic strains of A. actinomycetemcomitans in Korean LJP patients differed from those reported in the United States. This suggests that serotype b may not be more important in the pathogenesis of LJP.

Actinobacillus↗
PubMed2004

[Serotypes and antimicrobial susceptibility of Streptococcus agalactiae].

BACKGROUND: Streptococcus agalactiae or group B streptococcus, GBS, is the leading cause of neonatal and maternal infections and an opportunistic pathogen in adults with underlying disease. In the last decade, a dramatic increase in the resistance of this microorganism to erythromycin and clindamycin has been observed. AIM: To determine the serotype distribution and antimicrobial susceptibility of isolates of S. agalactiae collected from infections and colonization and to assess the genetic mechanisms of macrolide and clindamycin resistance. MATERIAL AND METHODS: A total of 100 GBS isolates were collected between 1998 and 2002, in Santiago, Chile. They were isolated from the amniotic fluid from patients with premature rupture of membranes (7 isolates), blood from neonatal sepsis (10 isolates), neonate colonizations (2 strains), skin and soft tissue infections (7 isolates), urinary tract infections (5 isolates), genital infections (3 isolates), articular fluid (one isolate), and 65 strains were recovered from vaginal colonization55. RESULTS: Serotypes Ia, II and III were the predominant serotypes identified in our study, accounting for 90 (90%) of the strains. Five isolates belonged to serotypes Ib (5%) and two (2%) to serotype V respectively; no strains belonging to serotype IV were found. All strains were susceptible to penicillin G, ampicillin and cefotaxime, and four isolates (4%) were resistant to both erythromycin (MIC >64 microg/ml) and clindamycin (MIC >64 microg/ml). The strains had a constitutive macrolide-lincosamide-streptogramin (cMLSB) resistance phenotype and the erm(A) gene was present in the four isolates. CONCLUSIONS: Serotypes Ia, II and III were the predominant serotypes in this study. All strains were susceptible to penicillin G, ampicillin and cefotaxime, and four (4%) strains were resistant to both erythromycin and clindamycin. The cMLSB resistance phenotype, and the erm(A) gene was detected in resistant strains.

Adult↗
PubMed1991

Isolation of Northway serotype and other Bunyamwera serogroup bunyaviruses from California and Oregon mosquitoes, 1969-1985.

Eight previously untyped Bunyamwera serogroup bunyaviruses that had been isolated from mosquitoes collected in California and Oregon between 1969 and 1985, were identified by cross-neutralization tests. Four viruses from Anopheles freeborni and a virus from Aedes sierrensis collected in Butte County in the Central Valley of California in 1970-71 were shown to belong to the Northway serotype. The existence of a Northway serotype virus in California had been inferred from previous serologic surveys of deer and horses, but these are the first Northway serotype viruses to be identified from the contiguous United States or from An. freeborni. This is also the first isolation of any virus from Ae. sierrensis. Two viruses from Culiseta inornata collected in Umatilla County, Oregon in 1969 may represent a new serotype in the Bunyamwera serocomplex of the Bunyamwera serogroup. The name "Stanfield" is proposed for this serotype, which is closely related to the Cache Valley and Northway bunyavirus serotypes. A virus from Ae. taeniorhynchus collected in San Diego County, California in 1985 was confirmed to belong to the Main Drain serotype. Previously, Main Drain serotype viruses in California have been associated principally with Culicoides variipennis.

Aedes↗
PubMed2026

The impact of the COVID-19 pandemic on the incidence of invasive pneumococcal disease in the Czech Republic and whole genome sequencing analysis of Streptococcus pneumoniae serotypes 3 and 19A from 2018-2024.

AIM: To describe in detail changes in the incidence of invasive pneumococcal disease in the Czech Republic during and after the COVID-19 pandemic. Another objective is molecular analysis of S. pneumoniae isolates of serotypes 3 and 19A recovered in the Czech Republic between 2018 and 2024. MATERIAL AND METHODS: Data on the incidence of invasive pneumococcal disease and S. pneumoniae serotypes were obtained from the invasive pneumococcal disease surveillance program in the Czech Republic. S. pneumoniae isolates of serotypes 3 (63) and 19A (66) from 2018-2024 were subjected to whole genome sequencing (WGS) to characterize the GPSCs (Global Pneumococcal Sequence Clusters) and STs (sequence types) and place them in a&#xa0;global context. RESULTS: Results: During the COVID-19 pandemic, a&#xa0;significant decline was observed in the incidence of invasive pneumococcal disease in the Czech Republic. Following the pandemic, the incidence of invasive pneumococcal disease rose again to significantly higher levels than before the pandemic. Compared to the 2018&#x2013;2019 period, the incidence of certain serotypes increased in 2023&#x2013;2024, including vaccine serotypes 3, 4, 14, and 15B, while the incidence of serotypes 8, 12F, and 15A, among others, decreased. Whole genome sequencing analysis demonstrated the dominance of GPSC12 ST-180 among serotype 3 isolates throughout the study period. Among serotype 19A isolates, GPSC4 prevailed, particularly ST-416. CONCLUSIONS: The COVID-19 pandemic has demonstrated how rapidly the epidemiological situation of invasive pneumococcal disease can change and that continuous, systematic surveillance of invasive pneumococcal disease is necessary. The best prevention against invasive pneumococcal disease is vaccination, primarily with higher valency pneumococcal conjugate vaccines.

Czech Republic↗
PubMed1994

In vitro and in vivo changes of serotype in Pseudomonas aeruginosa isolates by anti-pseudomonal drugs.

The present study was designed to clarify whether anti-pseudomonal drugs affected in vitro and in vivo changes in serotypes of Pseudomonas aeruginosa isolates. Forty-two isolates of P. aeruginosa belonging to different serotype groups were each incubated in Mueller-Hinton broth including piperacillin, cefsulodin, ceftazidime, imipenem, gentamicin or norfloxacin at 1 approximately 4 MICs at 35 degrees C for 20 hours. The bacterial cells in the media were serotyped after the incubation. In each experiment with these six drugs, serotypes of 4 (9.5%) to 8 (19.0%) of the 42 isolates changed to other different groups. There was no relationship between the serotypes of the variants formed with the anti-pseudomonal drugs and kinds of the drugs. In the case of P. aeruginosa TA-2 isolate, the different concentrations (1/2 MIC and 2 x MIC) of cefsulodin induced the distinct changes in serotypes such as the poly-agglutinable (M, G) and non-typable groups, respectively. The time course for the formation of the variant cells was investigated during the incubation of P. aeruginosa TA-2 isolate in the presence of cefsulodin, respectively. In this case, the variant cells appeared 6 hours after incubation and continued to grow together with the intact cells. On the other hand, the variant cells with anti-pseudomonal drugs (cefsulodin, imipenem and gentamicin) were also formed in the model infections in mice. The present results indicated that the co-existence of colonies with different serotypes in some isolates of P. aeruginosa was partially due to the alternation of serotypes with anti-pseudomonal drugs given to patients with infection.

Animals↗