Serotype

The aim of this study was to determine a relationship between vaccine potency (amount of PD 50 per dose) and fraction of clinically protected cattle following homologous challenge with infectious foot-andmouth disease (FMD) virus, and to determine the effect of method of fractionation, serotype, type of adjuvant, valency and type of virus culture on the dose-response curve. Data from 297 potency tests of FMD vaccines, comprising 4004 vaccinated cattle, performed at the FMD vaccine production facility in the Netherlands, were used for the present study. A generalised linear mixed effect model was used to analyse the results. Our study showed that the relation between FMD vaccine potency and fraction protected was also affected by the serotype and type of adjuvant. No common level of protection could be assigned to all FMD vaccines with the same amount of PD 50 per dose, this information is essential when designing a new standard FMD vaccines control.

A quantitative real-time TaqMan PCR assay for detection of human adenoviruses (HAdV) was developed using broadly reactive consensus primers and a TaqMan probe targeting a conserved region of the hexon gene. The TaqMan assay correctly identified 56 representative adenovirus prototype strains and field isolates from all six adenovirus species (A to F). Based on infectious units, the TaqMan assay was able to detect as few as 0.4 and 0.004 infectious units of adenovirus serotype 2 (AdV2) and AdV41, respectively, with results obtained in less than 90 min. Using genomic equivalents, the broadly reactive TaqMan assay was able to detect 5 copies of AdV40 (which had zero mismatches with the PCR primers and probe), 8 copies of AdV41, and 350 copies of AdV3 (which had the most mismatches [seven] of any adenovirus serotype tested). For specific detection and identification of F species serotypes AdV40 and AdV41, a second real-time PCR assay was developed using fluorescence resonance energy tran...

A PCR assay was developed for the detection of Streptococcus suis serotypes 2 and 1/2. This multiplex PCR is based on the amplification of the gene coding for 16S rRNA of S. suis and on the amplification of the cps2J gene coding for the capsule of S. suis serotypes 2 and 1/2. An internal control was constructed and added in this test to monitor the efficiency of amplification in each reaction. To evaluate the specificity of the test, 31 strains of other bacterial species related to S. suis or isolated from pigs and 42 strains of S. suis serotypes 1 and 3 to 34 were analyzed. The detection threshold of the test was 28 S. suis CFU/ml. The specificity and the sensitivity of the multiplex PCR test and the presence of an internal control allowed the analysis of biological samples without a culture step. The PCR assay was then applied to the detection of 14 S. suis serotype 1/2 strains, 88 S. suis serotype 2 strains isolated from pigs, and 25 S. suis serotype 2 strains isolated from humans. This test was also applied to analyze tonsil samples of pigs experimentally infected and carrier pigs without any symptoms.

We did a systematic search and synthesis of evidence on the incidence of invasive pneumococcal disease, symptomatic disease, and circulating Streptococcus pneumoniae serotypes in western Europe. Using data from studies published between 1992 and 2005 we calculated a weighted mean invasive pneumococcal disease and pneumococcal meningitis incidence rate per 100 000 children aged 2 years or younger within 95% confidence intervals, together with the prevalence of S pneumoniae serotypes and resistance to penicillin. Invasive pneumococcal disease incidence was 27·03 cases per 100 000 children under 2 years (95% CI 2·85–33·43). Heptavalent conjugate vaccine serotypes account for 43·18–75·32% of isolates among people aged under 18 years of age. 11% of isolates in individuals aged under 18 years were penicillin resistant. The incidence of invasive pneumococcal disease appeared consistently lower in western European countries compared with studies from the USA. Thus the use of studies of vaccine effectiveness based on the US population may lead to an overestimation of the benefits of its introduction in Europe.

Pseudomonas aeruginosa is an opportunistic pathogen responsible for morbidity and mortality in humans, animals, and plants. This bacterium has been regarded to be widely present in terrestrial and freshwater environments, but not in open ocean environments. Our purpose was to clarify its presence in open ocean, and their genotypic and physiological characteristics were compared with those of isolates from clinical, animal, and freshwater sources. Water samples were collected from freshwater, bays, and offshore environments in Japan. Sixty-two isolates, including 26 from the open ocean, were identified as P. aeruginosa by phenotypic characteristics and the BD Phoenix System. Pulsed-field gel electrophoresis (PFGE) was performed on all strains, together with 21 clinical and 8 animal strains. The results showed that open ocean strains are composed of a few genotypes, which are separated from other strains. Although some clinical isolates made a cluster, other strains tended to mix together. Different antibiotypes were observed among marine isolates that had similar PFGE and serotyping patterns. Some were multidrug-resistant. Laboratory-based microcosm study were carried out to see the responses of P. aeruginosa toward increased NaCl concentrations in deionized water (DW). Marine strains showed better survival with the increase, whereas river and clinical strains were suppressed by the increase. These findings illustrate the potential significance of open ocean as a possible reservoir of P. aeruginosa, and there may be clones unique to this environment. To our knowledge, this is the first report on the presence and characterization of P. aeruginosa in the open ocean.

To obtain basic data for future resistance monitoring programs, 386 Yersinia enterocolitica strains from human patients, raw retail pork and pig feces were tested for their susceptibilities to 16 antimicrobial agents and two antimicrobial growth promoters (carbadox and olaquindox). No strains were resistant to ceftriaxone, cefuroxime, ciprofloxacine, gentamicin, kanamycin, neomycin or polymyxin. Although in Switzerland carbadox and olaquindox were used as growth promoters for pigs for over 25 years, all strains were susceptible to them. In contrast, there were high levels of resistance to ampicillin, cefalothin and amoxicillin/clavulanic acid. Less than 10% of clinical isolates and strains from pig feces were resistant to streptomycin, sulfonamide, trimethoprim/sulfamethoxazole, tetracyclin, trimethoprim and chloramphenicol, but strains from retail pork were all susceptible to these antimicrobial agents. This finding suggested that pork is probably not a major source of Y. enterocolitica that cause human infections in Switzerland. A difference between clinical isolates and strains from pork was also shown by serotyping. Clinical isolates frequently belonged to the O3 and O9 groups whereas these two serotypes were not found in strains from pork. Resistance to multiple antimicrobial agents was rare. When examined by pulsed field gel electrophoresis (PFGE), two strains of fecal origin with an identical pattern of resistance to six antimicrobial agents were shown to be unrelated. Of four clinical isolates with resistances to five antimicrobial agents, two were of the same pulsotype. Retrospectively, it was found that these strains came from two members of the same household and thus represented a minioutbreak.

The polysaccharide capsule is a major virulence factor of Streptococcus pneumoniae; it affects complement resistance and shields the bacterium from phagocytes. Certain capsular serotypes appear to be better able to cause invasive disease than others. Serotypes 1 and 5 are common causes of invasive disease but are rarely isolated from healthy carriers, whereas serotypes 6B and 23F are more frequently isolated from carriage than invasive disease. We have recently shown that serotypes 6B and 19F differ in resistance to complement C3 deposition and opsonophagocytic killing. In this study we assessed the complement resistance and susceptibility to opsonophagocytosis of several other serotypes targeted by the pneumococcal conjugate vaccines. Clinical isolates of serotypes 1, 4, 5, 14, 18C, and 23F were tested along reference strains of corresponding capsular types. The concentration of anticapsular antibodies required for opsonophagocytic killing correlated inversely with C3 deposition on the serotype. Serotype 1 was the most resistant of the clinical isolates to C3 deposition and, along with serotypes 5 and 19F, required the highest concentration of capsule antibodies for opsonophagocytic killing, whereas serotype 23F was the most sensitive to opsonophagocytosis. Sensitivity to C3 deposition and opsonophagocytosis was associated with serotype-specific mortality of invasive pneumococcal disease, suggesting that the primary pathogens, such as serotypes 1 and 5, are more resistant to complement and require a higher concentration of capsule antibodies for opsonophagocytic killing than the opportunistic serotypes such as 6B and 23F, which are associated with a more severe disease outcome.

Toscana virus (Bunyaviridae family, Phlebovirus genus) is a sandfly fever virus responsible for human neurological infections. Sandfly viruses are transmitted by insect vectors (Phlebotomus species) and the infection is present in climatic areas that allow the life cycle of the vector. The arthropode-borne Toscana virus is the etiologic agent of meningitis, meningoencephalitis, and encephalitis. The frequency of this neuropathic infection increases in the summer months, peaking in August in the endemic Mediterranean areas (Italy, Portugal, Spain, and Cyprus). Infection diagnosis is carried out by molecular assays and immunoenzymatic tests, which are rapid and sensitive. Recent studies have investigated the antigenic properties of the viral proteins (nucleoprotein N and surface glycoproteins G1 and G2), to better understand their immunogentic role.

Background. Purpura fulminans is an acute illness commonly associated with meningococcemia or invasive streptococcal disease, and it is typically characterized by disseminated intravascular coagulation (DIC) and purpuric skin lesions. In this article, we report the first 5 cases (to our knowledge) of purpura fulminans directly associated with Staphylococcus aureus strains that produce high levels of the superantigens toxic shock syndrome toxin-1 (TSST-1), staphylococcal enterotoxin serotype B (SEB), or staphylococcal enterotoxin serotype C (SEC).

The present study was conducted to investigate, for the first time in Tunisia, the current trends in Salmonella enterica serotypes in Tunisia (human, food, animal, and environment) which would help to improve the control and prevention of Salmonella infections.

Martinique experienced a dengue outbreak with co-circulation of DENV-2 and DENV-4. In an emergency department-based study, we analyzed whether the clinical presentation and outcome of adult patients were related to serotype, immune status, or plasma viral load. Of the 146 adult patients who had confirmed dengue infection, 91 (62.3%) were classified as having classic dengue fever, 11 (7.5%) fulfilled World

A quantitative one-step SYBR Green I-based reverse transcription (RT)-PCR system was developed for the detection and differentiation of four different dengue virus serotypes in acute-phase serum samples. A set of group-and serotype-specific primer pairs was designed against conserved sequences in the core region and evaluated for clinical diagnosis. A linear relationship was obtained between the amount of input RNA and cycle threshold (Ct) value over a range of 10 to 10 7 PFU per ml of cell culture-derived dengue viruses. The detection limit of the group-specific primer pair was between 4.1 and 43.5 PFU/ml for four dengue serotypes. The detection limit of each of the serotype-specific primer pairs was calculated to be 10 PFU/ml for dengue virus serotype 1 (DEN-1), 4.6 PFU/ml for DEN-2, 4.1 PFU/ml for DEN-3, and 5 PFU/ml for DEN-4. Comparisons between the one-step SYBR Green-based RT-PCR assay and the conventional cell culture method in the clinical diagnosis of dengue virus infection from acute-phase serum samples of confirmed dengue patients were performed. The results showed that 83 and 67% of 193 acute-phase serum samples tested were positive by the one-step SYBR Green-based RT-PCR method and cell culture method, respectively. Further analysis showed that the one-step SYBR Green-based RT-PCR method could detect twice as many acute-phase serum samples with positive dengue-specific immunoglobulin M (IgM) and/or IgG antibodies than cell culture method. Our results demonstrate the potential clinical application of the one-step SYBR Green I-based RT-PCR assay for the detection and differentiation of dengue virus RNA.

This study was undertaken to estimate the antimicrobial resistance of Salmonella isolated from raw chicken. From November 2003 to April 2004 a total of 120 chicken carcasses were collected from 36 randomly selected sale points (supermarkets, traditional market, poultry slaughter house, flocks) in the urban and periurban zones of Dakar, Sénégal, and examined for the presence of Salmonella. Salmonella was isolated from 75 (62.5%) of the examined samples. Out of the 90 Salmonella isolates obtained, twenty one serotypes were identified, from which the most prevalent were S. Kentuchy 30%, S. Muenster (13.3%), S. Brancaster (8.8%), S. Enteritidis and S. Hadar (6.6%). All Salmonella isolates were tested for their susceptibility to 16 selected antimicrobial agents by the agar diffusion method. Seventy one (78.9%) isolates were resistant to one or more antimicrobials. Out of 71 resistant Salmonella isolates, 33 (46.5%) showed multiple resistance to five or more different antimicrobials. Resistance to ampicillin, trimethoprim, trimethoprim-sulphamethoxazole, tetracyclin and sulphonamides was the most frequent. We found 36 different patterns of multiresistant strains. The high level of antibiotic resistance of foodborne Salmonella isolates in the present study is an indication of indiscriminate and continuous use of subtherapeutic doses of antibiotics in animals. Furthermore, the results showed the possible significance of chicken meat as a source of multiple antimicrobial-resistant Salmonella for human infections and suggest the need for detailed epidemiological study.

The seven-valent pneumococcal conjugated polysaccharide vaccine PC7V was licensed for use among children in 2000. Since 90 serotypes of pneumococci exist, an increase in nonvaccine serotypes could occur through immune selection for capsular type switching. Eleven hundred sixty-eight invasive isolates (24 serotypes), recovered primarily from pediatric patients (855 isolates ‫؍‬ 73%) and 22 reference strains of known multilocus sequence types (STs) were subjected to macrorestriction profiling (pulsed-field gel electrophoresis [PFGE]). The correlation of 187 ST results (including 49 newly discovered STs) with the PFGE data assigned 1,042 (89.2%) study isolates to 46 defined clonal complexes or genetic lineages based on related multilocus STs (BURST). Seventeen clonal complexes were represented by 2 to 10 related allelic profiles (STs), while 33 lineages (including reference strains) consisted of single STs with 4 or fewer allelic identities to other STs found in the study. Expansion of the BURST analysis to a global analysis of all known pneumococcal STs (as of 27 November 2002) reduced the number of single ST lineages from 33 to 8, and the number of multi-ST clonal complexes was reduced from 17 to 13. In this work, we established the basic genetic structure within individual serotypes prior to PC7V use. The resultant database will be useful for detecting potential selective effects of this vaccine in postvaccine surveillance.

Background and Aim: Pigeon rearing has been gaining popularity for recent years. They are reared remarkably very close to the house of the owner. This activity, therefore, may pose potential threats for humans as well as other animals as pigeons may carry and spread different pathogens including drug-resistant bacteria. This study was conducted to explore the prevalence of Escherichia coli and Salmonella spp. as well as their antibiogram profile along with an association analysis. Materials and Methods: Forty swab samples were collected from 20 pigeons during the study. E. coli and Salmonella spp. were isolated and identified on various types of agars, including MacConkey, Eosin methylene blue, Brilliant green, and Salmonella-Shigella agar. Biochemical tests such as the carbohydrate fermentation test, the triple sugar iron agar slant reaction, the indole test, the methyl red test, the catalase test, as well as the Voges–Proskauer test were also performed. Besides, the presence of E....

We studied the epidemiology of the recently described serotype 6C of Streptococcus pneumoniae among a collection of carriage isolates recovered between 1996 and 2007 in Portugal. Of 4,064 isolates, 106 (2.6%) were of serotype 6C, 17.9% of which were multidrug resistant. The strains were genetically diverse.

Avian paramyxoviruses (APMV) are divided into nine serotypes. Newcastle disease virus (APMV-1) is the most extensively characterized, while relatively little information is available for the other APMV serotypes. In the present study, we examined the pathogenicity of two divergent strains of APMV-3, Netherlands and Wisconsin, in (i) 9-day-old embryonated chicken eggs, (ii) 1-day-old specific pathogen free (SPF) chicks and turkeys, and (iii) 2-week-old SPF chickens and turkeys. The mean death time in 9-day-old embryonated chicken eggs was 112 h for APMV-3 strain Netherlands and > 168 h for strain Wisconsin. The intracerebral pathogenicity index in 1-day-old chicks for strain Netherlands was 0.39 and for strain Wisconsin was zero. Thus, both strains are lentogenic. Both the strains replicated well in brain tissue when inoculated intracerebrally in 1-day-old SPF chicks, but without causing death. Mild respiratory disease signs were observed in 1-day-old chickens and turkeys when inoculated through oculonasal route with either strain. There were no overt signs of illness in 2-weeks-old chickens and turkeys by either strain, although all the birds seroconverted after infection. The viruses were isolated predominantly from brain, lungs, spleens, trachea, pancreas and kidney. Immunohistochemistry studies also showed the presence of large amount of viral antigens in both epithelial and sub-epithelial lining of respiratory and alimentary tracts. Our result suggests systemic spread of APMV-3 even though the viral fusion glycoprotein does not contain the canonical furin proteases cleavage site. Furthermore, there was little or no disease despite systemic viral spread and abundant viral replication in all the tissues tested.

Neuropeptide Y (NPY) is an endogenous peptide with powerful anticonvulsant properties. Its overexpression in the rat hippocampus, mediated by the local application of recombinant adeno-associated viral (rAAV) vectors carrying the human NPY gene, results in significant reduction of seizures in acute and chronic seizure models. In this study, we characterized a more efficient rAAV-NPY vector to improve cell transfection in the injected area. The changes included pseudotyping with the AAV vector serotype 1 (rAAV1), and using the strong constitutive hybrid CBA promoter, which contains a cytomegalovirus enhancer and chicken b-actin promoter sequences. We compared NPY expression and the associated anticonvulsant effects of this new vector, with those mediated by the former rAAV vector with chimeric serotype 1/2 (rAAV1/2). In addition, we investigated whether rAAV serotype 1 vector-mediated chronic NPY overexpression causes behavioural deficits that may detract from the clinical utility of this therapeutic approach. We report that rAAV-NPY serotype 1 vector has significantly improved anticonvulsant activity when compared with serotype 1/2 vector, as assessed by measuring EEG seizure activity in kainic acid treated rats. rAAV1-mediated NPY overexpression in naive rats did not result in alterations of physiological functions such as learning and memory, anxiety and locomotor activity. In addition, we did not observe glia activation, or humoral immune responses against serotype 1 vector, which could inactivate gene expression. Our findings show that rAAV1-NPY vector with the CBA promoter mediates powerful anticonvulsant effects and seems to be safe in rodents, thus it may be considered a vector of choice for possible clinical applications.

The genus Enterovirus (family Picornaviridae) contains five species with strains isolated from humans: Human enterovirus A (HEV-A), HEV-B, HEV-C, HEV-D and Poliovirus. In this study, a proposed new serotype of HEV-D was characterized. Four virus strains were isolated from sewage in Egypt and one strain from acute flaccid paralysis cases in the Democratic Republic of the Congo. The complete genome of one environmental isolate, the complete coding sequence of one clinical isolate and complete VP1 regions from the other isolates were sequenced. These isolates had 66.6-69.4 % nucleotide similarity and 74.7-76.6 % amino acid sequence similarity in the VP1 region with the closest enterovirus serotype, enterovirus 70 (EV70), suggesting that the isolates form a new enterovirus type, tentatively designated enterovirus 94 (EV94). Phylogenetic analyses including sequences of the 59 UTR, VP1 and 3D regions demonstrated that EV94 isolates formed a monophyletic group within the species HEV-D. No evidence of recombination was found between EV94 and the other HEV-D serotypes, EV68 and EV70. Further biological characterization showed that EV94 was acid stable and had a wide cell tropism in vitro. Attempts to prevent replication with protective antibodies to known enterovirus receptors (poliovirus receptor, vitronectin a v b 3 receptor and decay accelerating factor) were not successful. Seroprevalence studies in the Finnish population revealed a high prevalence of this virus over the past two decades.

This review covers the O antigens of the 46 serotypes of Shigella, but those of most Shigella flexneri are variants of one basic structure, leaving 34 Shigella distinct O antigens to review, together with their gene clusters. Several of the structures and gene clusters are reported for the first time and this is the first such group for which structures and DNA sequences have been determined for all O antigens. Shigella strains are in effect Escherichia coli with a specific mode of pathogenicity, and 18 of the 34 O antigens are also found in traditional E. coli. Three are very similar to E. coli O antigens and 13 are unique to Shigella strains. The O antigen of Shigella sonnei is quite atypical for E. coli and is thought to have transferred from Plesiomonas. The other 12 O antigens unique to Shigella strains have structures that are typical of E. coli, but there are considerably more anomalies in their gene clusters, probably reflecting recent modification of the structures. Having the complete set of structures and genes opens the way for experimental studies on the role of this diversity in pathogenicity.

High sheep population density, congenial climatic conditions for
Culicoides propagation, and susceptible sheep breeds may be contributing to the higher incidence of Bluetongue (BT) in Southern states of India. Sheep farming in this part of the country is nomadic in nature and BT  is  one  of  the  major  infectious  diseases  inflicting  huge  losses.  Andhra  Pradesh  is  one  of  the  Southern  states  with  high  sheep  population  in  India.  Although  isolation  studies  in  this 
region  were  started  in  1993,  concerted  efforts  only  began  in  2002.  More  than  50  isolates  were obtained in the last decade, and 7 Bluetongue virus (BTV) serotypes (1, 2, 9, 10, 12, 16 and 21) were isolated. Among them, BTV-10, BTV-12, and BTV-21 were reported for the first time from India and the genome analysis of these viruses revealed that BTV-10 and BTV-12 have  high  sequence  identity  with  the  modified  live  virus  (MLV)  vaccines  used  in  USA  and 
South Africa, respectively. At the same time, BTV-21 has probably originated from Southeast Asia. Furthermore, some of the BTV isolated from Europe have high sequence identity with viruses isolated from Andhra Pradesh indicating common ancestry. The analysis of different
isolates involved in outbreaks revealed that more than 1 BTV serotype is involved and that mixed  infections  with  different  serotypes  is  not  uncommon.  In  a  limited  study  conducted  during  2005-2009,  it  was  observed  that  most  of  the  sheep  seroconverted  to  more  than   
1 serotype, which further supports circulation of multiple serotypes and mixed infections in Andhra  Pradesh.  Based  on  the  virus  isolation  data,  in  this  study  it  was  observed  that  a  few  serotypes dominate for 3-4 years followed by domination of others. Continuous monitoring
of circulating serotypes is essential to understand the distribution and spread BTV in endemic areas and for devising suitable control measures.

Acute diarrheal disease is still one of the major public health problems worldwide. Rotaviruses (RV) are the most important viral etiologic agents and children under fi ve years of age are the target population. Objective: To investigate the rate of RV infection in hospitalized patients due to acute diarrhea in the cities of Ponta Grossa, Londrina and Assai -Paraná. Methods: Latex agglutination (LA); immunochromatography (ICG); polyacrylamide gel electrophoresis (PAGE) and negative staining electron microscopy (ME) tests were used to detect the virus. For the genotyping, RT-PCR and RT-PCR-ELISA were used, respectively, for NSP4 and VP4/VP7. Result: Out of 124 samples there were 69 positive stool samples for RV, for at least one of the used tests, 67 of them being RV group A (RV-A). Overall, most of the RV positive stool samples came from children under thirteen years of age. However, 12 positive cases occurred in patients aged 13 years or above, including an 81-year old patient. Conclusion: The data showed similar electropherotypes and genotypes G, P and NSP4 of the inland wild circulating strains of RV.

Aim: To examine the diversity of Escherichia coli serotypes found in the intestinal contents of infants who died of Sudden Infant Death Syndrome (SIDS) compared with that in comparison infants. Methods and Results: Over the 3-year period, 1989-1991, in South Australia and Victoria (Australia), a total of 687 E. coli isolates from 231 patients with SIDS (348 isolates), 98 infants who had died from other causes (144 isolates) and 160 healthy infants (195 isolates) were studied. The isolates from patients with SIDS were found to represent 119 different serotypes; the isolates from 'other cause' infants represent 97 different serotypes; and the isolates from healthy infants represent 117 different serotypes. The seven common serotypes isolated most frequently from infants with SIDS belonged to those associated with extra-intestinal infections in humans. Compared to healthy infants (6%), these were found in significantly higher proportions among infants who died of other causes (13%, P < 0AE05) or infants with SIDS (18AE7%, P = 0AE0002). Conclusions: Despite these sources yielding a wide variety of serotypes of E. coli, a pattern of certain potential pathotypes of E. coli being associated with SIDS is apparent. Significance and Impact of the Study: While SIDS remains one of the most important diagnoses of postneonatal death, its causes are still unexplained. If E. coli has a role in the pathogenesis of SIDS (as suggested by the pathotypes identified on the basis of serotype), further studies may reveal novel virulence factors that may clarify the role of this bacterium in SIDS.

Recently, 2 serologically and biochemically distinct subtypes-11Aa and 11Ab-were discovered among serotype 11A isolates of Streptococcus pneumoniae. Sequence comparison of the capsular polysaccharide synthesis (cps) loci of the 2 subtypes identified disruption of the wcjE gene, a putative O-acetyltransferase, as the genetic hallmark of the 11Ab phenotype. Directed disruption of wcjE in vitro in an 11Aa strain switched the strain to the 11Ab phenotype, confirming the role played by the gene in the divergence between the subtypes. Furthermore, sequences from 7 11Ab clinical strains each contained unrelated disruptive mutations in the wcjE gene, displaying an unprecedented degree of genetic heterogeneity in a pneumococcal serotype. We propose to name the 11Aa subtype as serotype 11A and the 11Ab subtype as 11E, a new serotype. Our findings also suggest that the diversity of pneumococcal capsules is much greater than was previously recognized.

A total of 88 Aeromonas isolates from distinct locations and sources (39 from extraintestinal infections, 31 from diarrhoeic, ten from non-diarrhoeic faeces, all human, and eight from fresh water) were subjected to phenospecies identification, serotyping, ribotyping and detection of some virulence markers. The strains belonged to four different phenospecies marked by 19 O serogroups and 38 ribotypes. No strong correlation between these parameters was found, and no group, as defined by the typing methods, could be characterized with a particular set of virulence markers. There was a clear association of ribotypes with the source of the strains. Cluster analysis allowed the identification of a complex of ribotypes belonging to distinct but related sources, including clinical and environmental isolates. These results suggest that ribotyping may be an epidemiological tool suitable for the study of Aeromonas infections.

Therapeutic failure of monotherapy with either a third-generation cephalosporin or a fluoroquinolone against nontyphoid salmonellae has been observed in clinical practice. Combination therapy with both agents is recommended in the literature for treating life-threatening infections. However, we know of no published case reports that indicate a therapeutic advantage of this combination therapy for nontyphoid salmonellae infections. We describe a 60-year-old man who had breakthrough bacteremia with vertebral osteomyelitis and paravertebral abscess caused by Salmonella enterica serotype Choleraesuis. This was not controlled with sequential monotherapy but was eventually cured with cefotaxime-ciprofloxacin combination therapy. The Etest showed that the strain was susceptible to cefotaxime and ciprofloxacin, but resistant to nalidixic acid. Cefotaxime and ciprofloxacin in combination may be considered as an option for difficult-to-treat salmonellosis.

Efforts to develop adenovirus vectors suitable for genetic interventions in humans have identified three major limitations of the most frequently used vector prototype, human adenovirus serotype 5 (Ad5). These limitations-widespread preexisting anti-Ad5 immunity in humans, the high rate of transduction of normal nontarget tissues, and the lack of target-specific gene delivery-justify the exploration of other Ad serotypes as vector prototypes. In this paper, we describe the development of an alternative vector platform using simian Ad serotype 24 (sAd24). We found that sAd24 virions formed unstable complexes with blood coagulation factor X and, because of that, transduced the liver and other organs at low levels when administered intravenously. The overall pattern of biodistribution of sAd24 particles was similar, however, to that of Ad5, and the intravenously injected sAd24 was cleared by Kupffer cells, leading to their depletion. We modified the virus's fiber protein to design a Her2-specific derivative of sAd24 capable of infecting target human tumor cells in vitro. In the presence of neutralizing anti-Ad5 antibodies, Her2mediated infection with targeted sAd24 compared favorably to that with the Ad5-derived vector. When used to target Her2-expressing tumors in animals, this fiber-modified vector achieved a higher level of gene transfer to metastasis-containing murine lungs than to tumor-free lungs. In aggregate, these studies provide important insights into sAd24 biology, identify its advantages and limitations as a vector prototype, and are thus essential for further development of an sAd24-based gene delivery platform.

Differences in the course of invasive meningococcal disease, in prevalence, case-to-carrier ratio, geographical pattern, age distribution and antibiotic resistance have been related to major serogroups and their serotypes. The relationships between Neisseria meningitidis serogroups and clinical manifestation, outcome and patient characteristics are assessed. All hospitalized patients in six major hospitals in central Israel with a verified meningococcal disease during 1990-1994 were included (n = 66). Their personal and clinical data and the results of bacteriological and serological tests of their blood and cerebrospinal fluid (CSF) were recorded. Meningococci were isolated from both blood and CSF, from blood alone, and from CSF alone in 60.6%, 18.2%, and 21.2% of the cases, respectively. The highest proportion of isolations were from infants < 1 year (34.8%), followed by children aged 1 to 5 years (25.8%). Serogroup B prevailed in 62.1%, while groups C and W135 accounted for 28.8% and 9.1%, respectively. Serogroup B predominated in children < 1 year, while in patients aged 5-22 years, C strains were the major pathogen (P < 0.001). Serogroup B accounted for 93% of the cases of meningitis, 58% of meningococcemia and 42% of fulminant meningococcemia, while group C strains were the major cause of fulminant meningococcemia (50%). The overall case fatality rate was 7.6%: fulminant meningococcemia 8.3%, and meningococcemia 10%. It was concluded that N. meningitidis group C continues to account for almost a third of the cases of meningococcal disease and is the major cause of fulminant meningococcemia.

Sequence analysis of segment 2 (seg-2) of three Indian bluetongue virus (BTV) isolates, Dehradun, Rahuri and Bangalore revealed 99% nucleotide identity amongst them and 96% with the reference BTV 23. Phylogenetic analysis grouped the isolates in 'nucleotype D'. The deduced amino acid (aa) sequence of the Bangalore isolate showed a high variability in a few places compared to other isolates. B-cell epitope analyses predicted an epitope that is present exclusively in the Bangalore isolate. Two-way cross serum neutralization confirmed that Bangalore isolate is antigenically different from the other two isolates. The results of this study suggest that these three isolates are VP2 variants of BTV 23. This signifies that non-crossneutralizing variants of the same BTV serotype should be included in vaccine preparation.

Background. Adenoviruses are associated with sporadic infection and community and institutional outbreaks; they can cause especially severe disease in infants, young children, immunocompromised persons, and transplant recipients. Fifty-two adenovirus serotypes have been recognized and classified within 7 subgroups or species (A-G), with limited data available on associated clinical syndromes and disease severity in more than one-half of the known serotypes. Methods. We describe the clinical presentation and virologic characterization of 1 adult and 2 pediatric patients admitted to 2 separate hospitals during April-May 2006 with severe acute respiratory tract infection. All patients had underlying chronic pulmonary disease; none were severely immunocompromised. All 3 experienced serious chronic sequelae or died. Results. Adenovirus was isolated from all 3 case patients. Adenovirus serotype 14, a subspecies B2 serotype not previously associated with severe clinical illness, was confirmed by neutralization assay and sequencing of the hexon gene. Restriction enzyme analysis with BamHI, BglII, HindIII, and SmaI showed all 3 viruses to be identical and to belong to a new genome type that we have designated "Ad14a." Conclusions. Our identification of severe respiratory illness due to a previously rarely reported adenovirus serotype may signify the emergence in the United States of a new genomic variant that has the potential to spread globally and cause epidemics. These case reports highlight the need for rapid diagnosis and improved surveillance, with serotyping and molecular characterization, to identify emerging variants of adenovirus, which may assist with targeted development of antiviral agents or type-specific vaccines. Human adenoviruses (Ads) are ubiquitous. The clinical spectrum of disease in humans can vary substantially, depending on the infecting serotype, and can include asymptomatic infection, pharyngoconjunctival fever, pneumonia, epidemic keratoconjunctivitis, acute hemorrhagic cystitis, gastroenteritis, meningoencephalitis, hepatitis, myocarditis, and life-threatening disseminated disease [1]. Ads have been associated with sporadic infection, as well as with community and institutional outbreaks. Common affected populations

This study was carried out to elucidate the epidemiological trends and antimicrobial susceptibilities against Salmonella serovars among Thai patients and asymptomatic carriers during 2001-2006 in central Thailand. A total of 1,401 human and 260 non-human isolates from various sources were included. The isolates were characterized using serotyping and antimicrobial susceptibility testing. The most common serovars in patients submitting stool samples were S. Weltevreden, S. Stanley, S. Anatum, and S. Rissen. Significantly higher odds ratios were observed in blood samples versus stool sample for S. Choleraesuis, S. Enteritidis, S. Typhimurium, and S. Typhi. Children under five years old suffered the most frequently from gastroenteritis. The patients most commonly infected with an invasive serovar were children and people from 26 to 55 years of age. Antimicrobial susceptibility data revealed that S. Schwarzengrund, S. Choleraesuis, S. Anatum, S. Stanley, S. Rissen, and S. Typhimurium we...

We evaluated a biochemical assay based on the ability to metabolise L-phenylpropionic acid (PPA) as a diagnostic aid in the identification of typical enteropathogenic Escherichia coli (EPEC) strains. A total of 1061 E. coli strains of serogroups O55, O111, and O119 were initially characterised regarding their H types (serotypes) and the presence of EPEC DNA sequences, eae, EAF, and bfpA. In case of the serogroup O111 strains, 84.6% carried the typical EPEC markers, and the great majority of those (98.1%) were PPA-positive. In contrast, only 0.9% of the serogroups O55 and O119 strains carrying the typical EPEC markers (53.6% and 75.4%, respectively) were PPA-positive. We conclude that the PPA test is a useful method to detect typical EPEC strains only among strains of the O111 serogroup. ß

A total of 182 strains of Escherichia coli (133 reference strains, 22 clinical strains, nine nonmotile strains and 18 strains derived from K-12) were characterized by HhaI restriction of the amplified flagellin gene (fliC). The amplified fliC product was a single band between 0.9 and 2.6 kbp. With the collection of reference strains which represented 48 flagellar types (H-types), a total of 62 patterns (F-types) were observed after HhaI restriction. A single F-type was associated with each of 39 H-types and more than one F-type was associated with the other nine H-types. Antigenically related H-types 12 and 45 gave a single F-type. The determination of HhaI-fliC F-types could allow deduction of all H-types and subdivision of some of these. Application of this identification system to 22 E. coli clinical isolates yielded nine F-patterns and the deduced H-types were confirmed by serotyping in all cases. Nine nonmotile strains were studied and their F-types were also identified. The proposed determination of fliC restriction patterns should be helpful for epidemiological studies. © 2000 Éditions scientifiques et médicales Elsevier SAS Escherichia coli / flagellin / fliC gene / PCR / molecular epidemiology / typing system / E. coli serotyping

In this study, we developed a simple, reliable, serotype-specific PCR method to differentiate Streptococcus pneumoniae serotypes 6A, 6B, and 6C. It was more efficient and practical than the assays currently being used to identify serotypes 6A, 6B, and 6C. Of 120 selected serogroup 6 isolates from subjects with invasive (n ‫؍‬ 101) and noninvasive (n ‫؍‬ 19) pneumococcal disease, most of which were collected after 2003 in New South Wales, 45 had been identified as 6A and 75 had been identified as 6B by the Quellung reaction. PCR analysis confirmed the results for serotype 6B isolates and identified two different subtypes. Fourteen of 45 isolates that had been identified as serotype 6A actually belonged to serotype 6C.

Bluetongue is a serious hemorrhagic disease of sheep, cattle and other ruminants causing economic losses worldwide. Recent invasion of multiple bluetongue virus serotypes (BTV) in various countries warrants immediate development of efficacious vaccine that targets more than one serotype. In the present study, the cross-protective efficacy of binary ethylenimine (BEI)-inactivated BTV-1 vaccine was evaluated in Indian native sheep against virulent heterologous BTV-23 serotype challenge. BTV-1 vaccination induced significant cell-mediated immunity (CMI) as determined by lymphoproliferative responses, and increased CD8 T cell, IL-2 and IFN-␥ responses. Both naïve and immunized sheep also showed increased CD4 T cell, IL-12 and IFN-␣ responses. Collectively, these data suggested that inactivated BTV-1 vaccine induced appreciable CMI and greatly reduced the severity of heterologous BTV-23 infection.

This study focused on changes in selected parameters of humoral and cellular immunity following vaccination of mice with unique Vibrio cholerae LPS-protein-complexed conjugates. The V. cholerae detoxified LPS (dLPS)-derived antigenic structures O-specific polysaccharide (O-SP) and de-O-acylated LPS (DeOAc-LPS) were used to prepare glycoconjugates by linking both dLPSs to glucan, the immunomodulating matrix, and then to BSA carrier. Animals were given a primary vaccination and boosted at 2-week intervals with a dose of 4.5 mg saccharide antigen. The last boost was given either subcutaneously or intraperitoneally (i.p.) to compare the boosting effect and to optimize the effective immunization route. Both conjugates (O-SP-BSA and DeOAc-LPS-BSA) induced significant levels of antigen-specific Ig isotypes, especially IgG and IgM. The i.p. booster route was more effective. A T helper 1 response was achieved only by immunization with O-SP-BSA conjugate administered i.p. Significant acceleration of phagocytic capacity and respiratory burst of neutrophils was demonstrated by both immunogenic formulations. Activation of T-and B-cell adaptive immunities was exhibited as specific changes in CD3 : CD19 and CD4 : CD8 ratios, B-cell low-affinity Fcc II and III receptor expression and induction of CD45R antigen.

This study focused on changes in selected parameters of humoral and cellular immunity following vaccination of mice with unique Vibrio cholerae LPS-protein-complexed conjugates. The V. cholerae detoxified LPS (dLPS)-derived antigenic structures O-specific polysaccharide (O-SP) and de-O-acylated LPS (DeOAc-LPS) were used to prepare glycoconjugates by linking both dLPSs to glucan, the immunomodulating matrix, and then to BSA carrier. Animals were given a primary vaccination and boosted at 2-week intervals with a dose of 4.5 mg saccharide antigen. The last boost was given either subcutaneously or intraperitoneally (i.p.) to compare the boosting effect and to optimize the effective immunization route. Both conjugates (O-SP-BSA and DeOAc-LPS-BSA) induced significant levels of antigen-specific Ig isotypes, especially IgG and IgM. The i.p. booster route was more effective. A T helper 1 response was achieved only by immunization with O-SP-BSA conjugate administered i.p. Significant acceleration of phagocytic capacity and respiratory burst of neutrophils was demonstrated by both immunogenic formulations. Activation of T-and B-cell adaptive immunities was exhibited as specific changes in CD3 : CD19 and CD4 : CD8 ratios, B-cell low-affinity Fcc II and III receptor expression and induction of CD45R antigen.

High antigenic compatibility and low toxicity is associated with xenograft transplantation of porcine tissues in immunodeficient human recipients. We hypothesized that adeno-associated viruses (AAVs) of porcine origin could be highly compatible to human tissues and thus of good efficiency and low toxicity for in vivo gene transfer. Porcine tissues were screened by PCR for the presence of AAV using primers designed to bind conserved regions and amplify variable regions of an alignment of several AAV sequences available on GenBank. We isolated new AAV capsid sequences from porcine tissues and successfully generated a recombinant AAV2/po1 vector by transfection. The AAV2/po1 vector was not cross-neutralized by antisera generated against all other commonly used AAVs (serotype 1, 2, 3, 4, 5, 7 and 8) indicating a distinct antigenic profile. Preexisting immunity to AAVpo1 could not be detected in the human sera evaluated. In mice, AAV2/po1 particles expressing b-galactosidase or green fluorescent protein demonstrated high transduction efficiency in muscle fibers and the retina after intramuscular or intraocular administration. Biodistribution experiments following systemic administration showed efficient gene transfer exclusively in muscle fibers. Novel AAVs derived from porcine tissues may contribute to the generation of new preventive or curative clinical modalities acceptable for human use.

Pneumococcal capsular polysaccharide (PPS) vaccines are less immunogenic in immunocompromised than immunocompetent individuals. However, neither the efficacy of PPS vaccines in immunocompromised individuals nor the host cellular subsets required for vaccine efficacy against pneumococcal disease have been directly investigated. In this study, we vaccinated CD4-deficient (CD4 ؊/؊), CD8-deficient (CD8 ؊/؊), and secretory immunoglobulin M-deficient (sIgM ؊/؊) mice and wild-type C57BL/6 (Wt) mice with a conjugate of PPS of serotype 3 and tetanus toxoid (PPS3-TT) and determined the antibody response and efficacy of vaccination against systemic and pulmonary challenge with serotype 3 pneumococcus in immunized and control mice. Our results showed that the isotype and predominant IgG subclass of the PPS3 response differed between immunodeficient mouse strains and between immunodeficient and Wt mice, with CD8 ؊/؊ mice having the most robust response. Vaccination protected Wt, CD4 ؊/؊ , and sIgM ؊/؊ mice from death resulting from both systemic and pulmonary challenge, whereas CD8 ؊/؊ mice were protected only from systemic and not from pulmonary challenge. Passive vaccination with PPS3-TT-induced sera from Wt, CD4 ؊/؊ , CD8 ؊/؊ , and sIgM ؊/؊ mice protected naïve Wt mice from death due to pulmonary challenge; however, CD8 ؊/؊ mice were not protected by sera from Wt or CD8 ؊/؊ mice. Our findings suggest that PPS-based vaccines can be effective in the setting of CD4 T-cell deficiency but that CD8 T cells could be required for vaccine-mediated protection against pulmonary challenge with serotype 3 pneumococcus.

The results of type-specific RT-PCR diagnostic assays on foot-andmouth disease (FMD) viruses in clinical samples were mapped onto serotypespecific dendrograms representing the degree of nucleotide sequence variation between the FMD virus isolates. This novel approach assisted the selection of suitable PCR primer sets for the diagnosis of FMD virus isolates belonging to different topotypes within each serotype. These interpretations were qualified by using a universal (FMD virus group) specific primer to confirm that FMD virus RNA had been extracted from the samples under investigation. The analyses showed that the design of primer sets for the detection of FMD virus serotypes O, A, Asia 1, SAT 1 and SAT 3 were generally satisfactory, as most virus isolates within the major virus sub-groupings were successfully detected. However, the FMD virus serotype C and SAT 2 specific primers were less efficient as certain virus subgroups were not detected. This identified the need for additional or alternative primers to improve RT-PCR procedures for more comprehensive detection of divergent virus strains within these serotypes. There were some examples where not all virus isolates from the same outbreak reacted with particular type-specific primers which suggested that either further minor refinements may be necessary in the primer design or that there were shortcomings in the RT-PCR methodology.