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R Austrian

Publications and source records attributed to R Austrian.

18 recordsLinked to original sources
PubMed1978

Emergence of multiply resistant pneumococci.

Multiple antimicrobial resistance in pneumococci was detected in Johannesburg in July, 1977, and prompted an investigation of the prevalence of resistant strains in two hospitals. Carriers of Types 6A and 19A penicillin-resistant pneumococci, resistant to antibiotic concentrations ranging between 0.12 and 4 microgram per milliliter were found in 29 per cent of 543 pediatric patients and 2 per cent of 434 hospital staff members. Multiply resistant Type 19A strains, resistant to beta-lactam antibiotics, erythromycin, clindamycin, tetracycline and chloramphenicol, were isolated from 128 carriers, and were responsible for bacteremia in four patients. Isolates from 40 other carriers were resistant to penicillin alone or to penicillin and chloramphenicol or to penicillin, chloramphenicol and tetracycline. Pneumococci can be screened for penicillin resistance with a modified Kirby--Bauer technic; the strains with zones of less than 35 mm around 6-microgram penicillin disks or less than 25 mm around 5-microgram methicillin disks should be tested for sensitivity to penicillin by measurements of minimum inhibitory concentration.

Adult↗
PubMed1978

Filamentous capsulated streptococci from the human respiratory tract: chemical and immunochemical characterization of a glycoprotein capsular antigen of provisional binary capsular type 87.

A filamentous alpha-hemolytic streptococcus of provisional capsular type 87 isolated from the human respiratory tract has been shown to be binary capsulated. One of the capsular antigens appears to be a glycoprotein; the other appears to be a polysaccharide. Transformation reactions with deoxyribonucleic acid from streptococcus type 87 and a number of noncapsulated pneumococci yielded transformed pneumococci with either a glycoprotein capsule or a polysaccharide capsule, but not with both. Capsular precipitin (quellung) reactions were observed when streptococcus type 87 was treated with homologous antiserum or with antisera to either of the two distinct capsular transformants. Each of the transformed pneumococci gave a quellung reaction with its homologous antiserum or with antiserum to streptococcus type 87, but neither reacted with antiserum to the heterologous transformant. Chemical analysis showed the glycoprotein antigen of streptococcus type 87 to contain, in addition to amino acids, glucose, galactose, glucosamine, and phosphate. The amino acid composition of the glycoprotein capsular antigens from streptococcus type 87 and of those from transformed pneumococci were similar, showing only minor differences. The glycoprotein capsular antigen from streptococcus type 87 gave two closely associated precipitin bands with homologous antiserum or antisera to transformed pneumococci with the glycoprotein capsule. That the two precipitin bands represent two unrelated proteins is precluded largely on the basis of the unlikely probability of 100% cotransformation of the genes coding for both proteins in the pneumococcal transformants that were isolated. Chemical analyses of the various fractions of the glycoprotein indicate that the two precipitin bands may represent a glycoprotein and its corresponding apoprotein.

Amino Acids↗
PubMed1978

Prospects for the prevention of bacterial meningitis with polysaccharide vaccines.

MOST SUPPURATIVE INFECTIONS OF THE MENINGES ARE CAUSED BY FIVE BACTERIAL SPECIES: Escherichia coli, Haemophilus influenzae type b, Streptococcus pneumoniae, Neisseria meningitidis, and group B streptococcus. The immune response of adults to pneumococcal capsular polysaccharides has been studied in great detail and their responses to meningococcal and H. influenzae type b capsular polysaccharides are quite similar. Immune responses of adults to E. coli and group B streptococcal antigens are disappointing. The responses of children below the age of 7 years differ both quantitatively and in duration. Early experience shows that useful antibody titres can be achieved with certain antigens but further studies are required. In order to prevent bacterial meningitis by immunization, three vaccine formulations will need to be developed. When epidemic meningococcal disease occurs in a population, the vaccine containing only components of the meningococcus would be applied to a large segment of the population to terminate the epidemic. The second vaccine would contain components of H. influenzae type b, pneumococcus, and the meningococcus and would be administered in the first year of life, and repeated at suitable intervals to maintain life-long immunity. The third vaccine, designed to prevent neonatal meningitis caused by E. coli K1 and group B streptococci, would be administered to women preferably during the third trimester of pregnancy, so that their offspring would inherit sufficient antibodies to protect them during the first 3 months of life.The vaccine against the meningococcus is a reality and has been used extensively during major epidemics, with excellent results. The two vaccines for control of endemic bacterial meningitides do not exist as yet, but the prospects are good.

Adult↗
PubMed1977

Prevention of pneumococcal infection by immunization with capsular polysaccharides of Streptococcus pneumoniae: current status of polyvalent vaccines.

Because of the continuing morbidity and mortality resulting from pneumococcal infection, a program was instituted to redevelop polyvalent vaccines consisting of capsular polysaccharides of Streptococcus pneumoniae. Vaccines containing 50 microgram each of the capsular polysaccharides of as many as 13 pneumococcal types have been shown to be safe, antigenic, and 78.5% effective in the prevention of type-specific putative pneumococcal pneumonia and of type-specific pneumococcal bacteremia in adults. In a population in which pneumococcal pneumonia predominated, the total incidence of radiologically confirmed pneumonia, irrespective of cause, was reduced by 54.3% by use of a tridecavalent vaccine. The efficacy of vaccine in the prevention of infection during the first two years of life is under investigation. The vaccine is recommended for those at high risk of pneumococcal infection or of a fatal outcome from such illness.

Adult↗
PubMed1977

The bacteriology of pneumococcal otitis media.

The bacteriologic findings of 1205 episodes of pneumococcal otitis media are analyzed. Capsular types 6, 14, 19 and 23 have been found to account for more than half the initial and subsequent infections of the middle ear. Initial infection has been shown to be related to age, and recurrent infection with pneumococci of heterologous capsular types has been found to occur most often within six months of the initial attack. Nasopharyngeal carriage of the pneumococcal types most frequently causing otitis media may occur without causing infection, may antedate infection by as long as 13 months and may persist after infection for as long as 30 months. Recurrence of infection with a given capsular type has been identified following intervening infection with one or more heterologous capsular types. Simultaneous infection of the middle ear with two pneumococcal capsular types has been observed in 1% of the infections studied. The potential, but as yet unestablished, value of prophylactic vaccination against pneumococcal otitis media is considered.

Carrier State↗
PubMed1975

Spread of Streptococcus pneumoniae in families. II. Relation of transfer of S. pneumoniae to incidence of colds and serum antibody.

Factors that affect the spread of Streptococcus pneumoniae and the antibody responses associated with colonization were studied in 64 families for periods of eight to 52 weeks. Surveillance included daily recording of respiratory symptoms and bimonthly pharyngeal cultures for identification of the pneumococcal carrier state. Rhinovirus cultures were included for a portion of the study period. Intrafamilial carriage of a single type of S. pneumoniae and simultaneous spread to more than one family member were commonmspread often occurred in association with an upper respiratory tract infection; simultaneous transmission of S. pneumoniae and a rhinovirus was documented. Preexisting, type-specific serum antibody did not prevent acquisition of homotypic S. pneumoniae but did appear to shorten the duration of pharyngeal carriage. Sera of all 11 adults had greater than 150 ng of antibody nitrogen/ml of homotypic serum antibody (measured by a radioimmunoassay) before colonization. In contrast, only one of 13 preschool children had homotypic antibody concentrations of this magnitude before colonization. A threefold or greater rise in the concentration of homotypic antibody occurred in 13 of 24 children (54%) after acquisition of S. pneumoniae; the increase in antibody concentration was associated with illness in six of the children. On the other hand, acquisition of S. pneumoniae in adults was not associated with an increase in concentration of homotypic serum antibody.

Adult↗