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Almost 1000 strains representing well above 50 different species or groups of gram-negative bacteria were examined for twitching motility. This kind of motility was mainly found in strictly aerobic cocci and rods (viz. Acinetobacter calcoaceticus, Moraxella spp., Neisseria gonorrhoeae, N. meningitidis, Pseudomonas spp., phenon 3 of Thornley that is closely related to Acinetobacter, and marine, yellow-pigmented rods), but also in the facultative Eikenella corrodens and in anaerobic strains presumptively identified as "Bacteroides corrodens" earlier. Strains of species known to possess polar fimbriae were shown to exhibit twitching motility. None of the strains of species known to possess peritrichously arranged fimbriae exhibited twitching motility.

The relative sensitivities of four commercially available kits for the demonstration of the group antigen of group A streptococcus were estimated in laboratory experiments. Two kits gave positive reactions with swabs charged with approximately 10(5) colony-forming units of group A hemolytic streptococci of five common T-types. The two other kits required inocula ten times higher. Application of the antigen detection reagents from each kit to antigen extracts prepared by extraction reagents from the other kits revealed that the differences in sensitivity were largely attributable to differences in the extraction abilities. The four kits did not differ appreciably in their ability to demonstrate group A antigen in human pus mixed with group A streptococci; the minimum inoculum detectable was approximately 10(6) colony-forming units per 0.04 ml of pus.

In 11 general practice offices, with a total of 29 general practitioners, throat swabs from 468 patients with acute pharyngotonsillitis were assayed for group A streptococci with a commercial antigen detection test kit (Culturette Brand Ten-Minute Group A Strep ID; Marion Scientific, Div. of Marion Laboratories, Inc., Kansas City, MO 64114, USA). Compared to aerobic cultures carried out in our laboratory, the sensitivity of the antigen detection test was 73%; the specificity, 98%; the positive predictive value, 96%; the negative predictive value, 84%; and the overall agreement with laboratory findings, 88%. The prevalence of group A streptococci was 42%. Tests performed by assistants were significantly less sensitive (52%) than tests carried out by the physicians themselves (77%). The sensitivity of office cultures was 83% for blood agar plates supplemented with bacitracin discs, and 77% for Streptocult. We conclude that antigen detection tests should not presently be substituted for office cultures in the diagnosis of group A streptococcal throat infections.

The incidence of pneumococcal meningitis in Danish children during 1969-1978 was estimated to be 2.1/year/100,000 children from 0 to 14 years old. Fifty-five per cent of 146 children with pneumococcal meningitis and 61% of 61 with bacteraemia were below 2 years of age. Mortality from meningitis was 13% and from bacteraemia 7%. Of the children with meningitis, 14% had sequelae at the time of discharge from the hospital. Sequelae were not seen after bacteraemia. Among 277 pneumococcal isolates from spinal fluid and blood from Danish children during 1969-1978, serotypes 14, 18C, 6A + 6B, 23F, 7F and 19F, in that order of frequency, were the most common ones, accounting for 69% of all isolates. Serotypes included in current 14-valent pneumococcal polysaccharide vaccines made of 80% of all types, when types 6A and 6B are considered together (because it has been shown that they offer cross-protection).

During 6 months a trial was run on the effect of the addition of 10 per cent sucrose to blood culture media. The standard procedure for blood culturing is to inoculate the sample into 12 individual tubes, and the trial was performed by adding 10 per cent sucrose to half of the tubes and then comparing the results obtained in the tubes with and without sucrose. The overall isolation rate of microorganisms was not affected but the detailed comparison showed that for nearly all species the sucrose containing media tended to yield growth more frequently than the media without sucrose. This difference was statistically significant for enterobacteria and Staphylococcus aureus.

A review of 1547 official hospital record summaries concerning discharges during the period 1980 through 1983 of patients whose diagnoses had been coded as acute rheumatic fever revealed that in only 61% of the cases had this illness been diagnosed or suspected. A substantial proportion of the remaining patients had had acute non-rheumatic pericarditis diagnosed. The medical records were analyzed for 141 patients diagnosed in 1980 or 1983 by hospital departments as having acute rheumatic fever with regard to the revised Jones criteria. They were fulfilled in 47 patients, 23 of whom were considered unlikely cases of rheumatic fever. Eight patients were considered possible cases, although they did not fulfill the revised Jones criteria. The current annual incidence of acute rheumatic fever was estimated to be at most 0.3 per 100000 inhabitants.

Early works leading to the detection of the pneumococcus and eventually to the appreciation that isolates differed in agglutination and that antisera differed in their capacity to protect against pneumococcal infection in the mouse protection test are reviewed. Studies by researchers from Europe, South Africa, and the United States over nearly five decades led to the introduction of serum therapy. Rapid typing methods thus became very important, and type-specific serum therapy generated a dramatic decrease in the number of deaths from pneumococcal pneumonia. Just before the introduction of sulfonamides and, shortly thereafter, penicillin, the use of horse sera was replaced by the use of rabbit sera for a number of reasons. The present methods of typing comprise the capsular reaction test, latex- and coagglutination, and capillary precipitation, to name the most important; these use a large variety of antisera. Newer methods include the use of DNA probes and DNA sequence-based subtyping.

The number of reported cases of invasive pneumococcal infections in Sweden increased more than threefold from 1988 through 1992. We studied the capsular types and the antibiotic susceptibility of 619 pneumococcal strains isolated from blood or CSF at 18 Swedish microbiological laboratories in 1987 and in 1992. These strains belonged to 35 of the 84 recognized capsular types. We noted a remarkable increase in the prevalence of invasive infections with type 14 from 1987 (8.2%) to 1992 (18%) (P = .001), which correspond to a sevenfold increase in absolute numbers. The most prominent increase in infections was seen among elderly people; in 1992, type 14 accounted for 22.5% of the isolates from infected persons who were >64 years of age. The majority of the strains were susceptible to all antibiotics tested. However, there was a significant increase in trimethoprim-sulfamethoxazole resistance from 1.4% in 1987 to 7.1% in 1992. Nine multiresistant isolates (1.5%) were found.

Countercurrent-immunoelectrophoresis (CIE) was used to detect pneumococcal capsular polysaccharide and C-polysaccharide (C-Ps) antigens in urine. The neutral capsular polysaccharides of types 7F and 14 were detected by coagglutination. We found pneumococcal polysaccharide in urine with the same frequency in two groups of patients, i.e. a non-bacteraemic pneumonia group (68%) and a group of patients with pneumococcal bacteraemia (66%). C-Ps was detected in the urine of two patients (4%) and, therefore, this test has no value in the diagnosis of pneumococcal infections. Since there is no sensitive, non-invasive, single procedure for the diagnosis of non-bacteraemic pneumococcal pneumonia we conclude that attempts to detect pneumococcal capsular polysaccharide by CIE in combination with coagglutination (types 7F and 14) may be a useful diagnostic supplement in the search for the etiological agent in pneumonia in adults until new, more sensitive diagnostic methods have been developed.

Penicillin-resistant clinical isolates of Streptococcus pneumoniae contain mosaic penicillin-binding protein (PBP) genes that encode PBPs with decreased affinity for beta-lactam antibiotics. The mosaic blocks are believed to be the result of gene transfer of homologous PBP genes from related penicillin-resistant species. We have now identified a gene homologous to the pneumococcal PBP2x gene (pbpX) in a penicillin-sensitive Streptococcus oralis isolate M3 from South Africa that diverged by almost 20% from pbpX of penicillin-sensitive pneumococci, and a central sequence block of a mosaic pbpX gene of Streptococcus mitis strain NCTC 10712. In contrast, it differed by only 2-4% of the 1 to 1.5 kb mosaic block in pbpX genes of three genetically unrelated penicillin-resistant S. pneumoniae isolates, two of them representing clones of serotype 6B and 23F, which are prevalent in Spain and are also already found in other countries. With low concentrations of cefotaxime, transformants of the sensitive S. pneumoniae R6 strain could be selected containing pbpX genes from either S. mitis NCTC 10712 or S. oralis M3, demonstrating that genetic exchange can already occur between beta-lactam-sensitive species. These data are in agreement with the assumption that PBPs as penicillin-resistance determinants have evolved by the accumulation of point mutations in genes of sensitive commensal species.

We have developed an ELISA for antibody determination, superior to others hitherto described, in which optimal coating is achieved using phenylated pneumococcal capsular polysaccharides as coating antigen. The specificity of the assay is ensured by complete inhibition of antibodies against the species-specific pneumococcal antigen, C-polysaccharide (C-Ps). The method is sensitive, specific, reproducible, fast and easy to work with and can be used for both immunoglobulin class and subclass antibody determinations.

The ability of antibodies against C-polysaccharide (C-Ps) to protect against experimental pneumococcal infection was examined in a mouse model. No protection against types 6A and 14 pneumococcal infection could be demonstrated neither with mouse monoclonal antibodies against C-Ps, specific for phosphorylcholine (PC) or for C-Ps backbone, nor for polyclonal rabbit immunsera against C-Ps. The monoclonal antibody with PC-specificity was protective against infection with type 27 pneumococcus, that has PC as part of its capsular polysaccharide. Type-specific mono- and polyclonal antibodies were highly protective against infection with the homologous type. We conclude that no species-specific protection can be achieved against intraperitoneal Streptococcus pneumoniae infection with optimally capsulated bacteria in outbred mice by passive immunization with antibodies to C-Ps.

The capsular polysaccharide elaborated by Streptococcus pneumoniae type 7B is composed of the following heptasaccharide repeating-units. [formula: see text] The identities and modes of linkage of the constituents were established using sugar, methylation, and phosphorus analysis, together with 1D- and 2D-n.m.r. spectroscopy. The sequence was established from inter-residue n.O.e. data. The structure was corroborated by n.m.r. spectroscopy, f.a.b.-m.s., and methylation analysis of the oligosaccharides isolated after partial acid hydrolysis of the polysaccharide with aqueous 48% hydrogen fluoride. It is suggested that the structural basis for the common antigenic formula in the group 7 serotypes of S. pneumoniae is the disaccharide element alpha-D-GlcpNAc-(1----2)-alpha-L-Rhap-(1----.

In a prospective study of the etiology of pneumonia 196 adult patients were included. One of the following criteria was required for diagnosis of pneumococcal pneumonia: isolation of pneumococci from blood; isolation from transtracheal aspirate; isolation from sputum or nasopharynx or detection of capsular antigen in sputum in combination with a significant increase in antibodies against at least one pneumococcal antigen (type-specific capsular polysaccharide, C-polysaccharide, pneumolysin); or increase in antibodies against two pneumococcal antigens. Pneumococcal pneumonia was diagnosed in 63 patients (32%). Other diagnoses were nonencapsulated Haemophilus influenzae isolated from transtracheal aspirates, 9; Mycoplasma pneumoniae diagnosed by serology, 17; Chlamydia psittaci, 6; and viral infections, 42. Twenty-two patients (11%) had evidence of infection with more than one agent. The pathogen could not be determined in 70 (36%). Many patients were given antibiotics before admittance to the study, and in some cases a convalescent serum sample was not available.

Summary In order to evaluate the antibody response to primary pneumococcal vaccination in the elderly, 20 healthy persons aged 60 years or older, (mean age 62.8) were vaccinated with a 23-valent pneumococcal polysaccharide vaccine (Pneumovax® 23). Blood samples were taken before and 4 weeks after vaccination and pneumococcal antibody concentrations were measured by ELISA and compared with those obtained after vaccination of younger persons (mean age 39 years). Significantly lower anti-type 2 antibody concentrations were found in the elderly after vaccination. Apart from this, no other significant differences were found neither in pre- and post-vaccination antibody concentrations nor in antibody fold increases between the two groups.

The attachment of capsular polysaccharide to Streptococcus pneumoniae was examined using monoclonal and polyclonal antibodies. Among the strains examined, the capsular polysaccharide of types 2, 4, 6A, 6B, 7F, 8, 14, 19F and 23F was bound to the pneumococci whereas that of a type 3 strain was not. Sequential treatment with 2% SDS at 100 degrees C, pronase, and EDTA did not dissociate the capsular polysaccharide from the pneumococci. Treatment of the cells with mutanolysin, a muramidase that degrades the cell wall peptidoglycan of pneumococci and other streptococci, released both the capsular and the cell wall C-polysaccharide (C-Ps). Type 6A capsular polysaccharide released from cell walls by mutanolysin treatment, was fractionated by high performance liquid chromatography and examined by immunoelectrophoresis. It was found to be bound to both the C-Ps and the peptidoglycan. The bond between the capsular polysaccharide and the peptidoglycan has not yet been identified but is probably covalent, as the two components could not be dissociated after boiling in SDS. Based on our studies with type 6A, we propose that capsular polysaccharide and C-Ps of the pneumococcus are linked to the peptidoglycan at different sites and, thereby, indirectly to each other. Studies in mice showed that the peptidoglycan enhanced the serum antibody response to C-Ps but not to type 6A polysaccharide.

Forty-three Danish splenectomized children received a single subcutaneous dose of a 14-valent pneumococcal vaccine (Pneumovax 23; Merck). Blood samples were taken before, 4 weeks after and 5 years after vaccination. Total pneumococcal antibody concentrations as well as antibodies against each of the 14 pneumococcal capsular polysaccharide antigens were measured by the enzyme-linked immunosorbent assay method. Depending on the pneumococcal antibody status 5 years after primary vaccination, the children were either revaccinated with a new 23-valent pneumococcal vaccine or scheduled for reexamination later. The antibody concentrations found 5 years after vaccination showed a strong correlation with the prevaccination antibody concentrations. Revaccination of children with low antibody concentrations 5 years after primary vaccination is safe, is without significant side effects and leads to a satisfactory antibody response.

Streptococcus suis was isolated from 11 (10 per cent) out of 107 cases of endocarditis in slaughter pigs from which bacteria of any kind were isolated. Seven of the isolates belonged to the capsular serotypes 1, 2 and 1/2. Four were non-typable owing to lack of capsule. The organism isolated most often was Erysipelothrix rhusiopathiae, which was found in 68 (64 per cent) cases.

16 splenectomized adults, all vaccinated with a 14-valent pneumococcal vaccine (Pneumovax®) 1978–79 had their pneumococcal antibody concentrations measured before and up to 10 years after vaccination. The antibody concentrations after vaccination declined to 71% in 2 years and remained at this level during the 10-year study period. Further studies are needed to see whether this applies to all vaccinated splenectomized adults.

In 1990 we reported that the number of cases with invasive infections caused by Streptococcus pyogenes, group A Streptococci (GAS), in 1989 had been three times higher than five years earlier. We ascribed this to the sudden emergence in Denmark, as in other Scandinavian countries and in the UK, of type 1 which previously had only constituted few per cent of all blood isolates of GAS but in 1989 amounted to over 50% of such isolates (2).

Udgivelsesdato: 1996-Nov Nasopharyngeal and middle-ear colonization with bacteria and viruses, including Mycoplasma pneumoniae and chlamydiae, was investigated in a survey of 54 children with acute otitis media (AOM) and 201 control children without AOM in Greenland. In total, 98% with AOM and 91% without AOM carried potentially pathogenic bacteria in the nasopharynx. Two or more potentially pathogenic species were carried by 78% with AOM and 57% without AOM. Haemophilus influenzae was found in 92% and 77%, respectively, but only Streptococcus pneumoniae was found significantly more often in the nasopharynx of children with AOM than in age-matched controls (P < .03). The two species were found in 22 of 24 ear-discharge specimens. Nine children (three with AOM) had chlamydiae in the nasopharynx, and seven of them reported rhinitis. Enteroviruses or rhinoviruses were detected in 23 nasopharyngeal specimens from 39 children with AOM, in 13 such specimens from 39 children without AOM (P = .040), and in 4 of 14 ear-discharge specimens. The potentially pathogenic load in the nasopharynx was massive, suggesting an association with the high prevalence of otitis media among children in Greenland.

The prevalence of penicillin resistance in Streptococcus pneumoniae isolated at the Prince of Wales Hospital, Hong Kong, rose from 6.6% of sputum isolates in the first quarter of 1993 to 55.8% of isolates in the second quarter of 1995. Most of the isolates were also resistant to co-trimoxazole, tetracycline, choramphenicol and erythromycin. Type 19F was the most common capsular type in 1993-1994, comprising 40.0% of typed isolates in this period. Type 23F emerged in 1995 as the predominant type, making up 62.2% of typed isolates in the first 2 quarters of 1995. A high population density and excessive community use of antibiotics are likely to be factors promoting the rapid emergence of multiply-resistant pneumococci in Hong Kong.

Splenectomized children as well as those suffering from nephrotic syndrome or recurrent asthmatic bronchitis have an increased susceptibility to systemic pneumococcal infections compared to healthy children. To determine the immunogenicity and safety of a 23-valent pneumococcal polysaccharide vaccine (PPV), 119 children (21 healthy, 26 splenectomized children, 48 with nephrotic syndrome and 24 with recurrent asthmatic bronchitis), aged 2-18 years, received one subcutaneous injection of a 23-valent PPV. Anti-capsular antibodies (Ab) to types 6B, 9V, 14, 18C, 19F and 23F were measured by ELISA before and 4 weeks after immunization. In all cases the adverse reactions were mild and transient, consisting of local pain and/or erythema or swelling in 41% and fever above 38.5 degrees C in 2% of the children. The healthy children responded well to vaccination with a mean fold increase (FI) of 2.6 in postvaccination Ab titers compared to prevaccination titers. The combined geometric mean Ab concentrations in the high-risk children were significantly lower than those of healthy children both before and after vaccination. However, the combined geometric mean FI were not significantly different between high-risk and healthy children. These results indicate that PPV is immunogenic and safe in high-risk as well as in healthy Korean children.

The serological properties of six new pneumococcal capsular types are described. A table listing all 90 pneumococcal types and their cross-reactions is included.

Sera from patients with subacute bacterial endocarditis (SBE) due to Streptococcus mutans or other oral streptococci and from normal subjects were assayed by enzyme-linked immunosorbent assay for antibodies to defined S. mutans antigens. Antibodies of IgG and IgA isotypes to Ag I/II and Ag III were greatly elevated in S. mutans-SBE sera, and the IgA antibodies in 3 sera included both polymeric and monomeric forms. Elevated IgM and IgG anti-lipoteichoic acid and IgG and IgA anti-serotype c polysaccharide antibodies were also found. The sera of 4 of 6 patients infected with other oral streptococci also displayed antibodies to S. mutans Ag I/II. Sera of 3 patients infected with Streptococcus mitis or Streptococcus orallis. but none of the s. mutans-infected cases, showed elevated antibodies to human heart sarcolemma, and all SBE sera had elevated rheumatoid factor. These results suggest that the known surface protein antigens of S. mutans are immunodominant in humans, and are not likely to be heart cross-reactive.

Knowledge about the type distribution of Streptococcus pneumoniae is fundamental to ensure an effective formulation of pneumococcal vaccine, especially with the possibility of producing a polysaccharide-protein-conjugated vaccine for the prevention of invasive disease in children. During the 6-year period 1982-1987, we received and typed 10,298 isolates from patients with invasive pneumococcal disease: 7,812 (76%) from blood and 2,486 (24%) from CSF. Of all isolates, 81% were recovered from individuals in Europe and 23% were from children. In order of frequency, S. pneumoniae types 6A + 6B, 14, 18C, 19F, 1, 7F, 23F, 19A, 4, and 5 were most commonly isolated from children, and types 3, 1, 14, 7F, 4, 6A + 6B, 8, 23F, 9V, and 19F, from adults. The pneumococcal types in the currently available 23-valent vaccine represented 87% of all isolates in this study, but the proportion of vaccine types varied somewhat with age and source. In all pneumococcal groups included in the vaccine, the vaccine types represented > 80% of the isolates, except in groups 6, 15, and 18.

The present investigation was performed in order to evaluate the use and benefit of in-the-ear hearing aids (ITE-HAs) after a 4-year observation period, and to examine the validity of this type of hearing aid. A sample of 537 subjects still in possession of ITE-HAs, fitted in 1985, responded to a postal questionnaire in 1989, including questions identical to the first follow-up in 1985. The 537 persons correspond to 60% of the originally fitted sample of 894 subjects. The investigation indicated that no change in the use of or benefit from ITE-HAs has taken place during a 4-year period, and in addition the manipulative skills of the hearing aid users did not improve. However, the overall frequency of handling problems is low, though with a tendency to increase in the age group above 75 years. It is concluded that the use of and benefit obtained with ITE-HAs remains unchanged over a 4-year period; that the use and benefit is similar in the age groups below and above 75 years of age; that the ITE-HAs seem to be fairly stable during a 4-year period.

Application of methylation analysis, specific degradations, and n.m.r. spectroscopy to the capsular polysaccharide elaborated by Streptococcus pneumoniae type 7A indicates a hexasaccharide repeating-unit with the structure (Formula; see text).

Background: A substantial proportion of patients admitted to the hospital for pneumonia have been treated in a hospital during the preceding 4 to 5 years, and patients previously treated in a hospital for pneumonia seem to be at an especially high risk for another episode of pneumonia. Many cases of pneumococcal infection might therefore be prevented by immunizing admitted patients with pneumococcal vaccine at discharge or at follow-up. The aim of this study was to investigate the type-specific antibody response to pneumococcal vaccine in middle-aged and elderly patients at follow-up 8 weeks after hospital treatment for pneumonia. Methods: A total of 92 individuals, 50 to 85 years old, participated in the study. One group consisted of 65 individuals treated in the hospital for pneumonia 8 weeks before vaccination (mean age, 67 years), and another group consisted of 27 individuals who had not recently been treated for pneumonia (mean age, 67 years). All 92 individuals received a single dose of a 23-valent pneumococcal vaccine. The type-specific antibody responses to six pneumococcal capsular polysaccharide antigens included in the vaccine as well as antibodies against the 23-valent pneumococcal vaccine were measured before and 3 to 4 weeks after vaccination by use of an enzyme-linked immunosorbent assay. Results: The antibody concentrations before and after vaccination were comparable in the two groups, as were antibody fold increases from prevaccination to postvaccination serum. No serious adverse events were recorded. Conclusions: Pneumococcal vaccination at follow-up 8 weeks after treatment in the hospital for pneumonia seems to elicit an adequate antibody response without notable adverse reactions. (Arch Intern Med. 1994;154:1961-1965)

The immunological detection of soluble pneumococcal polysaccharide antigens in pathological products is of importance in the direct diagnosis of meningitis or pulmonary infections. We have developed a double antibody sandwich ELISA method using a biotin-avidin system using antibodies constituted with a mixture of IgGs from pooled and/or monospecific antipneumococcal sera provided by the Danish Statens Seruminstitut. The sensitivity of this rapid ELISA method was optimized with purified capsular polysaccharides of the 24 main pneumococcal serotypes. With incubation steps of 30 min at 37 degrees C for the antigens and the conjugates, the detection limit was close to 1 ng/ml for 75% of the purified polysaccharides. A retrospective study of 46 CSF samples established the validity of the assay. This type of modified ELISA system represents a specific, sensitive and rapid procedure for the potential detection of capsular soluble antigens of all pneumococcal serotypes.

Group 9 organisms (types 9N, 9A, 9L, and 9V) account for about 3 to 4% of pneumococcal disease isolates throughout the world. Types 9N and 9V comprise about 90% of the group 9 disease isolates. Type 9N is more common than type 9V in adults, and type 9V predominates in infants and children. In the United States there have been eight reported cases due to group 9 pneumococci in individuals previously vaccinated; six were type 9V and two were type 9N. To ascertain the cross-immunogenicity of group 9 polysaccharides, volunteers were injected with vaccines of monovalent types 9N, 9A, 9V, or 9L, or bivalent (9N and 9A) or trivalent (9N, 9A, and 9V) polysaccharide vaccines. Monovalent types 9N, 9V, and 9L each stimulated a 5.8- to 7.5-fold geometric mean rise, and at least 80% of the volunteers responded with a twofold or greater homologous antibody rise. Type 9V induced a 5.8-fold geometric mean rise, but only 66% of the volunteers responded with a twofold or greater homologous antibody rise. Type 9N induced only a 2.1-fold geometric increase, and only 54% of the volunteers responded with a twofold or greater rise in anti 9V antibodies. Types 9L and 9A were the most cross-immunogenic. The trivalent preparation (9N, 9A, and 9V) gave the highest geometric mean titer and seroconversion rate to each of the group 9 polysaccharides. These results suggest that the polyvalent pneumococcal vaccine with its type 9N does not induce a satisfactory anti-type 9V response and should contain additional components in order to achieve greater protection against group 9 organisms.

We examined a collection of 151 strains of the viridans type of streptococci, which were isolated mainly from human oral cavities and included several reference strains, in an attempt to revise and improve the taxonomy of this group of bacteria. Our examinations included determinations of a high number of biochemical and physiological characteristics and serological reactivity. The resulting data revealed several hitherto unrecognized characters of taxonomic significance, and several of the species can now be more accurately defined. A diagnostic key to the taxa is presented. Strains previously identified as Streptococcus sanguis could be divided into two clearly distinct species, Streptococcus sanguis sensu stricto (type strain, ATCC 10556) and a new species, Streptococcus gordonii (type strain, ATCC 10558). Streptococcus mitis was divided into two biovars, consisting of strains possessing group O antigens and strains possessing group K antigen. The group of strains assigned to Streptococcus anginosus was biochemically and serologically heterogeneous, but the data did not allow natural subdivisions. Based on the results of this study, emended descriptions of the species Streptococcus oralis, S. mitis, and S. sanguis are provided. The classification resulting from this study is in complete agreement with previously published genetic data.

The structure of the capsular polysaccharide from Streptococcus pneumoniae type 2 has been reinvestigated, specific degradations and n.m.r. spectroscopy being the main methods used. It is concluded that the polysaccharide is composed of hexasaccharide repeating-units having the following structure, which differs from that previously proposed. formula; see text)

Streptococci group A, type M 1 or M 56 were capable to deplete IgG in normal rabbit sera during absorption by means of a surface Fc receptor. One absorption with 8.0 mg (dry weight) M 1 streptococci or two absorptions with 71 mg M 56 streptococci removed all IgG in 0.2 ml rabbit serum diluted 1:10 (containing 1.5 mg IgG/ml). Antibodies to egg albumin and antibodies to sheep red cells were not demonstrable after absorption of 0.2 ml serum diluted 1:10 with 16.0 mg M 1 streptococci. These results are discussed in relation to some reports on immunologic cross-reactions between streptococci and mammalian tissues.

The structure of the capsular polysaccharide elaborated by Streptococcus pneumoniae type 18F (S18F) has been investigated by using n.m.r. spectroscopy, methylation analysis, and characterisation of oligosaccharides obtained on partial hydrolysis. It is concluded that the polysaccharide is composed of pentasaccharide repeating-units having the following structure. (formula; see text) In this structure, the absolute configuration of the glycerol phosphate moiety has not been determined, but is assumed to be D-glycerol 1-phosphate (sn-glycerol 3-phosphate). The location of an O-acetyl group at O-6 of the terminal alpha-D-glucopyranosyl groups is tentative only.

Summary The Danish pneumococcal typing system, its development and its applicability are reviewed. Variations in the prevalence of pneumococcal serotypes with time and geographical area are examined. While the percentage of types in the currently available 14-valent pneumococcal polysaccharide vaccine is uniformly high in different series, typing surveillance studies must be performed, to ensure continued optimal vaccine compositions.

The effect of immunization with a 14-valent pneumococcal vaccine (Pneumovax) was studied in a double-blind trial in which 405 children between the ages of 6 months and 5 years were matched in vaccine/control pairs according to age and history of otitis media. The fact that all the children attended day-care centres ensured that both vaccinees and controls were similarly exposed to upper respiratory tract pathogens. The total incidence of acute otitis media was reduced during a 2-year follow-up period by 24% (P less than 0.05) among those vaccinated between the ages of 2 and 5. For recurrent episodes a decrease by 40% was noted. Protective efficacy was demonstrable during the first post-vaccinational year, but not when more than 1 year had lapsed after the vaccination. These findings suggest that, while the vaccine had not effect on children under 2 years old, it may be a useful aid in preventing recurrent attacks of otitis media in children between 2 and 5 years of age.

The fibrinolytic activity of human leukocytes was studied by the fibrin plate method and by the histochemical fibrin slide method, using plasminogen-rich and plasminogen-free fibrin substrates. Lysis is caused by a protease. Plasminogen activator is absent. The slide method showed the effect of leukocytes to be weak in comparison to that produced by the plasminogen activator in capillary endothelial cells invading fibrin deposits in the body.

Using an ELISA technique, changes in specific antibody levels against pneumococcal serotypes 1, 4, 7F, 14, 18C and 23F were studied in 8 adults healthy at the time of investigation but splenectomized previously because of hematological disease following infusion of 200 mg/kg body weight of a commercially available immunoglobulin preparation for intravenous use (Sandoglobulin®). Among the 4 patients with initially low serum levels of antipneumococcal antibodies, significantly raised antibody levels were demonstrated against type 14 for 8 weeks. On the other hand, the infusion did not lead to increased antibody levels in 3 patients with high preinfusion values for antipneumococcal antibodies. In contrast, a significantly lower antibody value for type 7F was recorded 3 weeks after infusion. Efficacy of immunoglobulin prophylaxis is, therefore, probably doubtful in certain splenectomized patients, and if contemplated should be preceded by analysis of antibody levels against common pathogens.

A collection of 19 strains of alpha haemolytic streptococci, isolated from throat swabs and characterized by production of spreading zones around colonies on blood agar, was found to constitute a very homogeneous group with morphological, physiological and biochemical characters corresponding to those of streptococci of ser-group H, or Streptococcus sanguis, and they all appeared to possess the group H antigen. They all had a common agglutinogen and, in addition, heterogeneous agglutinogens. The spreading growth, which appears to be a common property of S. sanguis, was due to twitching motility, and the spreading cultures possessed polar fimbriae. tneither twitching motility nor the possession of polar fimbriae have been observed in gram-positive bacteria before.

α-haemolytic streptococci, classified as Streptococcus sanguis, with spreading growth due to twitching mobility were isolated from 41 per cent of 121 swab cultures from the human pharynx. Sixty-five out of 70 isolates with spreading growth belonged to Lancefield's group H, while 5 isolates constituted a new serological entity. None of 159 non-spreading α-haemolytic streptococci isolated from the same cultures possessed either of these antigens. An examination of strains of types I, II and I/II described by Washburn et al., in the group H antisera employed in the present study indicated that type I and type I/II only differ from one another in the degree of cross-reactivity with anti-type II serum. (The type II antigen was not demonstrated in any of the isolated strains). We support the opinion that type II should not be considered as S. sanguis.

The structure of the capsular polysaccharide (S18A) elaborated by Streptococcus pneumoniae type 18A has been investigated by using methylation analysis and n.m.r. spectroscopy. It is concluded that the polysaccharide is composed of pentasaccharide repeating-units having the following structure. (formula; see text) In this structure, the absolute configuration of the glycerol 1-phosphate moiety has not been determined but is assumed to be D from biosynthesis considerations. The structure of S18A is, as expected, closely similar to those determined for S18F and S18C.

Negatively stained preparations of 30 different strains of gram-negative rods representing 20 different taxa were examined in the electron microscope. Thirteen of the strains studied exhibited twitching and six of the strains exhibited gliding motility. Additionally, non-twitching substrains of two of the twitching strains and a non-gliding substrain of one of the gliding strains were examined. A variety of cultural media, preparations for negative staining and negative stains were used. It was found that all strains with twitching motility possessed fimbriae, the diameter of which was approximately 50 A in all but one strain; the fimbriae of this strain had a diameter of approximately 40 A. The fimbriae were judged to be of polar origin in all cases where the origin could be determined with certainty. On none of the strains without twitching motility could fimbriae be demonstrated. Only one of the six strains with gliding motility possessed fimbriae.

The serologic responses to bacterial and viral antigens were determined in paired serum samples from 336 children, ages 1 month to 15 years, with roentgenographically verified community-acquired pneumonia. Significant increases in antibodies against one agent were found in 40% and against two or more agents in 8% of the children. There were significant increases in antibodies against respiratory syncytial virus in 20%, viruses of the influenza-parainfluenza group in 6% and adenovirus in 3%. A serologic response to one or more of the pneumococcal antigens used (type-specific capsular polysaccharide, C-polysaccharide and pneumolysin) was demonstrated in 13% of the patients. Ten percent of the children had significant increases in antibodies against Mycoplasma pneumoniae. Only three patients had increases against Haemophilus influenzae type b and one each against Legionella pneumophila and Chlamydia. Respiratory syncytial virus was the predominant etiologic agent in young children whereas M. pneumoniae was more frequent in the older age group.