A limited controlled comparative study for the evaluation of the epidemiological efficacy of live recombinant and inactivated virion vaccines from A/Philippines/2/82-like strains of influenza A (H3N2) virus was carried out in schoolchildren of 8 to 15 years of age. During the influenza epidemic of 1987-1988 caused by influenza A/Sichuan/2/87 (H3N2)-like strains and by influenza B virus in 8.2-17% of cases, a statistically significant efficacy index for live influenza vaccine was 1.8 for the laboratory confirmed A (H3N2) cases. In the group vaccinated with the inactivated vaccine the number of serologically diagnosed A (H3N2) cases was 1.6 times lower than in the group receiving placebo, this difference being statistically significant. Thus, under the conditions of significant difference in the antigenic structure of the vaccine and epidemic A (H3N2) strains, both vaccines produced some diminished but statistically significant preventive effect in vaccinated children although its level was below the optimal. Revaccination of some children with a live influenza vaccine from a new A/Sichuan/2/87-like variant of A (H3N2) virus in the autumn of 1988 with reisolation of the vaccine strain also revealed the presence of some, though weak, resistance to this strain in the children vaccinated with both vaccines.
The occurrence of Branhamella catarrhalis in the nasopharynx and middle ear exudate was investigated in 3 studies. Bacteria were isolated from the nasopharynx in 63% of 180 healthy children and B. catarrhalis, the most common bacterium present, was isolated in 36%. In 75 children with primary acute otitis media, bacteria were isolated from the nasopharynx in 98% and from the middle ear exudate in 80%. B. catarrhalis was found in the nasopharynx in 43% and in the middle ear exudate in pure culture in 9%. In those children in whom B. catarrhalis was isolated from the middle ear exudate it was also present in the nasopharynx. In 420 children, 338 with primary acute otitis media and 82 who relapsed or did not respond to previous antibiotic therapy, B. catarrhalis was isolated from the nasopharynx in approximately 50%. About half of the B. catarrhalis strains were beta-lactamase-producing and the majority of these strains were isolated in children under 3 years of age. Of children with primary acute otitis media who had beta-lactamase-producing B. catarrhalis about 50% had not previously received antibiotic treatment. B. catarrhalis is commonly found in the nasopharynx of healthy children as well as in children with acute otitis media. Many of the strains are beta-lactamase-producing though many of the children have not been previously treated with antibiotics. In middle ear exudate, B. catarrhalis is found in about 10% of cases.(ABSTRACT TRUNCATED AT 250 WORDS)
Streptococcus pneumoniae is a well-known cause of community-acquired bacterial pneumonia. The purpose of this study was to assess the cause and extent of the outbreak of pneumonia which occurred among military recruits following a 1-week hard encampment in Finland. We also assessed the carriage rate and molecular characteristics of the S. pneumoniae isolates. All pneumococcal isolates were studied for antibiotic susceptibility, serotyped, genotyped by multilocus sequence typing (MLST), and the presence of pneumococcal rlrA pilus islet was detected. The genotype results defined by MLST corresponded with the serotype results. S. pneumoniae serotype 7F, ST2331, seemed to be associated with an outbreak of pneumonia and nasopharyngeal carriage among 43 military recruits. Of the 43 military recruits, five (12%) were hospitalized with pneumonia and two (40%) of them were positive for S. pneumoniae serotype 7F, ST2331 by blood culture. Eighteen (42%) of the 43 men were found to be positive for S. pneumoniae by nasopharyngeal culture, and nine (50%) of them carried pneumococcal serotype 7F, ST2331. The outbreak strain covered 55% of all the pneumococcal findings. Outbreaks of invasive pneumococcal disease seem to occur in a crowded environment such as a military training facility even among previously healthy young men.
The objectives were to study serotypes and antibiotic susceptibility of Streptococcus pneumoniae carried by healthy children attending a day-care centre in St. Petersburg. S. pneumoniae colonization was investigated in 125 children aged 16-70 months. Antibiotic susceptibility was determined by E-test and disk diffusion. 83 S. pneumoniae cases were isolated in 75/125 (60%) children: 36/75 (48%) in the nasopharynx, 12/75 (16%) in the oropharynx and 27/75 (36%) in both. Carriage rates were 100%, 68%, 72%, 46% and 54% in children aged 12-23, 24-35, 36-47, 48-59 and >or=60 months, respectively. 97.6% of isolates were susceptible to penicillin. 61.4%, 32.5%, 19.3%, 16.7% and 6% isolates were non-susceptible to trimethoprim/sulfamethoxazole, tetracycline, clindamycin, erythromycin and chloramphenicol, respectively. 20.5% of isolates were multidrug resistant (MDR). 45% of isolates were of serotypes included in the 7-valent pneumococcal conjugate vaccine (7V-PCV); 64.9%, 56.8%, 32.4% and 27% of 7V-PCV serotypes were resistant to trimethoprim/sulfamethoxazole, tetracycline, clindamycin and erythromycin, respectively. The respective figures for MDR isolates were 100%, 94.1%, 70.6% and 76.5%; 76.5% of all MDR isolates were covered by 7V-PCV.
1) resistance to trimethoprim/sulfamethoxazole and tetracycline was high; 2) resistance to macrolides was higher than in other Russian regions; 3) 7V-PCV coverage was modest, but the vaccine may potentially reduce MDR-S. pneumoniae.
This study assessed the antimicrobial resistance of nasopharyngeal pneumococci isolated from children aged or = 4 mg/L) isolates were tested for resistance mechanisms and clonal relatedness. Non-susceptibility rates, by CLSI criteria, were 19.3%, 0.9% and 0.4% for penicillin G, cefotaxime and amoxycillin-clavulanate, respectively. Resistance to macrolides and lincosamides was also relatively low, i.e., or = 8 mg/L) were found, but 1.7% of isolates were non-susceptible (MIC 4 mg/L). No resistance was found to levofloxacin, gemifloxacin, telithromycin or vancomycin. Pulsed-field gel electrophoresis analysis showed no relationship between ciprofloxacin- and macrolide-non-susceptible isolates in European and Asian Russia. Resistance among macrolide-resistant isolates resulted mostly from the presence of erm(B) and mef(A), and from changes in L4; additionally, L22 mutations were common in isolates from Asian Russia. Non-susceptibility to quinolones was associated with mutations in parC and parE among European isolates. Asian Russian isolates had mutations in parC and gyrA, and alterations in parE were more common. There were substantial differences in non-susceptibility and mechanisms of resistance between pneumococci from Asian and European Russia, with orphanages appearing to be 'hot-spots' of resistance.
This study was performed on cases admitted to Sami Ulus Pediatric Health and Diseases Training and Research Hospital because of cough lasting two weeks or more between November, 2001 and April, 2003. According to pertussis case definitions, patient's information of each 66 probable cases complied with clinical criteria from 0-15 age group were recorded on questionnaire and nasopharyngeal samples were taken. Specimens were sent to Refik Saydam National Hygiene Centre, Pertussis Reference Laboratory in order to perform specific culture, direct fluorescent antibody (DFA) and polymerase chain reaction (PCR). Bordetella pertussis was isolated on cultures of two cases (3%) and the same specimens were found positive by DFA. Direct PCR results of nasopharyngeal samples were not evaluated since false positive reactions were obtained with one or more negative controls in different series. Since a symptomatic contact of any culture proven case is also defined as confirmed case by the standard case definitions, three of 66 cases (4.5%) together with a symptomatic contact of one of the culture positives were classified as confirmed pertussis in this study.
To study results from bacteriological specimens from nasopharynx in patients with a clinical diagnosis of acute sinusitis in relation to CT findings.
Patients from general practice in Vestfold county, Norway.
427 patients 15 years and older from two studies with a clinical diagnosis of acute sinusitis, and who were examined with coronal CT scans of the paranasal sinuses. Fluid level or total opacification of any sinus was taken as a hallmark of sinusitis.
Bacteriological findings in nasopharynx specimens and proportions of various sinus pathogens in patients with and without sinusitis confirmed by CT.
In the study, 252 patients had acute sinusitis and 175 patients did not. In the sinusitis groups, 27% of the patients had Streptococcus pneumonia, 12% had Staphylococcus aureus and 10% had Haemophilus influenzae in their nasopharynx specimens. Forty-five percent of the patients had normal nasal flora or no growth. The strains of Streptococcus pneumonia and Haemophilus influenzae showed high sensitivity to PcV, while the Moraxella strains were resistant to it.
Streptococcus pneumoniae and Haemophilus influenzae were the most frequent sinus pathogens found in the nasopharynx specimens, and they were significantly more frequent in the group with confirmed sinusitis. The proportion of specimens with normal nasal flora or no growth was significantly higher in the non-sinusitis group.
The clinical significance of pneumococcal biofilm formation is largely unknown. To clarify this, we tested whether the ability of pneumococcal clinical isolates to form biofilm in vitro accounts for the diverse clinical outcomes. Clinical pneumococcal isolates were cultured from the nasopharynx (n=106), middle ear effusion (n=43) and blood (n=55) of 204 children altogether. Biofilm formation, assessed by measuring optical density (OD) values in microtitre plates after crystal violet staining, did not differ between the bacteria from different sources (p=0.18), the mean OD values of the isolates being 0.119 [95% confidence interval (CI) 0.100-0.138] in the nasopharynx samples, 0.094 (95% CI 0.069-0.119) in the acute otitis media cases, 0.109 (95% CI 0.077-0.141) in the secretory otitis media cases, 0.122 (95% CI 0.084-0.160) in those with sepsis and 0.175 (95% CI 0.071-0.280) in those with other invasive infections. Serotypes 33 and 14 were the most efficient in forming biofilms, whereas serotypes 3 and 38 were poor biofilm producers. We conclude that the clinical presentation of pneumococcal disease did not differ in relation to biofilm formation in vitro, even though there was marked variation between the clinical isolates and serotypes.