Microbiologic analysis of results from blood cultures

The aim of our investigations was the microbiological analysis together with the evaluation of sensitivity of bacteria frequently isolated from blood cultures. Blood samples were taken from patients with symptoms suggesting bacteremia in Rydygier's Hospital in Cracow. A total of 11,170 blood samples taken from 1997 to 2000 were tested. Automatic VITAL system (bioMerieux) was applied to culture and detect microorganisms. Bacteria were identified by ATB system (bioMerieux). Susceptibility was detected by ATB and disc diffusion method. Percentage of positive results relating to detection of microorganisms of clinical significance was 16.9% (1891 cultures). Staphylococcus spp. (Staph. epidermidis in range 22.8% to 21.9%), Enterococcus spp. and Streptococcus spp. were most frequently isolated species among aerobic Gram-positive bacteria. In 2000, compared to 1997 the number of isolates of MRSA increased considerably (from 1.8% to 6.8%). In blood infections the increase of frequency of E. coli bacteria was also noted: 6.1% and 11.4% in 1997 and 2000, respectively. Among non-fermentant bacilli the percentage of occurrence of P. aeruginosa in the period of 4 years was comparable in the range 7.3% in 1997 to 7.2% in 2000. The increase in the frequency of blood infections of A. baumanii was also noticed (respectively from 4.8% to 9.9%). Susceptibility of P. aeruginosa strains to selected beta-lactame antibiotics and aminoglycosydes increased in 2000 in comparison to 1999. A. baumanii strains were 100% sensitive only to imipenem.     

Coagulase-negative staphylococci strains resistant to oxacillin isolated from neonatal blood cultures

Coagulase-negative staphylococci (CoNS) are the microorganisms most frequently isolated from clinical samples and are commonly found in neonatal blood cultures. Oxacillin is an alternative treatment of choice for CoNS infections; however, resistance to oxacillin can have a substantial impact on healthcare by adversely affecting morbidity and mortality. The objective of this study was to detect and characterise oxacillin-resistant CoNS strains in blood cultures of newborns hospitalised at the neonatal ward of the University Hospital of the Faculty of Medicine of Botucatu. One hundred CoNS strains were isolated and the mecA gene was detected in 69 of the CoNS strains, including 73.2% of Staphylococcus epidermidis strains, 85.7% of Staphylococcus haemolyticus strains, 28.6% of Staphylococcus hominis strains and 50% of Staphylococcus lugdunensis strains. Among these oxacillin-resistant CoNS strains, staphylococcal cassette chromosome mec (SCCmec) type I was identified in 24.6%, type II in 4.3%, type III in 56.5% and type IV in 14.5% of the strains. The data revealed an increase in the percentage of CoNS strains isolated from blood cultures from 1991-2009. Furthermore, a predominant SCCmec profile of the oxacillin-resistant CoNS strains isolated from neonatal intensive care units was identified with a prevalence of SCCmec types found in hospital-acquired strains.     

Proportion of fungi among isolated microorganisms from blood of patients treated in the teaching departments of The University Hospital in Cracow in 1993-1998

The study was carried out of 9742 blood cultures obtained in 1993-1998 from patients of selected departments of the University Hospital. The received samples were assessed from the standpoint of the participation of fungi strains of clinical importance as aetiological factors in systemic infections and the resistance status of a selected group of pathogens. Microbiological blood studies were conducted in the system of continuous monitoring of the obtained cultures by means of the automatic ATB system using a commercially available ID 32C set. ATB Fungus tests were used for drug resistance assessment. In all, 95 strains of yeasts (5.1%) were obtained in cultures, and an increasing variety of these pathogenic species was noted in sepsis. A systematic reduction was noted in the proportion of C. albicans and a steep rise of C. parapsilosis were observed among the aetiological factors of generalized nosocomial fungal infections. A tendency was noted for a continuous rise in the frequency of invasive candidemias with a most significant rise in their proportion in patients in general surgery and haematology departments. Among the fungi isolated from septic complications the proportion of strains resistant to antifungal drugs has been rising.     

Clinical presentation of extraintestinal infections caused by non-typhoid Salmonella serotypes among patients at the University Hospital in Cracow during an 7-year period

The most characteristic finding in non-typhoid salmonella (NTS) infection is acute food related outbreaks of gastroenteritis, which is usually benign and self-limiting. However, more serious extraintestinal findings, such as bacteraemia and focal infections localized to any organ may appear. The objective of this paper is to describe the most important characteristic of the extraintestinal infections due to NTS serotypes observed in University Hospital, in Cracow between January 2000 and December 2006. To do so, we reviewed the clinical presentations, risk groups, complications and outcomes of in-patients, in which extraintestinal non-typhoid Salmonella serotypes were isolated, applying a clinomicrobiological protocol. Out of 30 patients with either bacteraemias (n = 22) or focal salmonella infections (n = 8), 12 had malignancies, 17 had immune dysfunction state, 9 had gastrointestinal disorders and 8 had chronic heart, pulmonary or kidney disease. Four of these patients (13%) who had hematological malignancies (2), renal transplantation (1) and pulmonary disease (1) died. Regarding the clinical picture, primary bacteraemia and focal infections occurred with similar frequency (33.3% and 26.7%, respectively); the remaining were bacteraemias secondary to gastroenteritis. The incidence rate (mean 0.30/1000 hospital admission/year) increased steadily from 0.19/1000 to 0.32/1000 hospital admission during the study period. From 30 Salmonella isolates from extraintestinal samples collected, only four isolates were resistant to ampicillin, ciprofloxacin or trimethoprim-sulfamethoxazole. This finding indicate that multidrug resistance does not represent a serious problem among NTS serotypes collected from the our medical center as monitored over a period of 7 years. Given this presentation, clinicians need to have a high index of suspicion and to consider preemptive therapy, especially in elderly patients who are likely to develop severe immunosuppression following interventions.     

Profile of antifungal susceptibility of species of Candida isolated from hemocultures in a university hospital, Maracaibo, Venezuela

The aim of this study was to determine the in vitro susceptibility of amphotericin B, fluconazole and itraconazole, to several Candida spp recovered from blood cultures on hospitalized patients at the University Hospital of Maracaibo, Venezuela. The determination of the antifungal susceptibility was carried out according to the microdilution method in broth developed by The European Committee for Antimicrobial Susceptibility Testing (EUCAST). The profile of susceptibility of the 74 isolates showed that all the studied species were susceptible to amphotericin B, and 97.2% and 89.2% to fluconazole and itraconazole, respectively.     

Strict infection control measures do not prevent clonal spread of coagulase negative staphylococci colonizing central venous catheters in neutropenic hemato-oncologic patients

Coagulase negative staphylococci (CoNS) are a main cause of catheter related infections (CRI). Earlier studies (1994-1996) revealed a high incidence of CRI (6 per 1000 catheter days) among neutropenic hemato-oncologic patients in the Erasmus MC Hematology Department (Rotterdam, The Netherlands). This was mainly explained by expansion of two methicillin resistant Staphylococcus epidermidis (MRSE) clones (Nouwen et al., J. Clin. Microbiol. 36 (1998) 2696-2702). In a new, 16-bed unit in the same institution, we investigated the effect of strict clinical isolation measures on the incidence of CRI. During two 6-month screening periods (period I: April 1998-December 1998 and period II: April 1999-October 1999) all patients receiving a central venous catheter were prospectively monitored for the development of CRI. During period I every visitor of the cubicles had to wear hair caps, masks, gowns and gloves. During period II these procedures were abolished, but hands were cleansed using alcohol and masks were worn during both periods in case of coughing and sneezing. All CoNS strains isolated from blood cultures were genetically classifies by pulsed field gel electrophoresis (PFGE). The incidence of CRI during period I was 13.0 per 1000 catheter days, in comparison to 9.6 in period II (P=0.84). During this latter period, 19 CRI were diagnosed, 14 catheter related bacteremia episodes (CRB) and five local infections. Seventy-two percent (n=9) of CRB were due to a CoNS. The mean catheter survival until appearance of a CRI increased from 43 days during period I to 78 days in period II (P=0.39). The mean catheter survival until infection related removal was increased from 43 days to 133 days (P=0.12). During period I less experienced intervention radiologists introduced the catheters, which may have limited the efficacy of the strict hygiene measures. Thus, abolishing strict isolation precautions had no negative effect on the incidence of CRI. After genotyping of 38 MRSE strains isolated from blood and central venous catheter cultures of 12 patients in period II, eight PFGE types were found. Three types were found in more than one patient, but based on epidemiological data patient-to-patient spread could not be proven. No genotypic identity between patient and personnel CoNS isolates was shown and the two major clonal types that were present between 1994 and 1996 were not encountered. However, from December 1998 onwards new MRSE clones could be identified (types E and J). In conclusion, despite a constant rate of CRI and implementation of optimal patient care, clonal spread of MRSE strains was not prevented by strict hygiene measures.     

Antibioticograms of Vibrio cholerae non-01/non-0139 strains isolated from humans within 1968-2009

Analysis of the antibioticograms of the Vibrio cholerae non-01/non-0139 strains showed that in the cultures isolated in the Rostov Region in 1968--1975 there were present markers of resistance to ampicillin (7%), kanamycin (15.8%), rifampicin (3.5%) and trimetoprim/sulfamethoxazole (14%). Among the strains isolated in the Ukraine in 1975 14% was resistant to ampicillin. More than a half of the strains isolated in Uzbekistan in 1990 and 2000-2001, in the Arkhangelsk Region in 1999-2000 and in the Kalmykia in 1999-2005 was antibiotic resistant. In the above regions the strains were resistant to ampicillin (12.5-44.4%), kanamycin (11-55%), rifampicin (1.9-12.5%) and trimetoprim/sulfamethoxazole (25-62.5%). Among the cultures isolated in Uzbekistan in 1990 and 2000-2001 25 and 7.8% were resistant to furazolidone and 31.25% was resistant to streptomycin (1990). All the cultures isolated in the Rostov Region in 2005-2009 were resistant to ampicillin, 50% was resistant to ceftazidim, 57% was resistant to streptomycin and furazolidone, 7.2% was resistant to kanamycin and 14% was resistant to trimetoprim/sulfamethoxazole. The studies revealed an increase of the extent of the V.cholerae non-01/non-0139 resistance spectrum within 1968-2009, simultaneous presence of up to 5 diverse resistance markers and a variety of their combinations, that requires the use of antibacterials for the treatment of the diseases due to the vibrios in strict compliance with the pathogen antibioticogram and their early replace by more efficient drugs.     

Yeast-like fungi as etiologic agents of blood infections in patients hospitalized in 1998-1999

The aim of the study was the analysis of frequency of yeast-like fungi as etiological agents of fungemias in patients hospitalized in operative and conservative wards of Medical Academy Central Clinical Hospital in Warsaw in 1998-1999. Peripheral blood samples and collected from vascular catheters were incubated in BacT/Alert system(Organon Teknika, USA). Positive blood samples were inoculated on Sabouraud medium with chloramphenicol (bioMerieux, France) (the time of cultivation from 48 h to 7 days at 30 C) and on chromogenic medium BBL CHROMagar Candida (Becton Dickinson, USA). Fungal strains were identified by standard mycological procedures using ID 32 C strips (ATB system, bioMerieux, France) and tests of Sanofi Diagnostics Pasteur (France). The total number of positive blood cultures was 1724. Fifty eight fungal strains were isolated from blood samples (3.36%). Strains belonged to 4 genera: Candida (55), Trichosporon (1), Saccharomyces (1) and Pichia (1). Thirty eight fungal strains were isolated from peripheral blood samples. Forty seven fungal strains were cultured from patients hospitalized in operative wards. Among fungi isolated from peripheral blood samples C. albicans (10), C. glabrata (9) and C. parapsilosis (5) strains dominated. From blood samples collected from vascular catheters most often C. albicans (7), C. glabrata (4) and C. parapsilosis (3) were isolated.     

Decrease in anaerobe-related bacteraemias and increase in Bacteroides species isolation rate from 1998 to 2007: A retrospective study

Conflicting data have accumulated in recent years regarding the incidence of anaerobic bacteraemias. The aim of this study was to determine the prevalence of bacteraemias due to anaerobic bacteria and evaluate the importance of anaerobic blood cultures in a university hospital in Israel. A retrospective survey which focused on anaerobic blood culture bottles was performed on blood cultures received in our laboratory during the decade from January 1998 to December 2007. Anaerobic-related bacteraemias decreased during that period, whereas a significant increase was observed in Bacteroides species isolated from the blood cultures (from 18% during 1998–2002 to 43% during 2003–2007). Comparison of the medical records of 54 patients with Bacteroides-related bacteraemia during the two end periods (1998–1999 and 2006–2007) revealed a marked increase in complex underlying diseases. Hypertension and diabetes mellitus type II were found in 29% of the patients in 1998–1999 and increased to 43–45% of the patients in 2006–2007. Ischemic heart disease also increased from 14% of the patients in 1998–1999 to 43% in 2006–2007. We conclude that although positive anaerobic blood cultures account for a small percentage of positive blood samples, the growing involvement of Bacteroides species-related bacteraemias together with an increase in complex underlying diseases in these patients emphasize the importance of anaerobic blood cultures, particularly in patients with co-morbidities.     

Optimal collection of blood samples for the measurement of tumor necrosis factor alpha

We have examined how delayed separation of plasma from cells affects the recovery of recombinant human tumor necrosis factor alpha (rhTNF alpha) from whole blood. Storage of heparinized whole blood samples at room temperature for 1 hr results in a significant (p = 0.036) fall in recovery of plasma TNF alpha from 788 +/- 119 pg/mL to 472 +/- 77 pg/mL, measured by specific enzyme-linked immunosorbent assay (ELISA). Storage of whole blood samples at 4 degrees C for 1 hr reduces but does not prevent the fall in recovery of plasma TNF alpha: 725 +/- 82 pg/mL at time 0, 472 +/- 81 pg/mL after 1 hr, p = 0.038. Recovery of bioactive TNF alpha (cytotoxocity for L929 cells) after 1 hr at room temperature is also significantly reduced from 576 +/- 139 pg/mL to 450 +/- 154 pg/mL, p = 0.036. Studies with 125I-rhTNF alpha confirmed the fall in plasma activity and revealed a rapid commensurate increase in 125I-rhTNF alpha activity in the cell fractions. We recommend that clinical samples for the measurement of cytokines should be kept at 4 degrees C and separated rapidly (within half an hour) before storing the plasma at -70 degrees C.     

Antibiotic utilization and Pseudomonas aeruginosa resistance in intensive care units

Pseudomonas aeruginosa is one of the most frequent and dangerous pathogens involved in the etiology of severe nosocomial infections. A retrospective observational study was conducted at all intensive care units of the University Hospital in Olomouc, Czech Republic (155 ICU beds). Complete antibiotic utilization data of the ICUs in the period of 1999 to 2008 were processed according to ATC/DDD system and expressed in defined daily doses per 100 bed-days (DBD). Utilization of meropenem, imipenem, ciprofloxacin, ofloxacin, pefloxacin, gentamicin, amikacin, ceftazidime, cefoperazone, cefoperazone/sulbactam and piperacillin/tazobactam was measured. Pseudomonas aeruginosa strains were isolated from clinical material obtained from patients hospitalized in ICUs. During the ten-year period, utilization of the entire group of antibiotics monitored grew. It increased from 23.52 DBD in 1999 to 27.48 DBD in 2008 with a peak of 33.04 DBD in 2007. P. aeruginosa accounted for as much as 42% of pneumonias and 23% of surgical wound infections. Our results show that P. aeruginosa strains became gradually resistant to all antibiotics used in the treatment of the infections caused by them, with the exception of amikacin and piperacillin/tazobactam.     

Clinical and Therapeutic Aspects of Candidemia: A Five Year Single Centre Study

BackgroundCandida is an important cause of bloodstream infections (BSI) in nosocomial settings causing significant mortality and morbidity. This study was performed to evaluate contemporary epidemiology, species distribution, antifungal susceptibility and outcome of candida BSI in an Italian hospital.MethodsAll consecutive patients who developed candidemia at Santa Maria della Misericordia University Hospital (Italy) between January 2009 and June 2014 were enrolled in the study.ResultsA total of 204 episodes of candidemia were identified during the study period with an incidence of 0.79 episodes/1000 admissions. C. albicans was isolated in 60.3% of cases, followed by C. parapsilosis (16.7%), C. glabrata (11.8%) and C. tropicalis (6.4%). Of all Candida BSI, 124 (60.8 %) occurred in patients admitted to IMW, 31/204 (15.2 %) in ICUs, 33/204 (16.2%) in surgical units and 16/204 (7.8%) in Hematology/Oncology wards. Overall, 47% of patients died within 30 days from the onset of candidemia. C. parapsilosis and C. glabrata candidemia were associated with the lowest mortality rate (36%), while patients with C. tropicalis BSI had the highest mortality rate (58.3%). Lower mortality rates were detected in patients receiving therapy within 48 hours from the time of execution of the blood cultures (57,1% vs 38,9%, P <0.05). At multivariate analysis, steroids treatment (OR= 0.27, p=0.005) and CVC removal (OR=3.77, p=0.014) were independently associated with lower and higher survival probability, respectively. Candidemia in patients with peripherally inserted central catheters (PICC) showed to be associated with higher mortality in comparison with central venous catheters (CVC, Short catheters and Portacath) and no CVC use. For each point increase of APACHE III score, survival probability decreased of 2%. Caspofungin (OR=3.45, p=0.015) and Amphothericin B lipid formulation (OR=15.26, p=0.033) were independently associated with higher survival probability compared with no treatment.     

Occurrence and susceptibility to antibiotics of carbapenem-resistant Pseudomonas aeruginosa strains between 1998 and 2009

P. aeruginosa rods are dangerous pathogens mainly responsible for nosocomial infections of different localization. Resistance to carbapenems, observed among them, is a serious threat due to ability to be transmitted between bacterial species. The aim of our study was to retrospectively evaluate the frequency of isolation and susceptibility to antibiotics of imipenem- and meropenem-resistant P. aeruginosa strains isolated between 1998 and 2009 from patients of University Hospital No 1 of dr A. Jurasz in Bydgoszcz. Study shows increasing number of isolation that type of strains from 19 in 1998 to 144 in 2009. Among all isolated P. aeruginosa strains majority was obtained from patients of the Intensive Care Units, Rehabilitation and Surgery Clinics. Examined strains of P. aeruginosa rods were mainly isolated from urine (20.5%), bronchoalveolar lavage (17.7%) and wound swabs (14.5%) samples. The isolates demonstrated frequently resistance to carbenicillin (> or 66.7%), ticarcillin (> or = 72.7%) and cefotaxime (> or = 75.6%). The lowest rate of resistant strains was observed in case of ceftazidime (< or = 68.8%), aztreonam (< or = 47.4%) and colistin (< or = 1.7%) suggesting the highest activity of that antimicrobials against infections caused by examined strains.     

Analysis of microorganisms isolated from febrile neutropenic children with neoplastic disease

The microbiological evaluation of the blood was carried out as a continued monitoring of the microorganism culture using the colourmetric system VITAL 200 (bio-Mérieux). There have been analysed 4660 bacteriological research results of the peripheral blood, blood from Broviac and from Broviac liquid of the children suffering from cancer treated in the years 1997-2000 in the Pediatric, Hematology and Oncology Clinique of the State Clinical Hospital in Bydgoszcz. There have been gained 1032 positive cultures from KZZ, KZB, PZB. There have been recognized 259 bacteremia and 22 fungemia by the children with fever in the neutropenia period. In the analysed four years in the blood dominated Gram-positive bacteria. Among Gram-positive bacteria there were mostly Staphylococcus spp. (42.5%), mostly CNS, fewer numerous were Streptococcus spp. (14.5%) and Corynebacterium spp. (5.9%). Among Gram-negative bacteria mostly were isolated Acinetobacter spp. (25.6%), Pseudomonas spp. (9.7%), E. coli (13.8%), Enterobacter spp. (13.9%), Klebsiella spp. (9.2%). There were observed few infections by strains resistant to many antibiotics, S. maltophilia, B. cepacia, E. faecium, S. haemolyticus. All strains Staphylococcus spp. were sensitive to vancomycin. There have not been found Enterococcus spp. resistant to glycopeptides. Most active against Gram-positive rods were carbapenems and aminoglycosides.     

The drug sensitivity of meningococci and the characteristics of its determination

The results obtained in the study of antibiotic and sulfamide sensitivity of 197 Neisseria meningitidis strains of groups A, B and C, isolated from the spinal fluid and blood of patients with meningococcal infection hospitalized in the 2nd Clinico-Infectious Hospital, Moscow, in 1984-1989 and studied with the use of the disc diffusion method and the method of serial dilutions of antibiotics in solid culture media, are presented. As revealed in this study, N. meningitidis strains retained their high sensitivity to penicillin and ampicillin (MIC50 = 0.016 and 0.032 micrograms/ml respectively). Sensitivity to tetracycline decreased (MIC50 = 0.5 micrograms/ml) and to rifampicin increased (MIC50 = 0.063 micrograms/ml). 48.5% of strains were resistant to streptomycin. In recent years the proportion of N. meningitidis, resistant to sulfanilamide preparations, significantly decreased and MIC50 was equal to 2.5 micrograms/ml in comparison with 5-10 micrograms/ml in the preceding period. The results of testing sensitivity to antibiotics by both methods coincided. Still the disc diffusion method can be used in epidemiological surveillance on meningococcal infection, while for more exact differentiation of N. meningitidis strains the use of the method of serial dilutions is necessary.     

Characterization of the effects of human placental HGF on rat hepatocytes.

Hepatocyte growth factor (HGF) also known as hepatopoietin A (HPTA) (Michalopoulos, FASEB J., 4:176-187, 1990) is a heparin-binding growth factor whose characterization and tissue distribution have been reported elsewhere. This growth factor was recently cloned and its amino acid sequence determined under the name of hepatocyte growth factor (HGF) (Miyazawa et al., Biochem. Biophys. Res. Commun., 163:967-973, 1989; Zarnegar et al., Biochem. Biophys. Res. Commun., 163:1370-1376, 1989; Nakamura et al., Nature, 342:440-443, 1989). Human placenta is one of the tissues that contains significant amounts of HGF. We isolated HGF from human placenta and characterized its biologic effect on rat hepatocytes. Human placenta HGF was isolated in high purity as a single chain molecule. Single chain HGF stimulated DNA synthesis in primary rat hepatocyte cultures in serum-free medium. The maximal effect was seen at 5-10 ng/ml. The maximal response occurred at 25-48 hours after plating of the hepatocytes. Protein synthesis was also stimulated by HGF in primary rat hepatocyte cultures. There were peak responses at 19-24 and 37-42 hours after plating of the hepatocytes. TGF beta 1 inhibited more than 95% of HGF-induced DNA synthesis but only 25% of HGF-induced protein synthesis. HGF interacted in an additive manner with EGF, a well-known hepatocyte mitogen. There was not an additive interaction between HGF and aFGF. Regenerating liver hepatocytes obtained from rats which underwent two-thirds partial hepatectomies (PHX) also responded to HGF in a dose-dependent manner as the hepatocytes from normal liver.     

The role of preoperative antibiotic prophylaxis in cosmetic surgery

An estimated 2.7 million cosmetic procedures were performed in the United States in 1998, yet the role of preoperative antibiotic prophylaxis for cosmetic surgery is not clearly defined. Routine antibiotic prophylaxis for cosmetic procedures was discontinued by the senior author at the authors' institution in an effort to reduce use and cost in June of 1999. Subsequently, a cluster of four Staphylococcus aureus postoperative surgical site infections were identified. A case-control study to identify risk factors for surgical site infections in these patients was performed. All patients who underwent cosmetic surgical procedures by the senior author during June of 1999 and did not develop a surgical site infection were selected as control patients. Four case patients and 12 control patients were included in the study. The significant risk factors associated with surgical site infections were the mean duration of procedure (5 hours versus 2 hours; p = 0.02), general anesthesia (p = 0.004), and placement of a Blake drain (p = 0.004). No common source of infection was identified by review and observation of surgical technique. Pulse-field gel analysis of the S. aureus isolates from the four case patients and the nares of surgical personnel revealed no common strain. After the reinstitution of preoperative antibiotic prophylaxis with cefazolin for procedures anticipated to last 3 hours or longer, no additional surgical site infections were identified through December of 1999 (four of 29 versus none of 104; p = 0.002). It was concluded that targeted antibiotic prophylaxis for cosmetic surgery with cefazolin may be useful in reducing surgical site infections attributable to S. aureus.     

Extracellular slime production and adhesion of Morganella morganii strains to polystyrene

The aim of this study was the evaluation of the ability of extracellular slime production and adhesive properties of M. morganii strains. This study included 50 of M. morganii strains isolated from clinical samples. All of these strains were isolated in the Clinical Microbiology Department of dr. A. Jurasz University Hospital in 2008-2009. Five (10.0%) out of 50. M. morganii strains demonstrated extracellular slime production. Adherence to polystyrene revealed 36 (72.0%) of M. morganii strains in it 6 strains (12.0%) adhered strongly, medium - 12 (24.0%) and weakly - 18 (36.0%).     

The herald waves of influenza virus infections detected in Sendai and Yamagata cities in 1985-1990

The community surveillance of respiratory virus infections performed during 1985-1987 in Sendai and 1988-1990 in Yamagata has identified a total of five herald waves of influenza virus infections: A/H3N2 virus infections in 1985 and 1989, A/H1N1 virus infections in 1986 and 1988, and type B virus infections in 1989. To investigate the antigenic and genetic relationships between the herald wave and epidemic strains, influenza A/H1N1 viruses isolated during the 1986 and 1988 herald waves were compared with those isolated during the 1986-1987 and 1988-1989 epidemic seasons, respectively, utilizing hemagglutination inhibition tests with anti-hemagglutinin monoclonal antibodies and oligonucleotide mapping of total viral RNAs. The results showed that multiple variants differing in antigenic and genetic properties were cocirculating during the 1986 herald wave as well as during each of the two epidemics (only one strain was isolated in the 1988 herald wave). It was also observed that viruses which had the antigenic and/or genetic characteristics closely similar to those of the viruses circulating in the 1986 and 1988 herald waves, were isolated during the winters of 1986-1987 and 1988-1989, respectively.