The European network of Biosafety-Level-4 laboratories: enhancing European preparedness for new health threats.

Emerging and re-emerging infections and possible bioterrorism acts will continue to challenge both the medical community and civilian populations worldwide, urging health authorities to respond rapidly and effectively. Established in 2005, the European Community (EC)-funded European Network of Biosafety-Level-4 laboratories (Euronet-P4), which brings together the laboratories in Porton Down, London, Hamburg, Marburg, Solna, Lyon and Rome, seeks to increase international collaboration in the areas of high containment laboratory biosafety and viral diagnostic capability, to strengthen Europe's capacity to respond to an infectious disease emergency, and to offer assistance to countries not equipped with such costly facilities. Network partners have agreed on a common strategy to fill the gaps identified in the field of risk group-4 agents' laboratory diagnosis, namely the lack of standardization and of reference samples. The network has received a further 3-year funding, to offer assistance to external laboratories, and to start the planning of field activities.

Facing the threat of highly infectious diseases in Europe: the need for a networking approach.

In recent years emerging and re-emerging infections, as well as the risk of bioterrorist events, have attracted increasing attention from health authorities because of the epidemic potential that renders some of them a real public health challenge. These highly infectious diseases (HIDs) are occurring more and more frequently in Europe, and despite the many initiatives in place to face them, many unsolved problems remain, and coordinated efforts for dealing with HIDs appear mandatory. Whereas uncoordinated measures would lead to only partial and poor responses to these emerging threats, networking represents a valuable approach to these diseases, in order to: (i) ensure a rapid and effective response; (ii) stimulate complementarity and prevent duplication; (iii) promote international cooperation, exchange of experience, good practice and protocols; and (iv) support the less prepared countries in the European Community.

Macrorestriction analysis of Pseudomonas aeruginosa in colonized burn patients.

The colonization of hospitalized patients by Pseudomonas aeruginosa at an intensive care unit for burn victims was studied over a one-year period. A total of 231 isolates from 12 patients were analyzed by macrorestriction analysis. The results revealed that most patients were infected with only one to three different strains. In several patients Pseudomonas aeruginosa isolates of the same clonal lineage exhibited considerable differences in their macrorestriction fragment pattern. Digestion with further restriction enzymes, however, allowed differentiation between clonal variants due to a high genetic drift and superinfection with a different Pseudomonas aeruginosa strain. Isolates of the same clonal lineage could be isolated from several patients as well as from the patients' environment. Notably, Pseudomonas aeruginosa could be isolated from sedimentation plates. Thus, patients may have been extensively cross-infected on the ward. These data underline the importance of strict infection control measures and of regular surveillance for Pseudomonas aeruginosa by an appropriate typing method, i.e. one that can differentiate strains with high genomic variability.

Risk of bacteremia induced by transesophageal echocardiography: analysis of 100 consecutive procedures.

The incidence of bacteremia induced by transesophageal echocardiography (TEE) and, consequently, the need for an antibiotic prophylaxis before TEE is still controversial. Therefore, we studied the incidence of bacteremia associated with TEE prospectively in 100 consecutive patients without clinical or laboratory signs of bacterial infection. Blood samples were drawn immediately before and at 0, 5, and 15 minutes after TEE. In addition, swabs were taken from the pharyngeal region before TEE and from the distal part of the TEE-probe before and after TEE. All blood cultures taken before TEE remained sterile. After TEE, three positive blood cultures were found in two patients: the first patient had two different species of coagulase-negative staphylococci in cultures taken at 0 minutes (Staphylococcus capitis) and 15 minutes (Staphylococcus cohnii) after TEE, whereas the sample taken after 5 minutes remained sterile. In the second patient, Propionibacterium species appeared after 7 days of processing in a culture taken immediately after TEE, but not in the samples taken after 5 and 15 minutes. None of the three microorganisms found in the blood were simultaneously isolated in pharyngeal specimens or TEE-probe specimens of the same patient. Thus positive blood cultures in both patients were considered contaminated. This study demonstrates that TEE, when performed by an experienced investigator, is not associated with an increased risk of bacteremia. Accordingly, it is justified to perform TEE examinations (also in high-risk patients) without antibiotic prophylaxis.

Frequency of occurrence and characterization of catalase negative Campylobacter isolated from human feces in Vienna.

Of a total of 124 Campylobacter (C.) strains isolated 1988 from fecal specimens, 4 (3.2%) were catalase-negative. Two strains were catalase-negative variants of C. jejuni. The other two were identified as C. upsaliensis on the basis of their biochemical properties and of the results of DNA-DNA hybridization with biotinylated probes from C. upsaliensis and C. jejuni. Both had been isolated from patients after their return from Asia (India and Thailand, respectively). In one case, a significant decrease of the antibody titre was observed within 12 months when the patient strain was used as an antigen. Since this patient had been suffering from diarrhoea during her stay and since with the exception of amoebic cysts, no other intestinal pathogen was isolated, C. upsaliensis is thought to have been the reason for the diarrhoeal episode.

[Dental care of HIV carriers]. / Zahnbehandlung bei HIV-Tragern. Probleme--Massnahmen--Konzepte.

As HIV infections continue to spread worldwide, the number of patients with known or unknown HIV positivity seen in dental practice is increasing. Some of the infected individuals need more frequent dental care than the general population, because HIV infections tend to be associated with specific oral manifestations. HIV-positive individuals have special psychosocial problems attributable both to their disease and to their frequent association with socially discriminated groups. These problems are also reflected in the dentist-patient relationships. Dental care of known HIV-positive individuals is much less hazardous than the treatment of undiagnosed HIV carriers. Building confidence between the dentist and the patient is essential. As HIV transmission is similar to that of hepatitis B, the full battery of hygienic precautions established for preventing hepatitis B should be observed in dental work to prevent HIV infections. Conditions of work in dental offices should meet the hygienic standards needed to preclude the risk of infections both for the dentists and their patients.

Infections following tickbites. Tick-borne encephalitis and Lyme borreliosis--a prospective epidemiological study from Tyrol.

We present here a prospective study on infections following tickbites in military recruits in the province of Tyrol (Austria). 84 recruits experienced tickbites and underwent clinical and serological examination twice at four-week intervals for signs of tick borne encephalitis (TBE)-virus or Borrelia burgdorferi infections. 56 and 50 recruits could be evaluated for TBE-virus and Borrelia infection, respectively. Whereas no recruit was found with clinical or laboratory evidence of TBE-virus infection, two (4%) recruits showed an erythema chronicum migrans as primary manifestation of a Borrelia burgdorferi infection and 11 (20%) recruits had a significant increase in the titer of anti-Borrelia burgdorferi antibodies. Our results support the predominance of a subclinical course of a tick-transmitted borrelia infection in the population under observation, and shed some light on the epidemiological situation of tick-transmitted diseases in Tyrol.

Comparison of different antigen preparations in an evaluation of the immune response to Campylobacter pylori.

This study presents a novel approach to the analysis of protein antigens of Campylobacter pylori for use in serology. Protein fractions of this bacterium were resolved in polyacrylamide gel electrophoresis, eluted from gel strips in an electric field and used for coating of microtiter plates in an ELISA-type assay run with a small set of sera from both infected and non-infected patients. Reactivity and discriminative power of the different fractionated antigens (1-9) and crude antigen preparations (A-C) were compared. Better discrimination was achieved between positive and negative sera with high molecular weight fractionated preparations (antigens 8 and 9) than with low molecular weight fractions. Among the crude antigen preparations, antigens A (sonicated whole cells) and C (ultracentrifugated sonicate) seem to have a better discriminative power than antigen B (acid glycin extract).

The efficacy of antimicrobial treatment in Campylobacter pylori-associated gastritis and duodenal ulcer.

The efficacy of various antimicrobial and anti-ulcer agents on the elimination of Campylobacter pylori in duodenal ulcer patients was investigated. Ranitidine, cimetidine, pirenzepine, aluminium phosphate gel as well as combinations of H2-receptor antagonists or pirenzepine + penicillin V, ciprofloxacin, ofloxacin, phenyl-mercuryborate or rifampicin had no influence on C. pylori in vivo. Short term elimination of C. pylori was achieved in 3/15 patients treated with ranitidine + bacampicillin and in 1/5 treated with cimetidine + metronidazole. This elimination was accompanied by a significant reduction of polymorphonuclear infiltration of the antral mucosa. Development of bacterial resistance was observed in patients with additional quinolones, metronidazole and rifampicin but not in patients treated with betalactam antibiotics.

A monoclonal antibody (GF 22.1) detecting different patterns of HLA class I cross-reactivities at different dilutions.

A murine cytotoxic monoclonal antibody (GF 22.1) was produced by Balb/c immunization with GRA human lymphoblastoid cells. HLA-A, B and C blanketing and SDS-PAGE analysis of the immunoprecipitate demonstrated MHC class I structures as the targets. Cytotoxic assays were performed with peripheral blood lymphocytes from 84 unrelated donors and from members of 15 families at different antibody dilutions. Statistical analysis was performed by Fisher test on each dilution separately and by Mann-Whitney U test on the dilutions taken all together. The data suggest the detection of a cross-reacting group (B15, A32, B17, B40/w41 and B21) with high affinity and the inclusion of other antigens (B12, B35, A2, B13, A11 and A24) with a lower affinity.