A survey on cases of tick-borne encephalitis in European countries.

The European Network for Diagnostics of "Imported" Viral Diseases (ENIVD) is finalising a project to improve the diagnostic and monitoring of encephalitis viruses in Europe. Part of this study was to analyse the present surveillance situation for tick-borne encephalitis (TBE), which is the most important flavivirus infection of the central nervous system in the European Union (EU) and Russia. A questionnaire was mailed to contact points in all Member States of the EU and three non-EU countries (Norway, Russia and Switzerland) to summarise their TBE surveillance and prevention activities. Information was requested on case definition, type of laboratory tests for TBE diagnostics, investigations regarding tick-transmitted diseases, mapping of endemic foci, vaccination programmes, and recommendations for travellers. The survey gives an overview of the existing epidemiological and laboratory sources of information and the number of TBE cases from 2004 until 2007, but also showed that, in particular, case definitions, diagnostic assays for confirmation, and methods/indicators for mapping risk areas differ widely across the participating countries. The data will help to develop recommendations for the standardisation and quality control or TBE surveillance and diagnostics.

Isolation and characterization of a 14500 molecular weight protein from brains and tissue cultures persistently infected with borna disease virus.

A protein with an apparent molecular weight of 14500 (14.5K) was extractable from homogenates of Borna disease virus-infected brains and tissue cultures using high concentrations of detergent and salt and by differential centrifugation procedures. The protein, present in an aggregated form, was remarkably resistant to proteinase K. Specific antibodies prepared in the homologous system (rat) recognized the 14.5K protein from various sources (infected brain of rat, mouse or chicken, and tissue cultures), but did not neutralize infectivity nor stain Borna disease virus-specific antigens from in vitro or in vivo preparations. Post-infection immune sera from different animal species did not detect the protein. This 14.5K protein was infection-specific but not disease-specific, and is inferred to be part of an internal virion component.

Study on a proteolytic enzyme from Trypanosoma congolense. Purification and some biochemical properties.

A protease has been purified from Trypanosoma congolense bloodstream forms by osmotic disruption, freeze-thawing of the cells, followed by chromatography using Thiopropyl-Sepharose and gel filtration. The enzyme is a thiolprotease. A combination of SDS-polyacrylamide gel electrophoresis and contact print zymograms using casein as substrate showed a single proteolytic band with a molecular weight of 31 000. The isoelectric point of the enzyme as ascertained by isoelectric focusing extended from pH 4.4 to 5.5 with a maximum at pH 5.0. The protease cleaved various heat denatured substrates such as casein, hemoglobin, albumin and ovalbumin. The highest enzyme activity was observed at pH 5.5 and pH 6.0 using casein and hemoglobin as substrates respectively. The max. temperature was found to be 50 degrees C. The enzyme is inactivated by mercurial compounds, iodoacetamide, iodoactate, chloromethylketones and leupeptin and is activated by dithioerythritol.