Tick-borne encephalitis (TBE) is a viral infectious disease, which affects Central Nervous System, caused by an arbovirus from the family Flaviviridae. Reservoir hosts of the virus are forest animals and the transmission, to humans and animals, occurs through tick bites or, exceptionally, by consumption of infected heat untreated milk. Up to 70% of infections are clinically inapparent or with mild symptoms; in the remaining 30% of cases, after an incubation period of 3-14 days, nonspecific flu-like symptoms occur. After some days of remission, the second phase of the disease develops. This phase is characterized by aggravated headaches, ophtalmoplegia, vomiting, malaise, meningeal symptoms, cranial nerve paralysis and paresis of the limbs. An acute stage of tick-borne encephalitis lasts 1 to 3 weeks. More severe course of the disease, often with lasting ill effects, can be observed in senior patients.
The diagnosis is based on anamnesis, clinical picture and results of laboratory tests such as the detection of specific IgM and IgG antibodies. The IgG antibodies protect the organism against a new infection and they can be detected over a long period (several years) after the past infection or vaccination. The IgM antibodies are serological markers of acute infection and their production can last up to 10 months.
Immunoenzymatic method for the qualitative determination of IgG and IgM-class antibodies to Tick-borne Encephalitis Virus in human serum, using a disposable device applied on the Chorus and Chorus TRIO instruments.The test is based on the ELISA principle (Enzyme Linked ImmunoSorbent Assay) which uses the reaction between the antibodies present in the tested sample and the immobilized antigen bound to solid phases.The immunoglobulins bind to the antigen through incubation with diluted human serum.The disposable devices contain all the reagents to perform the test when applied on the Chorus instruments. The result is expressed as an INDEX (ratio between the OD value of the sample and that of the Cut-off).