RESPIRATORY SYNCYTIAL

The Respiratory Syncytial Virus (RSV) is the major cause of respiratory acute infections during infancy and childhood. Most of the infections caused by RSV occur during the first 6-12 months of life, often as sudden seasonal epidemics. The RSV can be considered the virus with the highest rate of morbility in early childhood because of the severe illnesses caused (bronchiolitis, pneumonia), even resulting in death, especially in those patients affected by other severe pathologies.
The RSV is ubiquitous in all parts of the world and causes respiratory infections primarily in children, in all the climate zones and with similar symptomatology. The annual epidemics are sudden, generally have short duration and a regular and predictable course. In temperate climates the epidemics occur between December and April, with a peak in February and March. In tropical climates the epidemics usually occur during the rainy season.
The determination of IgG class antibodies in adults, not only permits observations of epidemiologic type, but also will confirm the presence of infection in progress. A high IgG titer or a significant increase of IgG between two samples taken approximately 2 weeks apart confirm that there is an infection in progress.
On the contrary in children it was observed that the IgG antibody response is not relevant, especially during their first year. In the case of acute infection in children a response of IgA class antibodies is mainly found. Indeed 87% of children with an infection in progress present a high rate of IgA, while only 20% present IgG class antibodies.

Method:

Immunoenzymatic method for the qualitative determination of IgG and IgA-class antibodies to Respiratory Syncytial 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).