The objective of the project is to develop simplified tests for the diagnosis of measles infection (IgM) and of measles immunity (IgG) which can be carried out under field conditions by health personnel after short training, and which meets WHO standards. Such diagnostic tests are presently not available, but are urgently needed for the implementation of WHO measles control and eradication programmes. Therefore the development is recommended by the WHO. Common commercial measles ELISAs are based on whole virus as antigen or measles virus infected whole cells. Such antigens are not suitable for the development of simplified field tests. Recombinant antigens derived from measles virus proteins which are produced in a mammalian high expression system has been developed. Antigens were extensively tested in conventional ELISAs and proved to be highly effective for measuring measles-specific IgG antibodies in serum and its properties seemed to be compatible with the development of a field test. These recombinant proteins are also highly reliable for the detection of IgM of measles patients. Comparative studies with ELISAs based on whole measles demonstrate that the sensitivity and specificity of both assays are similar with respect to specific IgG and IgM. On the basis of these results rapid field tests will be developed. The feasibility of such a rapid test has already been demonstrated for a number of infectious agents including Hepatitis B and HIV. Such rapid tests should be able to measure antibodies in serum as specific as a conventional enzyme immuno assay, however requiring less time and equipment.
The objective is therefore to bring essentially two technologies together to produce a rapid field test for measles. The two technologies are - A recombinant antigen derived from the MV that has been demonstrated in conventional ELISAs to be highly effective for measuring measles-specific IgG antibodies in serum as a parameter of measles immunity and of serum IgM for measles diagnosis; - A proprietary rapid test technology based on immunochromatography that measures antibodies in serum as specific as a conventional enzyme immuno assay.