Solid-phase immunosorbent haemadsorption (SPIHAd): a new, rapid and simple test for rubella-specific IgM

Area of Science:

• Virology
• Immunology
• Diagnostic Assays

Background:

• Rubella virus infections require accurate serological diagnosis.
• Detecting rubella-specific IgM is crucial for diagnosing acute infections.
• Existing methods for rubella IgM detection can be cumbersome and require serum pretreatment.

Purpose of the Study:

• To develop and evaluate a new, rapid, and sensitive test for rubella-specific IgM.
• To compare the performance of the new test against a gold standard method.
• To assess the utility of the test for detecting IgM from both natural and vaccine-induced rubella infections.

Main Methods:

• Development of a solid-phase immunosorbent haemadsorption (SPIHAd) assay for rubella-specific IgM.
• Comparison of the SPIHAd test with sucrose density gradient fractionation and haemagglutination inhibition.
• Testing of serum samples from individuals with natural rubella infection and rubella vaccination.

Main Results:

• The SPIHAd test demonstrated high sensitivity in detecting rubella-specific IgM from natural infections.
• The test showed variable results in detecting rubella vaccine-induced IgM.
• The SPIHAd test does not require serum pretreatment and is unaffected by rheumatoid factor or rubella-specific IgG.

Conclusions:

• The developed SPIHAd test is a rapid, sensitive, and cost-effective method for diagnosing rubella-specific IgM in natural infections.
• The test offers practical advantages including handling large numbers of untreated sera.
• Further refinement may be needed to improve sensitivity for vaccine-induced rubella IgM detection.