Absorption of IgG with Staphylococcus aureus in a diagnostic test for IgM antibodies to Japanese encephalitis, West Nile & dengue viruses
George, S.; Reddy, M.V.; Yergolkar, P.N.; Pavri, K.M.
Indian Journal of Medical Research 84: 239-246
1986
ISSN/ISBN: 0019-5340 PMID: 3817923 Document Number: 279198
Sera from patients of encephalitis from Kolar, Mandya and Bangalore districts and human survey sera from Mandya district of Karnataka State were tested for the presence of virus specific IgM antibodies to Japanese encephalitis (JE), West Nile (WN) and dengue (DEN-2) viruses. The sera were absorbed with Staph. aureus for removal of IgG and then tested in HI test. Among the 37 pairs tested, IgM was detected in 31 pairs-monotypic in 25 and heterotypic in 6. Among the 82 single sera tested, monotypic IgM was detected in 50 sera and heterotypic IgM was detected in 16. Of the 52 survey sera tested, only 10 had virus specific IgM-6 monotypic and 4 heterotypic. The reasons for the presence of cross reacting IgM in some cases and the lack of IgM in a few other clinically proved cases of encephalitis and the significance of JE virus specific IgM in survey sera are high-lighted. The procedure employed is simple and useful in the detection of IgM antibodies in flavivirus infections.