Measles and mumps are highly contagious, vaccine-preventable diseases with cases continuing to persist in high two-dose vaccinated populations. Recent outbreaks on university and college campuses across the United States prompt a need for further understanding of the immunity levels afforded by the MMR vaccine which has significantly decreased incidence rates of measles and mumps since it was introduced.
Current methods for IgG antibody detection include enzyme immunoassays (EIA) such as the commercially available Diamedix Immunosimplicity® Measles IgG test kit and the Diamedix Immunosimplicity® Mumps IgG test kit. EIAs generally provide high sensitivity and strong specificity, however, there is a need for rapid screening of measles and mumps specific immunity in outbreak and resource-limited areas which could be solved by use a point-of-care (POC) platform.
This study aims to optimize a point-of-care device for the multiplexed detection of MeV, MuV, and RuV IgG antibodies in sera and to compare the sensitivity to commercial enzyme immunoassays. The IgG antibody levels to MeV and MuV were measured using EIA test kits for a total of 44 healthy serum samples. Of the samples, 6% were seronegative for MeV-specific IgG antibodies and 75% were seronegative for MuV-specific antibodies, showing low correlation of IgG antibody levels between both viruses.
To improve the sensitivity of the POC device, multiple conjugated fluorescent secondary antibodies were tested with different surface chemistries. Signal detection was measured using the pre-developed four-site slide reader. Preliminary data show that Nile Red microspheres provide robust signal detection and should be the secondary antibody of choice when sera are tested for IgG antibodies using the POC platform in future work.