Highly sensitive zika and dengue antigen antibody combo test for the point of care

Project Summary A simple point of care POC diagnostic test with laboratory level performance and the ability to detect the virus across the active phase of infection is vital to efficient prevention and response efforts during the current Zika virus outbreak and future management of the disease as it spreads The ability to differentiate between Zika and Dengue viruses ZIKV DENV is also of utmost importance particularly in low resource settings where Dengue is endemic While lateral flow immunoassays LFIs to detect IgM antibodies are deployable they cannot detect early infection days post onset of symptoms DPO On the other hand the lack of infrastructure and trained lab staff prevents wide use of highly sensitive nucleic acid tests NATs There is a need for a simple POC test that is highly sensitive and can detect infection during the entire period of active infection DPO Daktari proposes to develop a simple POC ZIKV DENV Ag Ab combo test sensitive and specific enough to detect and differentiate Zika and Dengue infections By combining detection of viral antigen with host IgM antibodies we extend the use window of the test to the entire active infection period Non structural NS antigen has been validated as a biomarker for arboviruses and NS antigen tests exist for Dengue their sensitivity however is poor when implemented at the POC No Zika NS Ag tests have been developed to date In this Fast Track program we will adapt Daktariandapos s POC Virus and Protein ViPr platform to detect ZIKV and DENV NS and IgM in blood ViPr consists of Daktariandapos s core technology for automated microfluidic sample preparation load L of fingerprick blood into the cartridge insert cartridge into instrument a high sensitivity immunoassay detection technology based on silver nanoparticle labels and anodic stripping voltammetry proven to enable limits of detection LOD pg mL protein in plasma logs better than LFAs and a simple robust instrument with built in connectivity and a self contained disposable cartridge We will first demonstrate the feasibility of adapting Daktariandapos s viral protein detection assay to the detection of Zika and Dengue antigens Phase I will focus on developing and screening high affinity and specific antibodies against the non structural NS antigens of ZIKV and DENV We will then conjugate selected antibodies to the magnetic and silver particles and we will optimize the assay protocol Finally we will evaluate assay performance in plasma samples In Phase II we will develop the Daktari ViPr IgM assay and then adapt the ViPr cartridge to implement the ZIKV DENV NS and IgM assays We will also upgrade the Daktari instrument to incorporate enough actuators to perform the four parallel assays Finally performance of the integrated test will be evaluated in clinical samples With the simple to use and sensitive Daktari ZIKV DENV Ab Ag combo system it will be possible for health workers with minimal training to diagnose active Zika infection quickly and accurately anywhere in the world Project Narrative A simple point of care POC diagnostic test with laboratory level performance and the ability to detect the virus across the active phase of infection is vital to efficient prevention and response efforts during the current Zika virus outbreak and future management of the disease as it spreads The ability to differentiate between Zika and Dengue viruses ZIKV DENV is also of utmost importance particularly in low resource settings where Dengue is endemic Current technologies are either difficult to deploy widely due to lack of resource and infrastructure or they are deployable but lack in performance We propose to adapt Daktariandapos s ViPr platform to develop a highly sensitive POC ZIKV DENV Ab Ag combo test to aid in the rapid diagnoses of Zika and Dengue infection by health workers worldwide