Performance of a microfluidic immunofluorescence assay kit for equine influenza virus antigen detection.

This study examines the effectiveness of a microfluidic immunofluorescence assay kit in detecting the Equine Influenza Virus (EIV). Scientists found that the kit was 60.7% accurate in recognizing EIV in infected horses, exhibited a high specificity for EIV antigens, and performed comparably to other rapid antigen detection kits.

Microfluidic Immunofluorescence Assay Kit for EIV Detection

• This research focuses on the microfluidic immunofluorescence assay kit that usually identifies influenza virus and SARS-CoV-2 antigens in human specimens, investigating its competence to detect Equine Influenza Virus (EIV).
• EIV infection is a significant respiratory disease affecting the global equine industry. Quick diagnosis is imminent to control disease outbreaks, making the point-of-care testing facilitated by this kit substantial.
• Using human specimen detection procedure, the kit demonstrated the capability of identifying 11 EIV strains. These strains were realized within a 12 minute turnaround time, indicating the kit’s rapid response in EIV identification.

Analyzing Kit’s Effectiveness in Horses

• Applying the assay kit on nasopharyngeal swab samples from three horses experimentally infected with EIV, it displayed a sensitivity of 60.7%. This testing was referenced to a real-time reverse transcription polymerase chain reaction, a standard assay for evaluating infectious diseases.
• The kit’s sensitivity was compared with two other rapid antigen detection kits – one based on immunochromatography and the other on silver amplification immunochromatography. The microfluidic immunofluorescence assay kit exhibited higher sensitivity than the immunochromatography kit (53.6%) and matched the sensitivity of the silver amplification immunochromatography kit (60.7%).

Kit’s Specificity for EIV Antigens

• In addition to sensitivity, the study examined the specificity of the kit for EIV antigens. It failed to detect nine non-EIV viruses, including an equine coronavirus strain and seven types of bacteria.
• This inability to recognise non-EIV pathogens indicates that the kit possesses high specificity for EIV antigens, reducing the probability of identifying false positives in EIV detection.

Overall Assessment of the Kit

• Considering the kit’s sensitivity, rapid turnaround time, and high specificity, it could be an effective diagnostic tool in the field.
• Though it performs similarly as other rapid antigen detection kits, it offers additional benefits such as being able to detect multiple EIV strains and having minimised false positives.