Using IgY for diagnosis of respiratory infections: practical application in COVID-19.

AIM: The COVID-19 pandemic underscores the need for expanded diagnostic tools to combat respiratory pathogens with pandemic potential, particularly in developing countries. This study aimed to create a Dot Blotting test utilizing IgY antibodies for acute respiratory infection diagnosis, with COVID-19 as the disease model. METHODS: Leghorn chickens were immunized with precipitated SARS-CoV-2 virus, and IgY antibodies were purified via ammonium sulfate precipitation and titrated by ELISA. Dot Blotting detected viral antigens in saliva samples, demonstrating efficacy comparable to ELISA tests. RESULTS: The IgY antibody was successfully produced and purified, obtaining a titration of 1:16,000. The ability of IgY to detect SARS-CoV-2 in clinical saliva samples showed promising results in terms of accuracy (91.3%), sensitivity (92.5%), specificity (90.0%), positive predictive value (PPV) (90.2%), negative predictive value (NPV) (92.3%), and Cohen's Kappa (0.825). CONCLUSION: Chicken antibodies proved effective for early and accurate diagnosis of respiratory infections, including COVID-19. This study validates the efficacy of chicken antibodies in diagnosing respiratory infections, supporting pandemic response in developing nations. Expanding diagnostic capabilities is crucial for combating respiratory pathogens.