A monoclonal antibody-based Dot-ELISA assay for the rapid detection of animal viruses such as avian influenza virus. The assay includes applying a specimen suspected of containing an animal virus on a porous membrane and treating the specimen with a solution of citric acid or lactic acid and a solution containing a mucolytic agent and a detergent. The treated specimen is then contacted with a primary monoclonal antibody for detecting the virus. If present, the primary moncolonal antibody bind with an antigen of the animal virus specimen. The specimen is contacted with an anti-monoclonal antibody conjugate (secondary antibody) and incubated to facilitate binding of the antigen-bound monoclonal antibody to the conjugate. The bound conjugate and antigen-bound monoclonal antibody is contacted with a coloring reagent to allow visual detection of the presence of the animal virus in the specimen.