Example of false-positive PCR-nucleic acid lateral flow immunoassay (NALFIA) with a combination of three primer pairs and one DNA template of Ostrea edulis, Crassostrea gigas, and Mytilus edulis. The NALFIA for the negative control shows a light red band for C. gigas although non-DNA template was present and the 3% agarose gel electrophoresis shows no band at the expected position for C. gigas at 174 bp. The NALFIA for O. edulis shows false-positive result for C. gigas and the NALFIA for C. gigas shows a false-positive result for O. edulis, respectively. Likewise, these two false-positive results donńt show an expected band in the gel electrophoresis on lane 6 and lane 7 at 174 bp for C. gigas and on lane 10 at 191 bp for O. edulis, respectively. The NALFIA for M. edulis shows false-positive results for O. edulis and C. gigas, but the gel electrophoresis only shows expected bands for M. edulis on lane 12 and lane 13.