Cats that are on a macrolide preventative (ie, selamectin,
ivermectin, or moxidectin) can have a false - positive ELISA result after being bitten by an infected mosquito,
with resultant larvae death and no persistent infection.2 Because antibodies are produced after the initial exposure, a positive result
indicates that the cat has been bitten by a D immitis — carrying mosquito 2 to 3 months previously, but not whether it is currently infected.