During these initial months after infection a female heartworm can produce thousands of larvae a day. (hswaynepets.org)
Animals can not be accurately diagnosed with heartworm for at least six and a half months after infection, he says. (heartwormsociety.org)
Antibodies might be present for several months after infection and then disappear, or be evident for the rest of the animal's life. (dogcare.dailypuppy.com)