Answer: That is not ideal - if s / he is positive, especially with a heavy load, it can cause a massive die -
off of microfilaria / worms and be very detrimental to his / her health.
However, starting prevention without testing can be harmful, because once the heartworms reach a certain point in development, the killing
off of the microfilaria in combination with juvenile or adult heartworm in the system can be damaging to your dog's cardiovascular system.
Not exact matches
When the mosquito takes a blood meal
off of one
of these animals, it picks up the
microfilaria along with the blood.