Hmmm... lots to think about.
Thank you for your replies, everyone! I am still not sure what I'm going to do... I keep thinking, "What would I put on my children?" (This is hypothetical since I don't have children.) Can a human being get heartworm from being bitten, or do we have certain antibodies that fight off the parasite?
Here's another question... how hard is it to get rid of heartworm once a dog has it? Meg gets tested for it at least 2x/year. Frankly, I'd rather test her for it 6x/year than put her on the medication. If it's caught early enough, it is very treatable, correct?
Am I crazy to think of doing that? Get her blood drawn every 2 months instead of pumping her full of medication...
Then obviously if she was to get them, I'd have to put her on medication to get rid of them, but.... what are the chances she will ever get it?