Let's get to the heart of the matter - Heartworm!
Ok, now for those pesky heartworms! Is that really a thing (you type into google)? Hopefully that search lead you here! I admit, I feel like heartworms are old news, especially when new and more impressive parasites are in the news like ticks (https://www.pineridgevet.com/single-post/2019/03/01/Tick-Talk) and fox tapeworms (https://www.wormsandgermsblog.com/articles/diseases/parasites/). The perennial heartworm though seems to remain mysterious to many, and still blog-worthy.