With summer upon us and visiting area lakes and waterways many of us will undoubtly find things lurking in those waters. One of the most common lurkers that often hitch a ride out of the water with you are leeches. I get all girly at the thought of touching one but what must be done must be done when a child comes to you with an uninvited friend tagging along on their leg. I have found through my own experience that what I was taught was the correct way to remove a leech is actually not the safest way! So leave the salt in the cupboard and read on to find out the safest way to send the uninvited friend home.
Here is what the experts from PBS NOVA have to say. It can be found here.
http://www.pbs.org/wgbh/nova/body/siddall-leeches.html
Q: What is the best way to remove a leech (not being used medically) from the body? Chris Bonneu, Snohomish, Washington Siddall: Dear Chris, I get this question a lot. In fact, I described this in some detail for the "Worst-Case Scenarios: Travel Edition" pocket guide! The problem is not the leech, it's the bacteria in the leech's gut. Leaving aside the fact that salting a leech puts salt in the wound (generally considered a bad idea), or that burning a leech risks burning yourself (also suboptimal), salting, burning, or just plain pulling on a leech risks causing the leech to regurgitate into the wound it is feeding from. Leeches have bacteria growing in their gut. We're not sure why, but Professor Joerg Graf at the University of Connecticut has an incredible research program investigating this symbiosis. What's unusual is not that they have culturable bacteria—even you have bacteria in your gut—but that they have only one! Dr. Graf showed more than a decade ago that the bacterium Aeromonas veronii forms a nearly exclusive relationship with European medicinal leeches, apparently killing or excluding other bacteria. Our collaborative work has since shown that different medicinal leeches from Europe, North America, and Africa harbor just-as-specific symbionts, but of different species. For example, Aeromonas jandei is in Macrobdella decora, the leech you saw in the NOVA scienceNOW segment. So why does this matter? Well, various Aeromonas species are awfully good at living in blood—as you might expect given that's what they're doing in the leech gut—and if they get spit up into the wound, they'll live just fine in your blood. In fact, they have a huge temperature tolerance, growing just fine from fridge temperature to body temperature. Typically, in cases of leech therapy for venous congestion, it's important to give the patient the right antibiotic to prevent accidental infection. Knowing what bacterium is in which species could be critical in knowing what antibiotic is useful, so we're now frantically trying to understand how the diversity of leeches relates to the diversity of microbes. Most infections are local, but there's at least one case of extremely serious meningitis from leech therapy. The same risk comes from removing a leech improperly. Thankfully, there are two proven ways to remove a leech without risk of infection. The first is to relax, watch the leech, and admire its color patterns, and its biology while it finishes its meal. This should take less than half an hour. Thirty minutes well spent contemplating the complexities of life! If you're in a hurry, though, the other method is simply finding the head end and pushing it sideways until it releases the suction. Careful, though: The head end is the smaller end. Most people think the business end of the leech is the fat end, but that sucker is just used for holding on (even Dr. Tyson made this mistake in the NOVA scienceNOW segment). Find the skinny end and use your finger or fingernail to push it sideways off the bite point. Once it's released, you will bleed from the wound. That's okay. The bleeding is normal and is caused by the anticoagulants the leech puts in the wound. Then, just get it to release from the fat end the same way. And for Pete's sake, put it back in the water so it can lead a normal happy leech life!
