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Protect Yourself from Hantavirus

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Protect Yourself from Hantavirus

Apr 07, 2017

Spring is here and it’s time to start that spring cleaning. But if you come across mouse droppings you could be exposed to hantavirus. Emergency room physician Dr. Troy Madsen discuss the virus and simple cleaning steps you can take if you find mouse droppings.

Episode Transcript

Interviewer: Doing some spring cleaning and you come across some mouse droppings? Well, stop and listen to this podcast first before you do any more cleaning. That's next on The Scope.

Announcer: Health tips, medical news, research, and more for a happier, healthier life. From University of Utah Health Sciences, this is The Scope.

Interviewer: If you're doing some spring cleaning, maybe cleaning out the garage or an old attic, and you see some mouse or some sort of droppings, is that a concern? It turns out yes, it is, and there's a procedure you should go through if you do see that before you continue cleaning. Dr. Troy Madsen is an emergency room physician at University of Utah Health. What's the main concern here?

Dr. Madsen: The big concern here is something called hantavirus. This is a virus that mice carry. It's actually endemic to the four corners region, so southeastern Utah, but we've certainly seen cases in Salt Lake. There was a big outbreak of this virus at Yosemite several years ago. This is a virus that mice carry in their urine.

So the way people catch this virus is they're cleaning mouse droppings, they see some droppings, they sweep it up, sweep it into a dust pan. As they're sweeping, usually, where there are mouse droppings, there's also mouse urine, it aerosolizes this urine, this dry urine, kind of kicks it up into the air, they breathe it into their lungs, and then it can cause an extremely severe lung infection.

Very fatal, at least half of people who get this infection die from it. It's a bad thing to have. I personally know someone who had it who was cleaning his garage, caught the virus after cleaning. It's a big concern. Then you may ask, "Why is it a big concern this year in particular?" Because it's been a very, very wet winter, and when we have wet winters, the rodent population explodes.

This is exactly what happened at Yosemite several years ago when there was a big outbreak there. You get more mice around carrying this virus, more potential for exposure for humans, so we could potentially see cases of these.

Interviewer: If you see mouse droppings, that's the first hint that you need to do what we're about to talk about, is what do you about it, because you want to clean that mess up.

Dr. Madsen: Exactly. You're not just going to leave the mouse droppings. You've got to do something about it. Take some water, pour some bleach in it. It's kind of a 1 to 10 ratio. If you have a bucket of water, just get some bleach in that. You can then use that water and bleach in a spray bottle or pour it on the mouse droppings some way where you're getting the bleach on there, getting that area wet.

The reason this works is because you've got the bleach on there that's killing the virus. Then you've also got something wet on there. So when you wipe that up, it's not creating an aerosol. It's not creating something out of that dry urine that it gets in the air and you breathe in your lungs. That's the biggest thing for prevention.

Interviewer: So then you just target where you see the mouse droppings. You don't have to spray the solution on every surface in wherever you happen to be working?

Dr. Madsen: Exactly. If you're cleaning a garage, you figure if you're trying to get this solution all over, it's just not practical. Usually, where the mice have their droppings, that's where the urine is. My recommendation would be to have a spray bottle with you with the solution in it. If you're cleaning the garage, spray five or six squirts on that area. Let it sit for 5 to 10 minutes, then wipe it up, and you should be good at that point.

Interviewer: Okay, and wear a mask at the same time?

Dr. Madsen: Absolutely.

Interviewer: Would a mask alone stop it?

Dr. Madsen: Great question. I don't have a great answer. I think a mask would definitely help, would probably prevent it. I would still take the precautions with the solution though.

Interviewer: Let's say somebody didn't catch this in time, and now they're concerned that they have hantavirus. What are the symptoms?

Dr. Madsen: It's a little bit of a challenge because it probably feels at first like a bad cold, but then it progresses very rapidly to where you're having very significant difficulty breathing. It's one of those things where if you really have it, you'll probably know you have it, and you'll probably know pretty quickly.

Interviewer: A cold following some sort of a cleaning job in a place where this could have happened would be your first hint, and then go to the ER?

Dr. Madsen: Exactly. I would go to the ER for this. I don't want you to rush to the ER if you've been cleaning and then you get a little bit . . . some sniffles, but it's one of those things where it's something you would go to the ER for, anyway, because you would feel so sick and have so much trouble breathing. Even if you hadn't been cleaning, you would say, "Something's not right here."

Interviewer: Then what do you do to treat it?

Dr. Madsen: That's the challenge with it. Really, the treatment for it in the hospital is supportive care. We're helping people get through it while, hopefully, their body fights this off. Often, that means breathing for them, putting a tube in, and putting them on a ventilator to get them through this. In severe cases, that's what we have to do, but it's a challenge to treat.

Interviewer: So well worth avoiding?

Dr. Madsen: Absolutely. Try to avoid it.

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