Microbiologist Says To Avoid The Flu, Go Outside

Nov 1, 2013

Want to avoid catching the flu or your co-worker’s cold this year? 

Get some fresh air and wash your hands with soap and water, microbiologist Jack Gilbert tells Here & Now’s Jeremy Hobson.

Gilbert says we’ve created an urban world complete with air conditioning, filtration and windows that don’t open, leading to an environment of homogeneous microbes.

Add a healthy dose of bacteria from the outdoors, and you may just be fine. Getting a dog could help, too.


  • Jack Gilbert, microbiologist at Argonne National Laboratory, and associate professor of ecology and evolution at the University of Chicago.
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And I don't know about you, but I am surrounded by people with colds and flus right now.


I'm so sorry.

HOBSON: It's not just you, Robin. Everybody at HERE AND NOW seems to have a cold or a flu, and maybe that has something to do with the building we work in.

Jack Gilbert is a microbiologist at Argonne National Laboratory and associate professor of ecology and evolution at the University of Chicago. He's with us now. Professor Gilbert, welcome to HERE AND NOW.

JACK GILBERT: Thank you very much. Nice to be here.

HOBSON: Well, I'm in a building that has windows that don't open. Should I be looking to those windows to blame for all the people who have the flu and the cold?

GILBERT: It's a complicated issue. If we take the historical perspective, then yes. I mean, Florence Nightingale, during the Crimean War, was avid about opening windows on wards to improve the quality of her patients. She believed the fresh air was beneficial and would help them to recover. And, indeed, and she saw circumstantial evidence that pointed to that.

And we now have the experimental evidence of recent studies which shows this to actually be true. There are - and if you have windows open in an indoor space, you have less human-associated bacteria. And many of those human-associated bacteria that circulate in the air can be related to pathogens.

HOBSON: Well, in an enclosed space, indoors, how long does it take for the air to circulate in and out? Because if you're only opening up a door now and again to come in and out of the building, where does the new air come from?

GILBERT: The new air comes from air vents that suck air in at the top of the building usually to get it away from the street level and go through a series of very large chambers, which process and condition the air, and then it's pumped out of vents into each room. So what you end up with is heavily processed air that's been already inside the built environment, be it through an air conditioning system or called an HVAC system. And that means that the air has already accumulated a certain je ne sais quoi for the building itself. So you - you're breathing built environment air by the time it reaches you.

But it's interesting you asked how long it takes for the air to circulate. It depends on the size of the building, you know. In our lives here in the Midwest, outside of Chicago, we spend the vast majority of our time indoors, 92 percent. And most of that time is in buildings which we don't open the windows of, even if we can, you know, mainly because it's too hot or too cold. And so we stay inside, and the air inside that building is not re-circulating very often, maybe one house volume every hour.

If you're in Puerto Rico, where we have evidence that buildings are exchanging air more rapidly, the air exchange rate can be the volume of air inside the house 10 or 12 times an hour, significantly different to our buildings here in the U.S.

HOBSON: Well, you have done research on this very topic, looking at the new hospital at the University of Chicago, and you looked at the germs that were there at the very beginning and then the germs that were there 24 hours later. Tell us what you found.

GILBERT: Well, remarkably, you use the word germs. I would say bacteria. There were very few germs actually in the hospital. At the beginning, there was very little of anything. It was incredibly clean. Then as soon as the doctors and patients moved in, you saw this immense increase in diversity. The biodiversity of the bacteria and the fungi increased dramatically.

HOBSON: As soon as they moved in.

GILBERT: As soon, literally within 24 hours. And we see this in other environments, but this was incredibly interesting to us. And more importantly, we're able to track how they move in and what surfaces they colonize.

HOBSON: And I assume that there are no windows that open in this hospital.

GILBERT: There are not but there are ways to significantly improve the diversity of the microflora through just bringing, maybe, therapy dogs into that space. The dogs can have a significant influence upon the microbiome(ph).

HOBSON: So you're saying that the way to get around the fact that our buildings have windows that don't open now is just to bring dogs in.

GILBERT: Well, if you think about it, dogs are conduits to the outdoors. They bring the outdoors indoors. This makes the home look less like a human microbiome, just like the bacteria that live on our skin or in our gastrointestinal tract, but more like a mix between human and wild. And that mix is very important for our health.

HOBSON: So what about those of us who work inside buildings that don't have windows that can open and maybe that can't have dogs at work? What are we supposed to do right now to avoid getting sick?


GILBERT: So it's an interesting question. If you look at airports, more specifically the airplanes that fly in and out of airports, in an airplane you have six exchanges of air throughout the entire aircraft every minute. And that air passes through HEPA filters and extraordinarily fine resolution filters, which even filter out viruses and bacteria. And that means the air is very, very clean. The majority of times when you get sick on an airplane is because you've touched a surface with your hands and picked up something and then put that on your face.

So the best way is probably just to wash your hands. If you know of a colleague who looks a little bit picky, I would say in England, you may want to, A, avoid touching them and, B, try and avoid touching the surfaces they are touching. Or just wash your hands slightly more frequently. I strongly suggest soap and water because other agents can have unintended consequences.

HOBSON: You're talking about super bugs, creating a super bug by using these hand sanitizers and things.

GILBERT: Potentially. I mean, we don't have direct evidence that that is a case. But we do have direct evidence that some hand sanitizers can cause some hormone imbalances in some people. I stress the some of that because it's very preliminary data. I would suggest if you need to use hand sanitizer, just use something with an alcohol base, and that would get rid some of the viruses and pathogens, which may cause a transition.

More importantly, however, go outside more. Take a walk to - have lunch at a restaurant slightly farther away. You'll get fit doing it and you'll also increase your microflora. If you have a healthy microflora on your body, it will or should help to protect you from those bad pathogens your colleagues might be carrying.

HOBSON: Jack Gilbert is a microbiologist at Argonne National Laboratory and an associate professor of ecology and evolution at the University of Chicago. Jack, thanks so much.

GILBERT: Thank you very much.

YOUNG: And again, we're following breaking news. The Los Angeles airport shut down after a shooting around 9:30 local time in Terminal 3. Witnesses say it happened near a security gate. The L.A. Times is reporting that among the wounded are a TSA agent and a suspect. Witnesses also say there was panic in the terminal when the shots began. Reports of people diving for cover, running out on the tarmac. Television pictures have shown police and rescue trucks swarming the airport. People taken out of the terminal in wheelchairs. Local media reports seeing four ambulances driving away. Again, Los Angeles airport shut down after a shooting. This is bound to impact flights across the country.

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