THE MICROBIOME SUMMIT : Impacts of Sanitizing Our World
Rising Rates of Asthma & Allergies in Children
Dr. Brett Finlay, PhD
The first 100 days of life are critical to a child’s microbiome – and can impact whether they develop asthma or allergies. Dr. Brett Finlay is an advocate of microbial exposure. In this interview, Dr. Finlay will discuss the role that the microbiome plays in childhood asthma and allergies. He will discuss a blockbuster study that he developed, that examined why children who are given antibiotics in their first year of life have higher rates of asthma. From this research, Dr. Finlay discovered four gut microbes that are necessary to prevent the development of asthma.
- Tracey:
- Hi, Brett. Thanks for joining me here today.
- Brett:
- Hi there.
- Tracey:
- You were part of what I consider a blockbuster study that was published in 2015. It really changed the way a lot of people think about the root cause of asthma and allergies. Could you explain to us a bit about your study – what impact you think it’s had.
- Brett:
- Right. So, this is microbiota and asthma and if you were to ask me 10 years ago what bugs in the gut might have to do with asthma, we would say nothing. Maybe I’ll just tell you the story of how this all came about. It’s quite an interesting story. We’d been using antibiotics in most models to change the microbiome to see how they infected with salmonella and e coli because that’s what our lab works on. I was excitedly telling my wife, who is a paediatric infectious diseases doctor, how we’re doing all of this. She looked at me and said, “You know, Brett, kids who are given antibiotics in the first year of life may have higher rates of asthma”. Hmm, that’s interesting. So, being a good husband of course you don’t believe her so you go to the library and, of course, wives are always right and this is true. There were some data indicating that. Then I started to look for studies to prove that microbes actually – gut microbes might actually influence asthma and there weren’t any. There were smoking guns. So, living on a farm versus a city had a decreased rate. Having a dog in the house decreased the rates of asthma. We talk about antibiotics, breast feeding decreased it, C-sections increased it. When we think about that what do all of those things have in common? Well, of course the answer is microbes. And so I convinced a grad student who thought to be working on e coli and salmonella, let’s do some crazy experiments, let’s just take some mice, shift them with antibiotics, microbes, and then test for asthma, with the mouse asthma model. Lo and behold, it worked. It worked beautifully. We found that one antibiotic, Vancomycin, just completely blew away the asthma rates. We’d never seen asthma rates like this is a mouse asthma model. So, that was our first clue that microbes evolved. Also, what we did was we said well when in a mouse’s life does this affect it? It turned out, just really early in life. Very, very early, basically. When you convert that to kids, before the kid is actually weaned from breast feeding. So then, well, okay, that’s mice, it’s interesting, what do you do? So then we hooked up with a child study, it’s called, which is 3,500 kids across Canada looking for asthma. And we started to look at these kids’ feces at three months and one year of age. What we found was that in the three month old kids’ feces, kids that lack these four microbes that we’d found, they basically had very, very high risk of getting asthma later in life. If you had these four microbes, you basically were extremely a low risk of getting asthma. And so that was really interesting but doesn’t prove anything. So, the real experiment to prove it is, we took these four microbes, we took the feces from a three-month old kid that didn’t have them, that we knew actually went on to get asthma later in life, put those four microbes in, or not, put it into a mouse that didn’t have any microbes – they’re called germ-free mice – and then we said, well, can it protect these mice from asthma? When you put those four microbes in you drastically decrease the inflammation in the lungs which is basically asthma. So, putting these four microbes in human feces in a mouse model basically prevented asthma. That was what the study was. That was a big step forward because, you know, we thought microbes might be involved but no one had ever proven it and that’s as close as we could actually do to prove it. So, it was a really exciting study and there certainly have been other studies come out now that have confirmed it which is really nice, as a scientist others are finding this. It’s proven that microbes really are affecting it. Using the mouse studies we were able to show that a lot of this is probably working through the develop of the immune system and early in life these four microbes seem to push it towards allergic asthma type or not and these four microbes seem to prevent it. So, we don’t have all the answers yet but I think it really starts to point the direction you could see in the future. You could take a kid, look at their fecal microbes and say, oh you kind of lack in these things, maybe you should take these certain microbes that will help push you so you’re less at risk for this.
- Tracey:
- So, you know, people are going to want to know, what are these four microbes and where do I get them?
- Brett:
- Yeah, so now there’s a company that’s working on commercializing this, and the idea that you could use it on kids. Another great use, I think, is if the kid had to have antibiotics you could then replenish these microbes to then help them. So, it’s going to, as always in medicine, take forever. You can’t just start shovelling microbes into three-month old kids so we have to start with, you know, healthy young adults and work backwards and isolate them. But it’s coming. If you already have asthma, unfortunately, I think you’re hooped. I think that we’ve shown, we tried in adult mice and it had no effects in an adult. So, this is all part of how you shape your immune system early in life.
- Tracey:
- So, it really just …. like you said, you tried it in the adult mice, no effect, so it’s – there is a critical window where we’re influencing ….
- Brett:
- …. is that when we look at the feces of one-year old kids, so these aren’t young babies, right, there’s no correlation with these four microbes. It was only in three-month olds, so it’s that really, really early window when these kids are just developing their immune systems, one year, really, is too late.
- Tracey:
- Right. So, we’re talking about when you hear in research, you hear in the science, the first 100 days ….
- Brett:
- Yes, and that’s a magic window for all sorts of reasons in this whole microbiome conversation. We know it’s critical in terms of brain development, for example. Obesity, there’s a big window there. Food allergies, et cetera, there’s big windows there. That’s because that’s when this kid comes from what’s basically a sterile environment into the real world and there’s just all these assaults of the world on them and that’s when it really kick starts the whole body developing.
- Tracey:
- Right. So, if I know in my family that there’s a history of asthma, and I wanted to prevent it as best I could and focus on that 100 days, what should be my plan of action?
- Brett:
- We do discuss this in the book. There’s kind of a list of dos and don’ts and I think it’s all related to microbial exposure. Even when you’re pregnant, it’s very important what you eat, in terms of your body, and not asthma but in terms of obesity, for example, if thin mother overeats way too much in the third trimester the kid will inherit those microbes and ironically that will push that kids towards obesity even though the mother was thin to begin with. Because what happens in the third trimester your microbes shift more towards an obese kind of microbe composition and obese microbes are really good at generating energy. So, that’s how you’re feeding your fetus, right? Watch what you’re doing there and then, again, it’s all about microbial exposure. So, we’ve discussed Cesarean section versus vaginal birth. Vaginal birth really decreases it. Breast feeding really decreases it. Having a dog decreases it. It used to be thought you don’t want to have a dog in the house because of allergies. We now know that having a dog in the house will give you about a 20 percent decrease in risk because dogs, they lick the kid, roll with the kid, they’re outside rolling in the dirt. Cat lovers, sorry, there’s no effect either way. Cats just sit in the corner and snub their noses at you. They just do their thing, they don’t really lick the kid so much. So, avoid antibiotics if you can – that causes increased asthma rates. Again, just think of it from the microbial point of view, not just the kid’s point of view in terms of as they develop.
- Tracey:
- Right. Have you seen an impact on clinicians’ practices based on your study?
- Brett:
- Not on clinicians. I think it’s going to take a while because they have to have all the big trials and rightly so. You know, it’s gotto go, you know, double-blind, placebo controlled trial. What we are seeing is a lot is parenting. A lot of parents will say, yeah I was a germophobe. I threw my hand sanitizer out and now I let my kid get dirty. It scared me very much but the kid seemed fine and actually seemed to like it. So, ironically I’ve seen this message is going more, has been going more through the public than I have through the medical profession because, you know, as a physician I can’t say here are some of these, you should test for this and then based on that you should give them these four microbes you could then take home and fix this patient. We’re not there medically yet. So, it’s got to be a higher level conversation about how we raise our children in general and that’s really parents, right? So, I’m targeting parents more so until we get the clinical tools to do it. I do try and tell physicians all the time about antibiotics use and what the consequences are and this whole …. I’ve just been giving grand rounds to a bunch of both pediatrics and child medicine people. They’re flabbergasted that all these microbes might actually be doing. They’re just starting to realize this. But, of course, the question, what I do medically, and so, that’s still coming. It’s early days.
- Tracey:
- I’m very curious. Your wife, she’s a practising pediatrician, what are the main messages that she is giving to her patients. I mean, has she embraced this? Is she a pioneer in her area of medicine?
- Brett:
- Yeah. I mean, I made her read the whole book many times, much to her frustration, because I wanted everything medically correct, right? I don’t want to – everything in this book is based on the science. I can provide studies for everything we say. So, she’s always been a little more flexible realizing it. We had kids. They had ear infections. We would give them prophylactic antibiotics way back when because that’s what you did, type thing. I think it certainly changed her view on antibiotic use and just on child-raising in general and, you know, I think she, too, is telling parents, don’t worry so much about being a germophobe. Your kid will be fine. They have an immune system for the most part. This world is a way safer place than it was 100 years ago for infections and if the kid does eat dirt they’re not going to get smallpox or something from this. You know, it doesn’t exist anymore. So, she’s eased up too and it’s been very fun watching it medically.
- Tracey:
- Thank you very much.
- Brett:
- My pleasure.
