Biofilms and screaming children

The good Dr. Flea has taken some flack previously for comments he's made regarding the treatment of ear infections (or rather, the non-treatment of such). As he notes, most ear infections resolve without antibiotics. Despite this, ear infections are the most common illness for which children visit a pediatrician, receive antibiotics, and undergo surgery in the U.S., at a huge economic cost. A new paper in the Journal of the American Medical Association suggests at least some of that cost is wasted, because the bacteria are present in the form of antibiotic-resistant biofilms.

A biofilm is, essentially, a mat of bacteria and extracellular goo that holds it together. They are everywhere: in your sink, your shower, your pond, and your body. (Dental plaque is actually a type of biofilm, consisting of dozens of different species of bacteria). Biofilms have gained the attention of scientists and medical professionals, however, largely because of their formation on in-dwelling medical devices such as catheters and heart valves. Bacteria growing in this form are specialized, and resistant to antibiotic treatment due several factors. First, the physical protection afforded to them by the extracellular matrix (the "goo" made up of polysaccharides), which makes diffusion of the antibiotic into the biofilm matrix more difficult; and second, the fact that many bacteria grow much slower in a biofilm than they do in their free-living ("planktonic") state. Since most antibiotics target bacteria which are actively growing, this retarded growth therefore serves to protect them. In fact, bacteria growing in a biofilm can be as much as 100 times more resistant to antibiotics than identical bacteria grown in a planktonic form.

How does this relate to ear infection? It was previously known that a species of bacteria that frequently causes otitis media in children--Haemophilus influenzae--could form a biofilm in a chinchilla model of otitis media. In this new study, they obtained biopsies from children preparing to undergo either a tympanostomy tube placement in order to reduce chronic ear infections (the study group) or cochlear implantation (the control group). When they examined the samples, they found that not only Haemophilus, but also other common pathogens of otitis media (Streptococcus pneumoniae and Moraxella catarrhalis) do indeed form biofilms within the middle ear of infected children. Overall, biofilms of some type were found in 92% (46/50) of the patients with otitis media, and were not found in the control samples (but this is a big limitation, because only 8 control samples were used).

When my son was young, he had chronic ear infections. I know how incredibly difficult they can be for both the parent and the child. I can't even recall how many times he was put on antibiotics, only to be in pain with a recurrent infection (and lots of lost sleep between the two of us) 6 weeks later. We had considered tubes or long-term administration of antibiotics, and were waiting for one more recurrence to decide--which never happened. This new paper makes a lot of sense from years of clinical observation (and that of many sleep-deprived parents and kids), but it doesn't give a lot of comfort when a child is up and screaming at 2AM that their ear hurts (or worse, can't tell you exactly what's wrong) and you just want to give them something, anything, to make it better. There is, however, a bit of light, as there is the possibility of designing drugs that block a bacterium's ability to form a biofilm in the first place. If this formation were prevented, antibiotics could be employed (theoretically, with a higher success rate), or perhaps the body's own defenses could better resolve the infection without any further intervention. Either way, as one of the study's authors opined, "We need to start thinking about ear infection in a different way."


Hall-Stoodley et al. 2006. Direct Detection of Bacterial Biofilms on the Middle-Ear Mucosa of Children With Chronic Otitis Media. JAMA. 296:202-11.

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Doc Flea wrote:

Here's the bottom line folks: Most ear complaints do not require the attention of a physician. They certainly do not merit visits to the emergency room! An "ear" is not an emergency.

Doc Flea has more common sense in his little pinky than the collective scientists on this blog!

You rock, Flea!

Hank Barnes

By Hank Barnes (not verified) on 12 Jul 2006 #permalink

I got ear infections once or twice a year into my late teens. I recall once when my folks weren't home, and the school sent me to a neighbor's home. My friend's mom got out an electric heat pad, and had me lie my head on it, ear down. In half an hour, lots of goop (that's a technical term) dribbled out of my ear, and things got better. I never had an ear infection for more than a day. They were painful, no doubt about that. I don't recall getting antibiotics for them, ever. The last one was probably around 1975.

What i don't understand is why i don't get them still. It's been maybe thirty years without a single event. Any ideas? Could i have developed resistance to all 19 infectious agents? Seems unlikely.

The reason why children are more likley to get ear infections that adults is just pure physiology. The eustachian tubes, which connect the inner ear and the throat, is much storter and thereby much easier for bacteria to traverse. Bacteria gets in the middle ear, the eustachian tubes become swollen and blocked, and the infection worsens. Ear infections are common durnig childhood, and are usually outgrown, but I think its terrible advice to say they should be ignored. Removing the adenoids or tonsils, where much of the bacteria breeds initially, is a much better course of action than "tubes in the ears," IMHO. An unattended ear infection can cause deafness, in fact. Not that this means antibiotics--Sudafed can often do the trick, as pseudoephedrine lessens the swelling in the tubes. Check out the National Institute for Deafness and Communication Disorders page on otitis here:

Not only do you have a screaming toddler who doesn't know what's wrong, but there are often other symptoms of bacterial infection such as thick green nasal mucus. There can even be eye discharge like you'd see on a sick dog. My experience has been that once we got the doctor's appointment (agreed: this is not for the emergency room), got the diagnosis, and got the antibiotics, everything cleared up in a day or two, after which I was always careful to keep using the full course of antibiotics.

I realize that before antibiotics were common you could safely let it run its course, but there are some clear advantages to fixing it up fast. The kid is more comfortable, and if you have to bring them to daycare, it's a relief not to have to explain away the thick green nasal mucus and insist that nothing serious is wrong.

So I'm divided. I agree that antibiotics are overused and do feel bad about this, but I can also understand why people want them.

I remember getting frequent ear infctions after moving to Wisconsin from New Mexico. After a couple of years of frequent infections the Doc,
suggested tring an old "home remedy": put a single drop of vinegar in the ear. This should
change the PH, making your ear incompatable with baterial growth.
Amazingly it worked, and I got no more infections after that.
I have to wonder if some simple low tech tricks, might exist that could
clear up many of these problems.

The color of snot is meaningless. Many viral infections cause thick green drainage and many bacterial cause clear drainage.

T Hewitt,

There is no evidence that vinegar or any other home remedies impact the incidence of otitis media(inner ear infections) which is what we are discussing. I don't know of any for otitis externa(swimmer's ear) but I can't say for sure. Your ear drum would have prevented the vinegar from reaching the area of infection which is a good thing as that would have likely hurt like hell. There are some simple low tech tricks to prevent ear infections in children though. Don't smoke around them and don't put them to bed with a bottle.

When I was young, I would get horrible earaches which were probably swimmer's ear. My parents would treat it in two ways: having me lay my ear on a hot wet washcloth, and they would blow cigarette smoke in my ear. I'm fairly certain this was the worst possible thing to do, and I wonder where they got this idea? I've never heard anyone else mention it. I still avoid swimming without earplugs.

What about exercise? The mammallian ear is rather close to the jaw, thanks to evolutionary development. Giving the child something tough to chew on would exercise the joint and associated structures. This exercise serving to break up biofilms and associated plugs.

Anybody looking into that?

I gotta reply to Shelly Batts, I have not suggested anywhere in my writings that AOM should be ignored. Have you been reading your Flea?

Do you need to go to the doctor's office to use OTC meds? At least you can call me on the phone, or email me, if you need help with the dosing.

Hank, thanks for the kind words, man, after the f***ing week I've had I owe you a beer.


I've suspected for some time that repeated exposure to antibiotics favors development of chronic OM. Biofilms provide some explanatory power. Thanks for the link. I'm gonna check it out.



Clark Bartram:

The color of snot is meaningless. Many viral infections cause thick green drainage and many bacterial cause clear drainage.

Regardless, it's pretty embarrassing to have to bring a kid to daycare whose nose is running with thick, opaque snot of any color. I realize that embarrassment is not a medical emergency, but when you have to deal with people on a regular basis and entrust them to care for your kids, it's very difficult to look like a responsible parent while engaging in very non-conformist behavior with respect to antibiotic use--even if that non-conformism is backed by the best science. (BTW, the kids have not had frequent ear infections; we do not smoke, and as far as I know do our best to prevent these things from happening.)

In the few occasions in which the doctor prescribed antibiotics, this symptom and related ones went away fast. That's not a controlled experiment, so it may have been a viral infection after all and this may have been a coincidence. My doctor and I may be antibiotic abusers. My only point was that there is potentially some social pressure involved to not simply letting an illness run its course. Surely I'm not the only one who experienced this?

Note: the obvious solution would be to keep your kids out of daycare. This is fine if we're talking about a day or two as necessary. If we're talking about an illness that goes away by itself but takes a week, this is a problem when both parents work. If there is a way to quicken recovery and take fewer child-care sick days, then I prefer to save the sick days in case there is an illness lasting a week or more that cannot be cured any faster. I can understand if somebody disapproves of this attitude, but I'm simply reporting what is probably a very common tradeoff.

The problem lies in the absurd "no snot" policies of many daycare centers as well as their irrational fear of fever. And often their definition of fever is 99 degrees or higher which is not based on medical reality. My daughter is in daycare fulltime so I know full well what it is like to deal with these necessary evils.

If you were to take a random sampling of 10 kids off the street, all showing no signs of viral illness, half would grow a virus of some kind. It is silly to make a child stay home for snot or for a fever if the child is doing well. If a child is acting sick, vomiting, having diarrhea, etc, then they should stay home.

My personal favorite are the daycare rules about pink eye. They kick a child out until either their eyes are clear or they are being treated. By far viral pink eye is more common so pediatricians are pressured to put a child on eye goop so that the happy smiling kid with a mildly irritated eye can go to daycare.