A Brief Review
With the terrible fright of the danger of Ebola, the emergence of the unusual Enterovirus 68 causing breathing troubles, and the re-appearance of measles, the idea that we have conquered infectious diseases seems less solid.
Some basics
So it seems like a good time to briefly review one of our two great success stories in creating a world in which we can feel safe from harm from infections. Those two great defenses are immunizations and antibiotics.
The word antibiotic literally means, against life, but really refers to chemicals that kill bacteria but not us. There are 4 forms of life that infect us: Bacteria, virus (e.g., colds, flus, measles, chickenpox, Ebola), parasites (e.g., giardia, worms), and fungi (e.g., ringworm, yeast infections). Antibiotics only kill bacteria. There are some medications that kill a very few viruses, such as acyclovir for herpes, but these are called anti-virals. And there are many drugs that kill parasites and fungi, but these are called anti-fungals and anti-parasitic drugs.
That leaves drugs for bacteria, the antibiotics. Of all the drugs that kill the various germs, antibiotics have been the most remarkable in their ability to kill the germ, but not harm the person (more on that below).
They have this rather strong safety record because bacteria have many different chemistries than animal cells. So a drug could stop a bacterial chemical reaction without interfering with ours.
Resistance
But this is the first problem with antibiotics, they attack a living cell, the bacteria. And all life tends to find a way to adapt. Bacteria adapt by mutating and reproducing rapidly. Bacteria divide so rapidly that one can become millions in a relatively short period of time. Add in the ability to mutate, and a one in 10 million change can appear in a short time. If that change alters a chemical reaction that the antibiotic for that bacteria blocks, the antibiotic will no longer harm the bacteria- this is what is meant by resistance.
Keep in mind that if one person takes a course of one antibiotic, it is very, very unlikely a new bacteria no longer affected by that antibiotic will appear. Resistance is almost always the result of millions of doses of antibiotics across a population.
But we do see this happening when millions of animals are given antibiotics every day. Or when people are given antibiotics for common viral problems that antibiotics, exposing millions of people and their bacteria to antibiotics for no actual benefit (remember, antibiotics do nothing to viruses).
Harm from antibiotics
Compared to most cures for other diseases, antibiotics are pretty gentle. Think of surgery and chemotherapy as the main curative interventions, and you can see 10 days of an antibiotic often has no or few side effects compared to other cures.
But, there are three ways antibiotics can cause serious trouble:
This last point leads to two imperatives:
Some basics
So it seems like a good time to briefly review one of our two great success stories in creating a world in which we can feel safe from harm from infections. Those two great defenses are immunizations and antibiotics.
The word antibiotic literally means, against life, but really refers to chemicals that kill bacteria but not us. There are 4 forms of life that infect us: Bacteria, virus (e.g., colds, flus, measles, chickenpox, Ebola), parasites (e.g., giardia, worms), and fungi (e.g., ringworm, yeast infections). Antibiotics only kill bacteria. There are some medications that kill a very few viruses, such as acyclovir for herpes, but these are called anti-virals. And there are many drugs that kill parasites and fungi, but these are called anti-fungals and anti-parasitic drugs.
That leaves drugs for bacteria, the antibiotics. Of all the drugs that kill the various germs, antibiotics have been the most remarkable in their ability to kill the germ, but not harm the person (more on that below).
They have this rather strong safety record because bacteria have many different chemistries than animal cells. So a drug could stop a bacterial chemical reaction without interfering with ours.
Resistance
But this is the first problem with antibiotics, they attack a living cell, the bacteria. And all life tends to find a way to adapt. Bacteria adapt by mutating and reproducing rapidly. Bacteria divide so rapidly that one can become millions in a relatively short period of time. Add in the ability to mutate, and a one in 10 million change can appear in a short time. If that change alters a chemical reaction that the antibiotic for that bacteria blocks, the antibiotic will no longer harm the bacteria- this is what is meant by resistance.
Keep in mind that if one person takes a course of one antibiotic, it is very, very unlikely a new bacteria no longer affected by that antibiotic will appear. Resistance is almost always the result of millions of doses of antibiotics across a population.
But we do see this happening when millions of animals are given antibiotics every day. Or when people are given antibiotics for common viral problems that antibiotics, exposing millions of people and their bacteria to antibiotics for no actual benefit (remember, antibiotics do nothing to viruses).
Harm from antibiotics
Compared to most cures for other diseases, antibiotics are pretty gentle. Think of surgery and chemotherapy as the main curative interventions, and you can see 10 days of an antibiotic often has no or few side effects compared to other cures.
But, there are three ways antibiotics can cause serious trouble:
- Allergic reactions. Antibiotics can allergic reactions more than most drugs. Usually the reactions are mild, mainly an itchy rash, but sometimes the reactions can be very severe, even dangerous. In the case of penicillin, it is estimated that the most severe reaction, a deadly anaphylaxis, occurs 1 in every 100,000 doses!
- Discomfort. Antibiotics are associated with stomach ache, changes in stooling, headache, and other discomforts.
- Changes in your natural bacterial environment. This is potentially the most worrisome side of using antibiotics. They kill bacteria, which is incredibly important when it comes to curing dangerous bacterial infections, but they kill not just your infection, but your normal bacterial populations, especially in your gut. It turns out our guts require healthy thriving bacteria in order to work well. Without them, inflammations of the gut with diarrhea and abdominal pain, can begin to appear. This is the power of probiotics, to replenish diminished normal gut bacteria after a course of antibiotics.
Bottom Lines
1. Antibiotics are the drugs that kill bacteria and should be used to cure significant bacterial infections. They have no power over or impact on viruses- that's why they don't help anyone with a cold.
2. Resistance is not seen with one course of antibiotics in one person, not even in several, but rather from millions of doses across large populations.
3. Use of antibiotics is safe, but comes with some risks, so they should never be used for situations they will not work (like viral infections), and only when curing the bacterial infection is important.
One last point, it is very hard for science to find or create new antibiotics. Most development efforts by drug companies fail to create new antibiotics, and they do not generate big sales as people take them for a week or two, not every day like a cholesterol lowering drug.
As a result of both facts, nearly all pharmaceutical companies have stopped trying to create new antibiotics. As resistance to our known antibiotics grows, an inevitable result of evolution, we may find ourselves in a time when no available antibiotics will work, which would be a rather horrible development.
This last point leads to two imperatives:
1. We must all be careful not to use antibiotics for viral infections, such a practice leads to the millions of extra doses that breeds resistance.
2. We must find a way to make the creation of new antibiotics a viable pursuit, or no matter what we do, the ones we have will one day no longer work.
To your health,
Dr. Arthur Lavin
*Disclaimer* The comments contained in this electronic source of information do not constitute and are not designed to imply that they constitute any form of individual medical advice. The information provided is purely for informational purposes only and not relevant to any person's particular medical condition or situation. If you have any medical concerns about yourself or your family please contact your physician immediately. In order to provide our patients the best uninfluenced information that science has to offer,we do not accept samples of drugs, advertising tchotchkes, money, food, or any item from outside vendors.
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