With all these cups lying around, it’s cups difficult to tell whose is whose. The adults at the volleyball picnic tried, with varying degrees of success, to keep track of which was their cup, but many of the youngest children just grabbed for whichever one was closest. That, of course, worried their parents who were just sure that everybody else had some kind of horrible disease that their child would get, merely by drinking out of the wrong cup. Then too, in the in-between-games rush to get a quick drink of water, probably quite a few of the volleyball players accidentally grabbed the wrong cup, not to mention a few flies, ants, and spiders checking out the cups while the humans weren’t looking.

Immune System

advertizing slogans Advertizing agencies have convinced many people in our present-day society that all bacteria are terribly dangerous and something to be avoided at all cost. Antibacterial agents are needlessly added to all kinds of products and promoted as “selling points” for those products. Not only are we bombarded with a glut of antibacterial dish detergents and body “soaps,” but they’re also trying to sell us a variety of other products such as mattress pads and children’s nightwear embedded with antimicrobial agents, pet bowls and bath mats made from plastic which has antimicrobial agents embedded in it, and the ubiquitous hand sanitizers.

In addition, restaurants and grocery stores are required to use huge amounts of various antibacterial agents as disinfectants. Our hospitals and other health care facilities are over-using antibiotics and antiseptics, while quite a number of doctors, unhesitatingly, write prescriptions for antibiotics for people suffering from viral infections such as the common cold. Even places like movie theaters and schools feel that they must disinfect every reachable surface.

What’s the result of all this? Many people have been led to believe that all this over-use of antibacterial agents is due to the presence of larger numbers of more deadly bacteria, when in fact, quite the opposite is true: the over-use of antibacterial agents is the cause of the “problem,” and many of those “deadly” bacteria are so labeled because they are now resistant to all of the commonly over-used antibacterial agents. Multiple drug-resistant Staphylococcus aureus (MRSA) is a huge problem in many hospitals.

Here’s an explanation of what’s really going on. First, look at the people around you, and notice how different they all are from each other. Think not just about looks, but about how their bodies function: someone might have lactose intolerance, another might have childhood diabetes, and yet another might have hemophilia, all of which are genetic conditions. Similarly, in any population of the same species of bacteria, there is just as much genetic variation, with the result that some of the bacteria will just naturally be more susceptible to the effects of some of our antibacterial agents while others, because of their genetic code and resulting metabolism, will be resistant or immune to the effects of a particular chemical (From what I’ve heard, some bacteria can even use tetracycline as food!).

effects of antibiotics Ecologists talk about something they call “natural selection,” by which they mean that when a population of the same species of organism is subjected to some “environmental pressure” – often things like availability of food, homes/protection, or other resources, those individual organisms which are best suited, genetically, to cope with those conditions will survive and live to reproduce, while those which, genetically, cannot cope with the existing environmental conditions will die and their genes will not be passed on. That is exactly what’s going on here. The bacteria which are susceptible to a particular antibiotic will die when exposed to it, while the bacteria which have slightly different metabolic processes, and thus are resistant, will live. Not only will they live, but within just a few hours, they will have grown enough to divide and make more just like themselves. Soon, the population will be “rebuilt,” but now, all the individuals that make up that population will be resistant to that chemical, and the next time it is applied to those bacteria, it will have no effect on them.

Now, if we’re talking about something like an occasional course of an antibiotic for some short-term, critical need, such as fighting a strep throat infection, the idea is that the drug knocks the population down to a low-enough level that the person’s immune system can attack the remaining bacteria, and few, if any, live to reproduce. Then, if that person would happen to get strep throat, again, several years later, chances are that the new infection is caused by new bacteria from “outside” and probably not the descendants of those which survived the first time. Thus, the same antibiotic can be used again, with equal success. However, when all the bacteria in a person’s body and/or local environment are exposed to lower levels of one or several chemicals on an ongoing basis, those bacteria will become resistant or immune to that/those chemical(s). . . and then newer, “stronger” (= more dangerous to humans) chemicals are developed/used, and the bacteria evolve to become resistant to them, too. Soon, the surviving bacteria that have been “selected for” (remember natural selection?) have such complicated and varied metabolic processes that they can deal with, detoxify, eat, or otherwise live-in-spite-of just about any new chemical that’s thrown at them.

All of this “bacteria-phobia” shows a complete lack of understanding of how our immune systems work, and as we’re increasingly seeing, actually interferes with the proper “development” and functioning of people’s immune systems. The immune system needs exposure to “invaders” so it can “learn” to fight them — no prior exposure = no ability to fight off a disease organism. Many people these days are keeping their local environment too “clean.”

All those natural, protective chemicals in our skin and scalp and on our hair are part of our body’s way of fighting invaders. Those non-specific defense mechanisms (not specific to a particular invader), along with others such as fever, are out body’s first response to foreign invaders, and these work side-by-side with the specific defense mechanisms (things that target and fight certain, specific invaders) such as the antibodies produced by our immune systems. We have these kinds of non-specific, protective chemicals in other places in our bodies, too, including, for example, within our stomaches. To stimulate development of both the non-specific and the specific defense mechanisms – for a healthy immune system – to a reasonable extent, children are supposed to play in the dirt and put bugs and stuff in their mouths! When my niece was a baby, my brother told me she frequently crawled over to the sliding glass door, where she would pick dead insects out of the door track and, before they could stop her, put them into her mouth. With few major childhood diseases in between, she is now a young adult. However, there does, obviously, need to be a reasonable “balance” — babies and toddlers need to be exposed to enough potential-invaders to develop healthy immune systems, but not exposed to so much at once, beyond what their immature immune systems can handle, so that they get really sick, instead.

Over-use of antibiotics can also cause other problems. For example, if a person’s body is repeatedly exposed to a particular antibiotic (like penicillin), that person’s immune system may come to recognize that chemical as a “foreign invader” and begin producing antibodies, histamines, and other protective chemicals to fight that perceived invader. This kind of inappropriate over-reaction, whether to antibiotics, food items, or other substances in a person’s environment, is called an allergy. Once a person develops an allergy to a particular antibiotic, if in the future that antibiotic is needed to treat a certain condition, it cannot be used in/on that person due to the possibility that the person’s immune system might overreact to the antibiotic, possibly even causing the person to go into anaphylactic shock.
Prescribing/taking antibiotics for a viral infection such as the common cold is a waste of time and money as well as selecting for resistant bacteria and increasing the chances of an allergic reaction to that drug. Antibiotics target/inhibit certain body processes within certain types of bacterial cells. For example, penicillin specifically/only inhibits formation of a chemical called peptidoglycan which some bacteria (called “Gram+”) need to form their cell walls, while tetracycline, streptomycin, and Zithromax® (azithromycin) specifically/only interfere with bacterial ribosomes’ ability to synthesize the proteins needed by the bacteria. Viruses are not alive, do not have cells, much less cell walls or ribosomes, and do not carry on any kinds of chemical processes, thus are not affected by antibiotics. If a person has a sore throat, appropriate testing should always be done, first, to diagnose whether the person has strep throat (which is treatable by antibiotics) or a viral infection (which is not). If a person has bronchitis, coughing, etc., diagnosis should first be done to determine whether the person has something like bacterial pneumonia (treatable by antibiotics) or a viral infection (cold or flu, not treatable by antibiotics).

As just mentioned, small children’s immature immune systems need to gradually be exposed to “every-day” things so that those immune systems will mature and develop properly. On the other hand, we’re increasingly seeing/recognizing problems associated with our all-too-common practice of overwhelming those little immune systems by “throwing too much at them” too early, before they’re mature- and developed-enough to handle it.
cow Once upon a time, back in the days when cows were milked by hand and smallpox was still a common disease, a man by the name of Edward Jenner noticed that milkmaids frequently caught a similar but much, much more mild disease, called cowpox, from the cows that they milked. Jenner also noticed that milkmaids didn’t get smallpox. From this, he developed the hypothesis that having and recovering from cowpox gave a person immunity to the much more serious disease, smallpox. To test his hypothesis (this kind of testing would certainly NOT be allowed now!!!), first, he purposely inoculated a boy with body secretions containing the cowpox virus, and of course the boy got cowpox. When the boy had recovered from that, Jenner purposely inoculated the boy with body secretions from someone who had smallpox – he was so convinced that his idea was right that he purposely tried to make the boy sick with a deadly disease! Luckily for both of them (and for the rest of us) Jenner was right. Since the cowpox virus came from a cow, the Latin term vaccin, which means “of a cow” was used to describe Jenner’s process of giving people cowpox to prevent smallpox, hence the origin of the words “vaccine” and “vaccination.”
A vaccine is/contains a weakened or inactivated form of some particular virus. This is given to a person (vaccination) to stimulate his/her immune system to fight off that “wimpy” form of the virus so when the real thing comes along, the person’s immune system will already know how to fight it. Because a person’s immune system isn’t able to fight an invader without prior exposure, vaccination will often/usually cause mild symptoms of that disease. For example, smallpox vaccinations always cause one “pock” at the site of inoculation, and just about everyone who has been vaccinated for smallpox has a “smallpox scar”. Pregnant women who have never had German measles (or the vaccine for it) are told to stay away from children who have recently been vaccinated for that, because some of the virus in the child’s body (from the vaccination) could be transferred to the pregnant woman and cause birth defects. Many vaccinations cause fever and/or mild flu-like symptoms. Thus, vaccinations are not totally “safe” – they do contain potentially “bad” viruses.
When I was a child, young children (not practically-newborn babies) were given a smallpox vaccination, and school-age children were given polio vaccine. Beyond that, there were not vaccines available for the “common” childhood diseases such as measles, mumps, and chickenpox. Children just “got” those diseases when exposed to them, were sick for a short while, then recovered and were immune to the diseases. Now, vaccines have been developed for all of those childhood diseases, and school systems try to tell parents they “have to” have their children vaccinated. Several of the other Biology faculty here at Clermont – people who teach our Microbiology course – have shared with me that they have chosen to not have their children vaccinated. One faculty member mentioned to me that she has prepared a written statement explaining her position, which she presents to each of her children’s schools that wants to see vaccination records, and that so far, the schools have been good about putting that piece of paper on file and not hassling her about it.
Why would anyone want to not vaccinate a child? Many people are increasingly skeptical about the way in which it is done. Mostly for the convenience of the doctor, increasingly, vaccines for several viruses are mixed together in one shot. Thus a young, immature immune system is purposely exposed to several “bad” viruses simultaneously, so that rather than having the time to work on developing an immunity to each one, individually, the child’s immune system is over-stressed by trying to cope with all those viruses at one time. To make matters worse, the age at which that big dose of mixed viruses is presented has been pushed back earlier and earlier. Many vaccines which used to be given at 1 year or maybe 6 mo. are now given within a week or two of birth. A newborn baby’s immune system is too immature to handle that load! Either the baby might get very sick from not being able to fight off all those viruses and/or because the baby’s immune system is so immature at that point, it may not be developed enough to really, properly respond to those viruses and correctly develop an immunity to them (in otherwords, it’s a waste of time and money to do it then).
Many people feel that there is evidence of another possible problem associated with modern vaccines. In the past, “live” vaccines were perishable and were kept cold or frozen to “preserve” them until used. Modern vaccines, however, have various preservatives added to them to prolong their shelf-life so that they can be stored at room temperature practically indefinitely (again, that makes things more convenient for the doctors and drug companies). However, there is much current debate/controversy over whether the preservative thimerosal, used especially in the “MMR” (measles, mumps, and rubella) vaccine, is a factor in autism. The feds, of course, deny any link between the two, but other people feel that there’s some pretty strong evidence linking them. NON-THIMEROSAL VACCINES ARE AVAILABLE. Many pediatricians’ offices routinely stock the standard, thimerosal-containing versions, but if parents are insistent and persistent, the doctor’s office can obtain the non-thimerosal versions. If they refuse and that’s something that’s important to you, then it’s time to go find a different doctor. On the other hand, I have heard from some students that their pediatricians will only use the non-thimerosal versions.


Background Information

Links to Related Information on Our Web Server

The following Web pages contain information related to immunity and the immune system, as well as bacterial and viral diseases.

Bio Lecture Immune System
Information on the various defense mechanisms our bodies use to fight foreign invaders
Bio Lecture Viruses
General information on viruses, plus a discussion of common, pathogenic viruses
Bio Lecture Bacteria
General information on bacteria
Bio Lecture Bacterial Diseases
Information on a variety of bacterial disease organisms

Your Assignment
Research a Disease or Disorder

There will be only one, combined assignment for this week’s topics (skeletal, immune, and excretory systems). Thus even though this will appear on each of those three pages to remind you, you only need to do it once. Pick a disease or disorder that affects humans, and do library and/or Web research to find out more about that disease (see below). Suggestion: get in touch with your classmates via e-mail (addresses available from the Check Grades (and Class E-Mail List) Web page) to find out what each other are doing so everybody doesn't do the same thing. As a suggestion, it seems like AIDS is almost “overdone,” these days – it might be more interesting to pick something a bit more “unusual.” If you’re looking for ideas for “different” sorts of things, a few things that come to mind include Hansen’s disease, androgen insensitivity syndrome, scurvy, kuru, beriberi, hemophilia, malaria, sickle-cell anemia, syphilus, bubonic plague, mononucleosis, human papilloma virus, etc., etc. Malaria has recently become a “hot topic.” A couple of Web sites which may be of use include The Merck Manual Online and OMIM Home Page (OMIM deals specifically with genetic conditions). The grading criteria for this assignment are given below, and you should also refer to those as you work on the assignment. A total of 30 points is possible.

    For the disease or disorder you have chosen:
  1. As you research this condition, if you find any other good Web sites with general information, please record their URLs so we can share them with other students
  2. What causes that disease/disorder? Is it caused by a disease organism (virus? bacterium?) or is it genetic or accidental or . . . ?
  3. How/when was this disease/disorder “discovered” or categorized/described? By whom?
  4. What is the primary/main body system that it affects, and how does it affect that system – what “problems” does it cause?
  5. What other systems of the body are affected, and how? How does it all “fit together?” (For example, given what you’ve learned about diet/nutrition, how might having a broken bone affect the functioning of your immune system?)
  6. What are the signs and symptoms of that condition (Hint: do you know the “official” difference between “signs” and “symptoms”?)
  7. How is this condition diagnosed? Is it “obvious” or are any tests run to determine if someone has it (if so, what kind of tests)?
  8. How is this condition treated/managed? Does eating a good diet or some kind of special diet help? If a person is given drugs for this condition, can you find out anything about those drugs – are they addictive, are there any side-effects, are there any major drug interactions with other drugs the person may be taking? If surgery is involved, how complicated is the surgery and what is the “success rate” of that surgery?
  9. Is this something permanent that requires ongoing treatment, or is this something from which a person will recover? (For example, while a person usually recovers from mono or chicken pox or cold sores, all of these stay permanently in the person’s body.)
  10. Is there any interaction between this disease/disorder and any other conditions present in a person’s body? (For example, sickle-cell decreases susceptibility to malaria and hypertension increases chances of stroke.)
  11. Is it contagious? If so, how is it spread? How likely is it that a person could get this from someone else? Can it cross the placenta and affect an unborn baby? (For example, both rabies and German measles can do that.)
  12. We’re a bit ahead of ourselves here, because we haven’t discussed genetics, yet, but if it’s a genetic disorder, what is its “pattern of inheritance”? Find out if it’s a dominant or a recessive gene – what are the chances that a parent who carries that allele will pass it on to a child? Is it a “sex-linked” allele (is it on the X or Y chromosome), or is it “autosomal” (on the “regular” chromosomes)?
  13. Can any other species of organism besides humans get this? Can it be transferred back and forth between that species and humans?
  14. What is the incidence of this disease/disorder? How many/what percentage of the population have it? What are the chances that you or someone from your family could have/get this?
  15. Is it more prevalent among certain ethnic groups or populations of people or parts of the world, or is it equally present everywhere?
  16. Are people of all ages, both sexes affected or does it affect some more than others?
  17. What are some of the “urban legends,” misconceptions, “old wives’ tales,” and other false “information” about this condition, and what are the true facts in opposition to the false beliefs?
  18. Did this condition ever play an important role in human history? (For example, both hemophilia and bubonic plague have done so in very different ways.)
  19. At this point, if you are a registered student, you should submit your work.

Grading Criteria

1.   Cause of Disease/Disorder:
2 — The cause of the disease/disorder was thoroughly researched and accurately and clearly presented
1 — The cause of the disease/disorder was adequately researched and presented
0 — Information on the cause of the disease/disorder was sketchy and/or mostly incorrect
2 — Thorough discussion of pre-existing conditions that increase chances of getting or exacerbate the condition was also included
1 — At least some mention was made of pre-existing conditions that increase chances of getting or aggravate the condition
0 — Either no or incorrect information on effects of pre-existing conditions was included
2.   Discovery of Disease/Disorder:
2 — The history of the discovery/description of this condition was thoroughly researched and accurately and clearly presented
1 — The history of the discovery/description of this condition was adequately researched and presented
0 — Information on the discovery of this condition was sketchy and/or mostly incorrect
2 — This information was presented in a manner that was entertaining and fun to read
1 — This information was adequately presented
0 — Presentation of this information was monotonous and lacked interest
3.   Signs, Symptoms, etc.:
2 — The signs, symptoms, and effects on the body systems were thoroughly researched and accurately and clearly presented
1 — The signs, symptoms, and effects on the body systems were adequately researched and presented
0 — Information on the effects of this disease/disorder was sketchy and/or mostly incorrect
2 — The student clearly demonstrated that (s)he knows the difference between “signs” and “symptoms”
1 — The delineation between “signs” and “symptoms” was included and was at least partially correct
0 — “Signs” and “symptoms” were not delineated or were incorrectly distinguished from each other or most manifestations of the condition were assigned to the wrong category
4.   Diagnosis & Treatment:
2 — The diagnosis and treatment of this condition were thoroughly researched and accurately and clearly presented
1 — The diagnosis and treatment of this condition were adequately researched and presented
0 — Information on the diagnosis and treatment of this condition was sketchy and/or mostly incorrect
2 — Thorough discussion of role and usefulness of diet and/or “alternative” therapies was also included
1 — Effectiveness of diet and/or “alternative” therapies was at least mentioned and partially discussed
0 — No mention made of effects/influence of diet and/or “alternative” therapies
5.   Spread & Distribution:
2 — The prevalence, distribution, and means of acquisition were thoroughly researched and accurately and clearly presented
1 — The prevalence, distribution, and means of acquisition were adequately researched and presented
0 — Information on the prevalence, distribution, and means of acquisition was sketchy and/or mostly incorrect
2 — Discussion of likelihood of contracting and means of prevention was thoroughly presented
1 — Likelihood of getting and means of prevention were at least mentioned
0 — No mention made of how to keep from getting this disease/disorder or information presented was incorrect
6.   Misconceptions & Role in History:
2 — Information on misconceptions associated with this condition and its role in history was thoroughly researched and accurately and clearly presented
1 — Information on misconceptions associated with this condition and its role in history was adequately researched and presented
0 — Information on misconceptions and/or the role in history was sketchy and/or mostly incorrect
2 — This information was presented in a manner that was entertaining and fun to read
1 — This information was adequately presented
0 — Presentation of this information was monotonous and lacked interest
7.   Overall:
2 — The grammar, English usage, punctuation, and spelling were very good
1 — The grammar, etc. were OK
0 — The grammar, etc. were poor
2 — The student, obviously, went beyond the minimum requirements of the assignment
1 — The student adequately completed the assignment
0 — The student completed considerably less of the assignment than what was required
2 — It is evident that the student used much insight, thoughtfulness, and critical thinking when completing this assignment
1 — The student adequately thought about the assignment – there was, perhaps, a bit of “fuzzy thinking” in a couple places
0 — The assignment gives the appearance of being “slapped together” just to get it done, with little evidence of thoughtfulness
Total Possible:
30 — total points

Copyright © 2006 by J. Stein Carter. All rights reserved.
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