Infectious Diseases First Reader

           There are so many things to consider when one mentions the word disease. As noted from the readings, the concept is dense; there are a variety of mechanisms, hypotheses, causations, types, and transmission methods. Because I do want to become a physician in the future, I am studying a lot of disease mechanisms and triggers in my biology courses. I feel like the material is highly relevant to me in understanding the basic science behind diseases.

            The chapters in Medical Anthropology overlapped with a lot of the information I had previously been exposed to, such as the immune system and antibody/antigen recognition, viral infections, and modes of pathogenic transmission. It even reinforced a lot of my research I was doing for my 20% project on allergies. Though I am specifically analyzing food allergies, the idea is essentially the same. A food allergy is nothing more than an inflammatory response triggered by your immune system when it comes across a foreign antigen. Those allergic to specific foods cannot properly recognize the antigens found in that food.

            What I found interesting were the proposed hypotheses for rates of allergy and asthma. To me, it seems as if the Hygiene Hypothesis would be more relevant to the spread of diseases rather than the spread of allergies. Hygiene typically involves the killing of bacteria and microbes instead of masking of antigens, so it was surprising to me that the Hygiene Hypothesis has become prominent. On the same page as hygiene, I do believe that the increased need for cleanliness in developed countries has contributed to infections. Similar to antibiotic resistance, the continuous repression of less harmful forms of illness and pathogens can lead to growth in rates. However, how should this be combated? It’s unrealistic to expect patients and physicians not to take immediate action in the face of “danger”. Instead of limiting people’s resources, I believe focusing on new research and treatment methods is moving in the right direction.

Researcher Viruses in Contaminated Water

I did  not see Group 4 for this week - not sure if I need to post a blog.

So I decided to play it safe and did some research on viruses in contaminated water. A good example of parasites in contaminated water is in the Sub-Saharan in Africa and South Asia. In these developing countries there are people living in extreme poverty. In addition, these individuals do not have access to safe water, clean sanitation, nor instructions for good hygiene. Large areas in Asia have no access to sanitary disposal of human waste. Therefore, failure to dispose of waste properly can contaminate water and food sources leading to an increase in the transmission of pathogens orally. Consequently, this has lead to the spread of waterborne parasites that infect and kill 8.8 million children a year. These parasites are ingested orally, enters into the  intestines, and effect the liver and brain. As a result, many are ill, their growth are stunted, whether or not children enroll in school, and it impairs proper mental and physical development.

There are numerous parasites and pathogens that contaminate children as they are bathing or playing in the water. Unfortunately, it is the same body of water that is used for defecating, or cleaning fecal matter from the body or soiled clothes. Other parasites and pathogens include waterborne parasites; Entamoeba histolytica, Giardia Intestinalis, Cryptosporidium Parvum.
In addition, there are bacterial enteropathogens; salmonella (found in chicken, ground beef, and turtles), Shigella (can be found in men who have sex with men), Escherichia Coli, Vibrio Cholerae.

I found this information in my Global Health textbook by Richard Skolnik (2012), chapter 8, and
The Center for Disease and Prevention (2010). www.cdc.gov.

First Reader: How to heal

My sister-in-law was ill with the flu a few weeks ago and needed to get back on her feet quickly to go back to work. My immediate response was to encourage her to ask her doctor for Tamiflu which is a drug that works to treat the inconvenient symptoms of the flu virus. But does the convenience of symptom solving drugs create a future of inconveniences? According to chapters eight through ten the answer is probably.

Being a History major, I like to apply everything we learn in class to where it might fit most appropriately on a historical timeline. As nerdy as this may make me the biggest event I could associate with these readings was the Black Death. A disease spread through massive population shifts to urban environments and through the transmission of rats the plague was one of the most deadly events in human history. Of course, people of that time believe that the plague was a punishment bestowed by God. Now we are able to determine the spread of disease that facilitate events like these. This also holds true for the increase in disease as a result of the industrial revolution that the chapters mention. Closer contact with animals and people, the settling of towns, and changes in diets are all factors that increase the spread of disease.

These events bring us to today. We still have epidemics like the most recent flu which claimed multiple lives this year. It makes me wonder that if epidemics of the past claimed nearly a third of the population (black death) is it better to treat just the symptoms so that we can quickly return to our day to day activities or should we let our bodies natural response take over. Personally, I think drugs like Tamiflu and Dayquil should be used in moderation although I am certainly guilty of overusing them in an attempt to go to work or school sooner. Maybe I should take a dose of my own “natural” medicine instead.

Viruses and Us-First Reader

I found this week’s reading to be interesting and applicable to my major. As an MCB major, I have studied the effects of bacteria and viruses in living organisms.  The most interesting piece of information that I learned in my classes is the way of which viruses propagate duplication within a bacteriaphage (infected bacteria cell). Once the bacteria cell is infected, the virus must decide to go into a lytic or lysogenic phase.  

Lytic phase occurs when the host cell is deemed healthy by the virus and can duplicate the virus and eventually be lysed (killed) to spread the newly formed viruses.  The lysogenic phase occurs when the host cell is not very healthy.  What occurs under these conditions is the integration of the virus’ genetic information into the host cells genome.  Once the host cell is healthy enough then the cell will go into the lytic phase. 

This was an explanation of the reading in chapter 8 where it stated:

“One other option for the virus is to simply remain in the cell without causing any damage and without spreading, such that the host becomes a carrier of the virus.  The virus can remain latent and noninfectious until the immune function is suppressed and then symptoms of infection may emerge. (Ch. 8 pg 220)”

Another topic that one of my classes studied was the utilization of vitamin K produced by intestinal host bacteria.  The human body cannot synthesize vitamin K so that is why we have created a symbiotic relationship with this form of bacteria.  Vitamin K is used to strengthen our immune system helping in coagulation and absorption of other biological nutrients.

First Reader - Disease and the Agricultural Revolution

I found very interesting in the text, the discussion about the impact of the agricultural revolution and its effects on infectious disease. While, I feel that in the West the agricultural revolution is still largely hailed as a step towards civilization, it was as well a step towards the epidemic diseases we still live with. Early humans were not sedentary, following practices of hunting and gathering, they moved around following food and did not establish large urban areas. The authors of the text note that the pathogens that effected early humans were ectoparasites, protozoa, fungi, bacteria, and zoonotes (diseases that transfer between species, ex. Tuberculosis from cattle to humans (p. 257)). These pathogens usually do not lead to epidemics and spread slowly through populations (p. 255). With the advent of agriculture as well came sedentary populations that begin to live in much large population densities than are seen among hunter-gatherer groups. As well, dealing with human waste, which was not an issue for mobile hunter-gatherer groups, becomes a major potential health risk for urbanized populations. With the rise of more domestication of animals came more zoonotes. Diets became less balanced, and malnutrition became more widespread. The rise of trade helped to spread diseases through in between distant populations. These conditions are conducive to the rise of things like plague or smallpox that have the potential to erupt into major epidemics with the potential to kill mass amounts of people (p. 256-59). While we have been able to control many deadly epidemic disease such as smallpox for some years, the threat of resistant strains may result in massive epidemics in the future.

First Reader - Treating adaptive responses to infectious disease

Our bodies handle infectious diseases in a couple different ways; there are adaptive responses, such as coughing, sneezing, vomiting, and diarrhea, and immune responses. Whether it is because adaptive responses are associated with sickness or because they are just really unpleasant, there seems to be a negative perception of them.

It isn’t really uncommon then to want to treat the uncomfortable symptoms that accompany infectious disease. But in fact, suppressing the adaptive responses your body has can have harmful repercussions as far as overcoming the infection goes. Our bodies have adapted these reactions to rid itself of the pathogens. Responses like vomiting or coughing are the body’s means of physically flushing or expelling as much of the pathogen as possible.

So why do we generally act to treat these symptoms through suppression if this causes the body to house more of the pathogen and work harder to destroy it?

In many cases, these symptoms are thought of as part of the pathogen and not the body’s protective response to it. Pharmaceutical companies that fund the clinical treatment of these adaptive responses are unlikely to support the idea that simply resting and recuperating may be best to allow the body to fight the sickness.

Why should we have to suffer pain if we have the option not to? Chapter 8 of Medical Anthropology introduces the concept of a high ‘pain intolerance’ in the U.S. because of the option to treat adaptive responses. Along with this idea, if patients seek medical advice and what they get is recommendation to do nothing but take it easy, rest and recuperate, they may see that their money was poorly spent at the doctor’s office. Perhaps this could be remedied by the same advice with suggestions to take needed supplements afterwards to fortify bodily systems that were drained from the sickness?

People are expected to continue on with life even in the face of sickness. Our busy schedules don’t allow extraneous time to be sick, so naturally quick fixes of the symptoms of pathogens are widely sought after. But is this best for our health? And wouldn’t the medical community, entrusted with the responsibility to endorse health, have an obligation to direct us in the healthiest option, not just give us a drug to mask the symptoms?

At the same time, it may be a public health concern to not treat the symptoms if individuals are still going to participate in their social obligations. Coughing, sneezing, diahhrea are all the body’s way to expelling infection, therefore increasing its presence to the rest of a population and increasing other people’s susceptibility to it. 

Reader

After reading the article about aging I had many ideas come to mind. The one that struck me most is the fact that women go through menopause reason being natural selection. It was surprising to know that humans are born so early that they have to be dependent on their parents for a long time.  Therefore since menopause is onset around a certain age group it increases the survival of the mother and grandmother so that they can care for their offspring. I feel that menopause is displaced in our modern environment since child mortality varies on the place the fetus is born.  Though there s a higher chance for a child to survive if their mother dies giving birth now because there are relatives and if not others to care for the child. I also found it interesting that size and life span were correlated.  Since smaller animals like insects don’t live long due to extrinsic mortality and other reasons. I feel as if it isn’t that accurate because there are some beetles that live up to 40years, so I feel that it all depends on the environment the species live in. Therefore, they life expectancy depends on the species and environment as well as the parenting .

(Searcher) Platelets and Heart disease

Throughout this weeks reading we have journeyed into a world of evolutionary health issue such as chronic diseases. The most popular health narratives have been in the form of discussing chronic heart diseases. Origins of chronic diseases are imbricated due to a host of factors (as discussed in this weeks readings) like genetics, improper nutritional intake, sedentary life styles that has been embodied by Western society.

In the Article that I researched via Science News, “Heart Disease Linked to Evolutionary Changes That May Have Protected Early Mammals from Trauma” Perelman School of Medicine at the University of Pennsylvania explores rationales for the evolution of heart diseases in mammals. In this article there is a belief that, “The same features of blood platelets that may have provided an evolutionary advantage to early mammals now predispose humans to cardiovascular disease” But can we really blame natural selection for chronic diseases?

Thus, there is a belief that via an evolutionary lens that platelets are uses as clotting factors in case of injury and or trauma (Platelet- A small colorless disk-shaped cell fragment without a nucleus, found in large numbers in blood and involved in clotting) which the research believe is why individuals have heart disease. In this article it is said that, “Platelets are required to prevent excessive bleeding following traumatic injury, but they also form clots at sites of atherosclerotic plaques in the blood vessels that lead to stroke and heart attack”. This is interesting because we do use blood thinners such as Coumadin, Aspirin, heparin, and other blood thinners to prevent heart attacks and stroke, but are platelets really the source of heart disease? And what will happen to mammals if we lacked platelets? Dr. Khan do believe that platlets give humans an advantage

It was interesting to learn in this article that mammals have platelets but no other mammal do. And maybe we truly can blame evolution for chronic heart diseases, but also take ownership of other factors that cause hear disease as well. 

Source:http://www.sciencedaily.com/releases/2011/10/111018211341.htm

Searcher: Is Aging a Disease?

The article I found asks an interesting question: is aging a disease? The author, Kate Kelland, explains that although simply growing older (that is, having more birthdays and a growing chronological age) is normal, perhaps diseases of the elderly are not normal and that we should be able to treat them. Some scientists are saying that if we view aging itself as a disease, we will respond more to it by trying to come up with a "cure." Kelland notes that drug companies will not license medicines for something general such as aging. Kelland says that life expectancy is increasing and says that this must mean people are living longer. She also claims that with greater age comes greater instance of age-related diseases such as Alzheimer's. Once scientist says that we are approaching these diseases the wrong way--instead of looking at the individual diseases, we should be looking at aging and searching for a common mechanism for all age-related diseases. Kelland concludes the article by clarifying that this search to "cure" aging is not really an attempt to increase life-span, but an attempt to increase health-span and simply help people stay healthier in their old age.

I did notice that she made the claim that people are living longer--however, she used life expectancy to support this rather than life span. We discussed in class that people are not, in fact, living much longer; there are simply less people dying very young, but once people make it past childhood, the life span of humans has not really changed.

I was also skeptical at first of the attempt to find a "cure" for aging. It doesn't make sense to me to create more drugs to "solve" a problem that isn't really a problem. However, the clarification at the end of the article about the goal being to reduce age-related illnesses makes sense. Kelland mentions that researchers are also looking at preventative ways to reduce these illnesses, which I think makes perfect sense. However, the idea of redefining aging as an illness simply so that pharmaceutical companies can create more drugs to "fix" this problem is weird to me. Since humans' life span has not really changed, but age-related illnesses have, there is probably something we are doing, some lifestyle factor, that is causing such an increase of age-related illnesses. If we can fix that problem, we can easily improve "health-span."

(Searcher) Genes and Diseases

   Searcher:

    Today, we see scientists trying to better understand how geographic ancestry, families defined by their ancestors, and how individuals are defined by their own specific genetic can inform clinicians of possible variations in disease risks. In addition, the human genome project which aided the search for DNA variations in individuals and the continent of their ancestral origin, has provided new ways to look at genes and health. For example, African descended individuals are more likely to carry alleles promoting sickle cell anemia, and European descended populations are predisposed to cystic fibrosis.

   Based on known genes and shared ancestry, researchers are able to determine group related and individual genetic risks for chronic degenerative conditions. There are new clinical methods for genetic profiling; screening, counseling, and the development of pharmaceutical formulas for treatments of specific genes that cause diseases in individuals.

    I feel that race, genes, and your ancestral origin is not important in researching for new drugs and treatments of diseases. In sum, the primary focus in disease risks should aid primarily in finding cures for diseases regardless of your race, ethnicity, or origin. Let's stop fooling around and wasting idol time with frivolous things, and staying focused on saving lives.

(Searcher) Ancestral Heart Disease

Just a few weeks ago, Eryn Brown of the Los Angeles Times reported in this article that researchers conducted CT scans of mummies which ended up showing them predisposed to cardiovascular problems. This article somewhat challenges the week’s readings, particularly the causes of heart disease and the general presence of heart disease in our ancestors. In Chapter 21, Weil claims that atherosclerosis and congestive heart failure are primarily a result of agriculture and industry, our letting go of “ancestral lifestyles”, and our unhealthy modern environments. She states, “Epidemic heart disease was certainly not commonplace in…our past as a species. The reason our ancestors did not develop CHF is that the modern risk factors for heart diseases were all but absent in our ancestral environment.”

While it is true that our modern lifestyles have not exactly taken a turn for the healthier, researcher Caleb Finch notes, “There may be no environment or lifestyle which could eliminate atherosclerosis.” The mummies studied were “Egyptians who lived between 3100 BC and AD 364; pueblo dwellers who lived in what is now Utah between 1500 BC and AD 1500; Peruvians who lived between 900 BC and AD 1500 before Europeans arrived in South America; and Aleutian hunter-gatherers who were alive in the pre-industrial period around AD 1900” – non-Western inhabitants who were unlikely to have high-fat diets. Due to the findings of “calcium deposits of atherosclerosis in mummies from all four cultures” in the same places of the body, the researchers claim that age is the main factor that increases cardiovascular disease in both our ancestors and our modern selves. However, this study did not discover anything about the ultimate CHF in our ancestors (consistent with the reading), nor did it claim that heart disease was as much of an epidemic as it is today.