Case Fatality Rates and Modern Medicine's Role in Reducing them

I have read a few places recently where people have pointed out that medicine is ineffective, doesn't work, there's no point in using it, etc.Well, you'd have to be pretty ignorant to believe that, but it made me wonder just how our infections might be if we didn't receive the treatments we have available today. I figured a good indication of that would be to compare the case fatality rates of untreated diseases to those that were treated. If a treatment significantly reduces the CFR, it's obviously doing its job. This doesn't even take into account the less-severe symptoms that are usually experienced when treated, but that's a lot more subjective and harder to judge with numbers. I wasn't able to find a comprehensive list of what I was looking for so I have decided to compose a list of different diseases including their case fatality rates when left untreated as well as the CFR when they are treated. Below I have highlighted a few things, and at the bottom is the table of multiple diseases and their CFRs. I plan on adding more and updating this over time.

Ebola
The Ebola virus is weird because we still don't even know where it come from. We are sure of a few things, though. It's found in Africa and it's almost certainly a zoonosis, meaning it comes from an animal. The case fatality rates among incidence of the ebola virus averages about 68%, though it varies from 30-90% depending on the outbreak. Most current treatment is just supportive, though there has been research on a treatment (in rhesus monkeys) which reduced the CFR to 33%. The strain used in the research previously had a CFR of almost 100%.

Bubonic Plague
Yersinia pestis is the culprit here, and when treated, only causes death in 1-15% of infected individuals. When left untreated, it's associated with a 40-60% fatality rate. With modern medicine and sanitary habits, this organism doesn't really cause many problems. This is the same organism that is thought to have wiped out 1/3 of Europe's population in the 14th century!

Smallpox
The Smallpox virus was declared officially eradicated in 1979. Now, only a select few places are holding onto the virus (one being the CDC), and they are under secure protection to prevent bio-terrorist events. When smallpox was prevalent, a CFR of about 30% was observed. This varied, however, with some strains being almost a guaranteed death. Even people who are vaccinated can be susceptible to the disease they've been immunized against, and this was no different for smallpox. However, those who are vaccinated typically experience milder symptoms, as is supported by the lower, 3% CFR of people who contracted the virus that had been previously immunized against it.

                                        An average case of smallpox. Glad this isn't still around!

HIV/AIDS
It is true that an infection of HIV doesn't directly kill you. This in no way means that it's not deadly, though. HIV infects and destroys your CD4+ Helper T Cells to a point that it renders your immune system useless. Once a person's CD4+ count drops to a certain point (<400/uL), they are diagnosed with AIDS. Without a properly functioning immune system, a person is susceptible to being severely infected by pathogens that normal people live with each and every day without any problems, such as Pneumocystis jiroveci and Candida albicans. Treatment is continuing to improve, fortunately. Twenty years ago, only 20% of people diagnosed with the condition could expect to live for 5 years. Now, that number is over 80%.

Cancer
Cancer is a debilitating condition caused by the uncontrolled growth of abnormal cells. When it goes untreated, it will almost always eventually result in death because it impairs the normal function of the body. Early detection of cancer is the best thing you can do to stop it. Cancer becomes more deadly the longer you leave it uncontrolled, and by the time it metastasizes it will be deadly more often than not, even when given the best treatments. Many years ago, being diagnosed with cancer was basically a death sentence. With today's treatments, many people will survive the illness without a problem, especially when caught early. There is so much promising research being done that I believe will essentially make cancer a non-issue in the future. Because of the relative difficulty of finding cases that went untreated combined with the fact it is almost always deadly when not treated, I didn't fill in the CFR (untreated) section for cancers.

Note: Though case fatality rate and mortality rate aren't technically the same, you will often see them used synonymously. Case fatality rate refers to how likely an infection will result in death. For example, 100 people are diagnosed with AIDS, and 50 die, giving a CFR of 50%. Mortality rate is the measurement of deaths in a population. For example, AIDS kills 2.7 out of every 100,000 people.

Disease	CFR (untreated)	CFR (treated/vaccinated)
Acute Lymphoblastic Leukemia	---	15%*
Acute Myelocytic Leukemia	---	30-40%*
Bone Cancer	---	30%*
Breast Cancer	---	16%*
Bubonic Plague	40-60%	1-15%
Chronic Myelocytic Leukemia	---	20-40%*
Colorectal Cancer	---	41%*
Diphtheria	5-20%	0%
Ebola	68%	---
HIV/AIDS	80-90% (5 yrs)	15% (5 yrs)
Leishmaniasis	10%	0%
Liver Cancer	---	72%*
Malaria (P. falciparum)	20-25%	<1%
Measles	15-25%	0-1%
Melanoma	---	21%**
Pertussis	3.7%	0-1%
Prostate Cancer	---	1%*, 2%**
Rabies	~100%	~0%
Smallpox	30%	3% (vaccine)
Syphilis	25%	0%
Testicular Cancer	---	1-4%*
Tetanus	58%	0-10%
Trypanosomiasis	80%	6%
Tuberculosis (active)	>50%	<18%

Note: Cancer numbers are fatality rates, not survival rates
*Cancer CFRs based on a 5 year survival rate among early stages (through stage 2)
**Cancer CFRs based on a 10 year survival rate among early stages (through stage 2)

References

http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA430462
http://www.cancer.org/
http://emedicine.medscape.com/article/829233-overview#a0199
http://www.cdc.gov/vaccines/pubs/pinkbook/downloads/meas.pdf
http://www.ncbi.nlm.nih.gov/pubmed/9557424
http://www.mass.gov/eohhs/docs/dph/aids/2006-profiles/dying-aids.pdf
http://ci.vbi.vt.edu/pathinfo/pathogens/falciparum.html

My First Blog

I don't plan on posting that much (then again I don't really know how much is considered often since this is my first blogging experience), but I figured this would be a nice place to gather my thoughts, ideas and research. It won't be too boring (or so Kaitlin assured me), so feel free to read!