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17

There’s an XKCD comic which explains the problem. Unfortunately, that comic is too big to post here. Briefly, a p-value of 0.1 says (roughly) that there’s a 10% chance (0.1) of the observed result being as extreme1 as it is simply due to chance (sampling variation from a population), assuming the null hypothesis is true. Often, 5% is more or less ...


15

Interesting question and hard to answer definitively. First of all: It seems still pretty clear that the major (and by far most important) infection route comes from direct contact with infected people or their body fluids and that aerosol transmission is of far less significance. Ebola is infecting cells of the immune system (mostly macrophages and ...


14

Vaccines work by introducing an attenuated strain of the pathogen (or alternatively the antigens that are normally present on the pathogens surface) into the body, whereupon the body mounts an immune response. As this will (hopefully) be the first time that the body has encountered the antigens on the pseudo-pathogen's surface, the response is called the ...


12

MBQ and Rory M have already given decent answers on the "hows" of how the vaccine memory is formed. Now, for some twists: There are three (general) types of vaccine, all of which are meant to make your body "think" its being infected and provoke an immune response, while at the same time not causing active infection. They are: Live attenuated. These ...


12

This really depends on the environment, one study (listed below as reference 1) found that the Ebola virus can survive under ideal conditions on flat surfaces in the dark for up to six days - see the figure from the same publication. However, the virus is quite sensitive to UV radiation (see reference 2 for all the details) and most viral particles are ...


11

Duration of efficacy is typically determined by tracking the antibody titers of a cohort of subjects who have gotten the vaccine, and estimating based on the trajectory of those titers where they will eventually cross the threshold to the point where the vaccine no longer confers immune resistance. These estimates do get revised and estimated as time goes ...


11

It's mainly caused by swelling of large veins and by an increase in vascular permeability that leads to an accumulation of fluids in the nasal mucosa. These effects are mediated, at least in part, by bradykinin and histamine, and can be counteracted by epinephrine. These mediators are part of the immune response to the viral particles. You can read more ...


11

This is too long for a comment, so I put this in here: The main reasons are sociological. From the data I have read so far, this outbreak (actually these are two independent outbreaks, one in West-Africa and another one -not connected- in the Democratic Republic of Congo) is not exceptionally deadly in terms of Ebola. The death rate is about 60% which is ...


9

For some background, it is essential to know that Ebola is actually a group (genus) of ebolaviruses, each with different fatality rates. There are five known species of Ebola, and four are known to cause disease humans (WHO: Ebola virus disease; wikipedia). The known species of Ebola includes: Zaire ebolavirus (or just ebolavirus) Sudan ebolavirus ...


7

Disclaimer: I'm an infectious disease modeler, and generally pretty skeptical of "We modeled X like an outbreak!" claims, because many are just an exercise in curve fitting. Given that, the answer is both "Yes" and "No". "No": Murder as an act really isn't transmissible, and if its not transmissible, it can't be modeled as an infectious disease. "Yes": It ...


7

There have been some studies regarding the use of intensive UV light installations in surgical wards or other settings as a anti-microbial tool. Generally speaking, these are part of a general interest in non-cleaning based anti-microbials in hospitals, such as UV light, O3-based machines, and copper/silver coated surfaces. The answer to your question will ...


6

There are two books I'd highly recommend for someone starting to dabble in Epidemiology. The first is Kenneth Rothman's Epidemiology: An Introduction, which I'm affectionately going to refer to as "Baby Rothman" from hereon out for reasons that will become obvious. Baby Rothman is an excellent "getting your feet wet" book. It's simplistic, and clearly ...


6

In short, some of the B-cells (antibody producing lymphocytes) specified to deal with this agent go dormant after the vaccine stimulation -- when the real danger comes, they can proliferate quickly and flood it with new antibodies, also alerting the rest of the immune system.


5

Here is an online book of epidemiology for the uninitiated. I used it to get a basic understanding of epidemiology. http://www.bmj.com/about-bmj/resources-readers/publications/epidemiology-uninitiated


5

This is too long for a comment, so my thoughts about this here. The CDC Director said a few days ago after a visit in Africa "The window of opportunity is closing". This can happen. However, you are not getting contagious unless you show symptoms. This is different in other diseases like chicken pox or measles where you spread the virus before showing ...


4

I took a quick peek and HealthMap and their JavaScripts are publicly viewable. As such, I believe cross site scripting would be quite feasible. In other words, call their JavaScripts from a page you develop on your server to create a feed of the data you want. In this way, minimal effort on your part could leverage their data scraping efforts. If ...


4

MC4R, TMEM18, GNPDA2, KCTD15, NEGR1, BDNF, ETV5, MTCH2, and SH2B1 have also been identified as being associated with adult onset obesity risk, however FTO currently appears to be the one with the strongest evidence. For example see Thorleifsson et al. (2009), Elks et al. (2010) and Willer (2009)


4

Hamsters are considered the best animal model, most studied. C. difficile has been found in calves, ostriches, chickens, elephants, dogs, horses, and pigs, but its role in infection and its pathogenesis in animals are largely poorly understood and possibly underestimated


4

The difference in life expectancy between smokers and non-smokers appears to be at least 10 years on average, in a survey of American adults between 1997 and 2004. The same paper lists causes of death (higher among smokers than non-smokers, as measured by hazard ratio), although this is not exhaustive: lung cancer, other cancers, ischemic heart disease, ...


3

About diseases in general, that would concern the health dept. of the respective country government, and the govt. is the most probable source for such numbers. However, orpha.net has two reports with numbers concerning hereditary diseases, have a look at http://www.orpha.net/consor/cgi-bin/Education_Home.php?lng=EN#REPORT_RARE_DISEASES


3

There are different causes and mechanisms behind runny and stuffy nose. I cover them separately below. Runny nose My professor of pathoanatomy and pathophysiology says that the correct answer here is serous inflammation to the runny nose. Serous inflammation Marked exudation by relatively thin fluid Cold is caused by Acute respiratory viral infections ...


3

The stuffiness is due to edema or swelling of the mucous membrane covering the nasal cavity. The swelling is caused by vasodialatation or dialatation of the capillaries and leaky vessels which accumulate fluid within the mucous membrane. The runny nose is mainly due to hyperactivity of the mucous cells of the lining which causes vastly more secretion than ...


3

There are a number of reasons, generally, why a screening test may fail to decrease cancer mortality rates: The screening test may not be very good. I know this seems like an obvious one, but its something of a problem - a screening test will only reduce mortality if it catches cases that are both treatable and wouldn't be detected in time to treat using ...


3

The phenomenon Synesthesia is a neurological phenomenon in which a stimulus in one sensory or cognitive pathway triggers an experience in another. Some hallmarks:1 It tends to be developmental, arising early in childhood. It is involuntary. It is stable over time (i.e. the same stimulus leads to the same sensory experience). Epidemiology The best ...


2

I found Clinical Epidemiology by Robert and Suzanne Fletcher extremely useful to gain some quick insight in to the broad area of epidemiology during my first year of post-doc. It covers a wide-range of topic in clinical research and epidemiology in an accessible format with several examples and extensive illustrations.


2

You can use official sources such as hospital admissions, prescriptions for drugs fighting the disease you are tracking, sales of over-the-counter medicines. CDC (cdc.gov/flu/weekly/, cdc.gov/outbreaknet/outbreaks.html, etc), WHO, EuroFlu Weekly Electronic Bulletin map official clinical data, Aurametrix uses these sources. Several scientific studies have ...


2

I'd argue this actually belongs on CrossValidated. Essentially, the problem is one of how a GWAS study is conducted. By looking over an entire genome for associations, you're actually conducting thousands or millions of experiments, not the single experiment most statistics were designed to handle. As such, you're going to find many results that meet the ...


2

There are two other, but rather exotic possibilites which explain why people do not develop immunity after an diphtheria infection. These are unlikely to get to 6-8% of the cases which @Masi writes, but I am missing the reference here. The first possibility are people with chronic renal failure. They have problems with their immune responses since their ...


1

In this article they look at the development of natural immunity to diptheria in those who were vaccinated. I could not find any studies on people who had acquired it naturally. http://www.sciencedirect.com/science/article/pii/S0264410X97001485 They found that the development of immunity to diptheria vaccine depended on several factors: Time lapsed since ...


1

A friend told me, during a 3 minute discussion, that viruses that are endemic in host A and make repeated jumps to host B but can't be transmitted between individuals of species B, may slowly adapt (through these repeated jumps) to be able to be transmitted between individuals of host B and become epidemic. This is...mostly true. A good example ...



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