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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 ...


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 ...


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 ...


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


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 ...


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

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 ...


1

A quick answer for now (I'll add details as I find): The infection of B from A would be zoonosis. This transfer may not have followed a classical route of infection. For example the case of hantavirus pulmonary syndrome (HPS), the zoonosis occurs throuch the rodent (primary host) droppings. Other example is that of avian influenza- the zoonosis doesn't ...


1

Just wanted to add that this is a common problem with vaccines. ...consider an actual measles outbreak in Colorado in December 1994.5 Out of 625 children exposed to the disease, 17 got measles. Of those 609 who had previously been vaccinated, only 10 (or 1.6%) developed measles. Of the 16 children who were not immunized, 7 (or 44%) developed measles. ...


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

The Center for Disease Control is a great source for disease statistics. I didn't find a chart with common disease incidence on their website, but if you search for a specific disease you should be able to find the incidence. http://www.cdc.gov/nchs/


1

For myself, I've not been terribly impressed with the use of keyword searches and the like as methods of predicting influenza or other diseases. They are, when it comes down to it, somewhat glorified extensions of a syndromic surveillance system, just for "I feel sick" instead of "Honey, pop down to CVS and pick up some NyQuil?" It's also apt to get you ...


1

Leon Gordis' "Epidemiology" was my textbook in undergrad and it was quite easy to follow. It's a small textbook as well so you can read through in no time.



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