If influenza is in the top *ten* killers then what is the _#1_ killer? Which place is influenza in?

In the US, Influenza is #7 and #1 is cardiovascular disease.

What is *Epidemiology* ?

Epidemiology is the study (or the science of the study) of the patterns, causes, and effects of health and disease conditions in defined populations. It is the cornerstone of public health, and informs policy decisions and evidence-based practice by identifying risk factors for disease and targets for preventive healthcare. Epidemiologists help with study design, collection and statistical analysis of data, and interpretation and dissemination of results (including peer review and occasional systematic review). Epidemiology has helped develop methodology used in clinical research, public health studies and, to a lesser extent, basic research in the biological sciences.

What is a low-grade fever?

You already got a good answer, I would just add: Low grade fever is easily overlooked in some chronic influenza-like illnesses. The common explanation is that it's the body's reaction after an infection, but as I learn from skilled specialists it's a sign of an still active infection, often hard to detect by tests.

what is the maximum temperature our body can reach during a fever?

A fever cannot cause brain damage unless it reaches 107.6 degrees Farenheit (42 degrees Celsius) and stays there for an extended period of time. Since your brain has a built-in thermostat that does not allow your core temperature to rise above 106 degrees Farenheit (41.1 C) during an infectious process, it's virtually impossible to experience brain damage from a fever caused by a bacterial or viral infection. The majority of fevers don't reach 105 (40.5 C) degrees.

What are the complications of the influenza virus?

flu can cause more serious health problems or flu complications such as sinusitis (sinus infections), bronchitis, or even pneumonia.

When she mentioned the 1918-1919 influenza virus epidemic, was she talking about the Typhoid Epidemic with Typhoid Mary and all that?

"Typhoid Mary" (who has been blamed far more than she deserves) was in quarantine and exiled from 1907-1910 and then from 1915 to 1938, the year she died of complications from a previous stroke. So during the 1918-1919 period, Mary Mallon was not in a position to cause problems with typhoid fever. Her situation doesn't really have anything to do with flu. http://www.snopes.com/medical/disease/typhoidmary.asp http://www.pbs.org/wgbh/nova/body/typhoid-mary-villain-or-victim.html Flu and typhoid fever are different diseases and caused in completely different ways. Typhoid fever is caused by a bacterium with a huge name like this: Salmonella enterica ssp. enterica, serovar typhi, but let's just say Salmonella typhi, for short. :-) But, flu is caused by influenza viruses. Remember that viruses and bacteria are not the same. Bacteria can be killed by antibiotics, viruses can't. This is the reason you should NOT take antibiotics when you have a viral infection, such as the flu, because antibiotics cannot kill viruses. Here are some sites you can check out for some very interesting and specific details about these topics. http://www.onhealth.com/salmonella/article.htm http://www.cdc.gov/flu/about/viruses/

Main content

Course: Stanford School of Medicine > Unit 1

Lesson 2: Influenza

Flu Epidemiology

Google Classroom

The flu has been causing disease and death for a long time. Get a feel for exactly how many folks are affected each year by this disease. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video. Created by Stanford School of Medicine.

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2012396
Posted 11 years ago. Direct link to 2012396's post “If influenza is in the to...”
If influenza is in the top ten killers then what is the #1 killer?
Which place is influenza in?
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(11 votes)
Answer
- Kaelen Davis
  Posted 11 years ago. Direct link to Kaelen Davis's post “In the US, Influenza is #...”
  In the US, Influenza is #7 and #1 is cardiovascular disease.
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  (10 votes)
Enn
Posted 10 years ago. Direct link to Enn's post “What is *Epidemiology* ?”
What is Epidemiology ?
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(5 votes)
Answer
- katelynn hopple
  Posted 10 years ago. Direct link to katelynn hopple's post “Epidemiology is the study...”
  Epidemiology is the study (or the science of the study) of the patterns, causes, and effects of health and disease conditions in defined populations. It is the cornerstone of public health, and informs policy decisions and evidence-based practice by identifying risk factors for disease and targets for preventive healthcare. Epidemiologists help with study design, collection and statistical analysis of data, and interpretation and dissemination of results (including peer review and occasional systematic review). Epidemiology has helped develop methodology used in clinical research, public health studies and, to a lesser extent, basic research in the biological sciences.
  Comment on katelynn hopple's post “Epidemiology is the study...”
  (7 votes)
Max wang
Posted 10 years ago. Direct link to Max wang's post “what is the maximum tempe...”
what is the maximum temperature our body can reach during a fever?
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(3 votes)
Answer
- 00015651
  Posted 10 years ago. Direct link to 00015651's post “A fever cannot cause brai...”
  A fever cannot cause brain damage unless it reaches 107.6 degrees Farenheit (42 degrees Celsius) and stays there for an extended period of time. Since your brain has a built-in thermostat that does not allow your core temperature to rise above 106 degrees Farenheit (41.1 C) during an infectious process, it's virtually impossible to experience brain damage from a fever caused by a bacterial or viral infection. The majority of fevers don't reach 105 (40.5 C) degrees.
  Comment on 00015651's post “A fever cannot cause brai...”
  (8 votes)
Curiosity
Posted 11 years ago. Direct link to Curiosity's post “What is a low-grade fever...”
What is a low-grade fever?
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(4 votes)
Answer
- Tore Nicolai Fjelldal
  Posted 11 years ago. Direct link to Tore Nicolai Fjelldal's post “You already got a good an...”
  You already got a good answer, I would just add: Low grade fever is easily overlooked in some chronic influenza-like illnesses. The common explanation is that it's the body's reaction after an infection, but as I learn from skilled specialists it's a sign of an still active infection, often hard to detect by tests.
  Button navigates to signup page
  (2 votes)
dinominodino
Posted 10 years ago. Direct link to dinominodino's post “What are the complication...”
What are the complications of the influenza virus?
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(3 votes)
Answer
- katelynn hopple
  Posted 10 years ago. Direct link to katelynn hopple's post “flu can cause more seriou...”
  flu can cause more serious health problems or flu complications such as sinusitis (sinus infections), bronchitis, or even pneumonia.
  Button navigates to signup page
  (2 votes)
saskiabaylee
Posted 8 years ago. Direct link to saskiabaylee's post “does anyone know how i ca...”
does anyone know how i can cite this video?
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(1 vote)
Answer
L
Posted 10 years ago. Direct link to L's post “If you felt sick that soo...”
If you felt sick that soon--when you see your family after the flight--wouldn't the actual exposure in which you "caught the flu" have been at least a full day before? (Unless you were on a really long flight.) At
0:24
it sounds as if the speaker is saying that you start feeling symptoms a few hours after exposure to the flu virus. I do understand that noticing all of the sick people on the flight would be consistent with other, earlier exposures in your previous locations. Maybe the timeline is too simplified to give an accurate picture of the timing here?
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(1 vote)
Answer
- nohunt18
  Posted 8 years ago. Direct link to nohunt18's post “I believe the speaker tri...”
  I believe the speaker tried just to simplify the problem but may not have done the best job
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  (1 vote)
manahanrojaypuch
Posted 8 years ago. Direct link to manahanrojaypuch's post “People can catch flu but ...”
People can catch flu but touching you?
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(1 vote)
Answer
Kutili
Posted 10 years ago. Direct link to Kutili's post “How many of these 20-40 t...”
How many of these 20-40 thousand annual deaths from influenza occur in immunodeficient people?
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(1 vote)
Answer
- nohunt18
  Posted 8 years ago. Direct link to nohunt18's post “I would say between 10-15...”
  I would say between 10-15 thousand, but I may be wrong
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  (1 vote)
NotMyRealUsername
Posted 11 years ago. Direct link to NotMyRealUsername's post “When she mentioned the 19...”
When she mentioned the 1918-1919 influenza virus epidemic, was she talking about the Typhoid Epidemic with Typhoid Mary and all that?
Button navigates to signup pageButton navigates to signup page
(0 votes)
Answer
- L
  Posted 10 years ago. Direct link to L's post “"Typhoid Mary" (who has b...”
  "Typhoid Mary" (who has been blamed far more than she deserves) was in quarantine and exiled from 1907-1910 and then from 1915 to 1938, the year she died of complications from a previous stroke. So during the 1918-1919 period, Mary Mallon was not in a position to cause problems with typhoid fever. Her situation doesn't really have anything to do with flu.
  http://www.snopes.com/medical/disease/typhoidmary.asp
  http://www.pbs.org/wgbh/nova/body/typhoid-mary-villain-or-victim.html
  Flu and typhoid fever are different diseases and caused in completely different ways. Typhoid fever is caused by a bacterium with a huge name like this: Salmonella enterica ssp. enterica, serovar typhi, but let's just say Salmonella typhi, for short. :-) But, flu is caused by influenza viruses.
  Remember that viruses and bacteria are not the same. Bacteria can be killed by antibiotics, viruses can't. This is the reason you should NOT take antibiotics when you have a viral infection, such as the flu, because antibiotics cannot kill viruses. Here are some sites you can check out for some very interesting and specific details about these topics.
  http://www.onhealth.com/salmonella/article.htm
  http://www.cdc.gov/flu/about/viruses/
  Button navigates to signup page
  (2 votes)

Video transcript

Let's imagine that this is you, and you are headed home for the holidays. So you board a plane, and you notice while you're on this plane that the people around you are pretty sick. The guy next to you looks like he has a fever. Maybe the flight attendant is coughing. So you head on home. And although you're excited to see everybody in your family, you are feeling completely run down. And so you decide to head to bed, and hopefully you'll feel better tomorrow. Unfortunately, you don't feel better the next day. You have a very high fever. You don't even have the strength to get out of bed for a few days. And when you finally start to feel better, you notice that you're not the only person in your house who's sick. Your dad is sick. Your mom is sick as well, maybe some of your siblings. You call your best friend. They are sick, and their entire family is sick. Maybe you talk to a neighbor and someone on your street, you learn, has died from this illness. And news reports say that this is not unique to your town, but it's happening all over the state and all over the country. Now, this is a really scary situation. But unfortunately, it's not one that is out of the realm of possibility. In 1918 and 1919, this was a particularly bad influenza season. In fact, it was so bad that it led to approximately 50 to 100 million deaths worldwide. And this is a pretty famous picture from that era of a makeshift hospital. There were so many sick people during this flu season that hospitals couldn't provide enough beds and resources for the patients who needed it. Even during a so-called regular flu season, every year the influenza virus causes a lot of damage. Flu is a top 10 killer in the United States, and it leads to approximately 200,000 hospitalizations every year due to complications of the influenza virus. In addition to the 200,000 hospitalizations that we have every year in this country, approximately 20,000 to 40,000 people die every single year, 20,000 to 40,000 deaths on an annual basis. So you can see that influenza is not something to be taken lightly, but can lead to very serious consequences. But luckily, there is something that can be done. In fact, there's something that you can do about this. As someone who's learning this training, you're learning how to vaccinate people in your community. The modern influenza vaccine is approximately 70% effective in preventing influenza infection, and so this is a great way to help prevent illness and death.