47 votes
Accepted

Does COVID-19 have a case fatality rate of 41%? Is this formula correct?

The definition of mortality rate that you've given does not match any practical definition I'm familiar with.* When people talk about the mortality rate of a disease, what they usually mean is the ...
Ilmari Karonen's user avatar
33 votes

Father gets chickenpox, but doesn't infect his two children. How is this possible?

If there was close contact, if the 90% rate is accurate, and if occurrence is independent in related individuals, then you would expect 0.10 * 0.10 = 1% of contacts with 2 potentially vulnerable ...
Bryan Krause's user avatar
  • 14.1k
20 votes

Does COVID-19 have a case fatality rate of 41%? Is this formula correct?

The equation you use for mortality is only really useful in the very long term for a known disease, when most cases have resolved. It's not very informative in the short-term, when the vast majority ...
Bryan Krause's user avatar
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20 votes
Accepted

Why do corticosteroids harm COVID-19 patients?

One of the primary purposes of corticosteroids is to suppress immune activity and inflammation: that's exactly why they are used in asthma. Of course the immune system has an actual job besides ...
Bryan Krause's user avatar
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19 votes
Accepted

A cheap and easy inactivated vaccine for COVID-19

The only approved inhaled vaccine is the flu vaccine delivered intra-nasally. It uses a live attenuated virus. There are a whole list of people who should not receive it because it's a live virus, ...
Graham Chiu's user avatar
  • 13.3k
14 votes

Does COVID-19 have a case fatality rate of 41%? Is this formula correct?

I'd like to chime in with an explanation of what exactly is wrong with the calculation offered in the question, rather than just saying "it's a wrong formula". Understanding the "whys" of the fallacy ...
Igor G's user avatar
  • 241
14 votes
Accepted

If a SARS-CoV-2 asymptomatic infected individual is exposed to a high viral load, could they develop COVID-19 disease?

What your government is proposing is a lot less than what was actually done in China. There, and perhaps that is still the case, large numbers of asymptomatic infected people were housed together in ...
Graham Chiu's user avatar
  • 13.3k
13 votes
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Father gets chickenpox, but doesn't infect his two children. How is this possible?

To add to @BryanKrause's answer re: rare events happen all the time, the children are not out of the woods yet. The mean incubation time for a primary VZV infection (the clinical syndrome known as ...
De Novo's user avatar
  • 3,178
12 votes
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What is the main way COVID-19 spreads?

The confusion exists because there are conflicting pronouncements from various authoritative sources but also conflicting pronouncements from the same authority. Covid-19 is a respiratory infection ...
Graham Chiu's user avatar
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9 votes

What are the limits on the amount of pathogens that a body can be immune to at any given time?

Won't this (having a flu vaccine every year) put them in an uncharted territory as far as effects on the immune systems are concerned within a couple of decades? No You are exposed to and develop a ...
De Novo's user avatar
  • 3,178
9 votes

2019 Novel Coronavirus (nCoV) lifetime outside an organism

Since it seems unlikely that these data are available already from the novel virus, I'll refer to other coronavirus strains associated with outbreaks, the SARS-CoV coronavirus associated with an ...
Bryan Krause's user avatar
  • 14.1k
9 votes

Can someone have an allergic reaction to a virus?

The TH1/TH2 model of T-cell responsiveness can be summarized as TH1 being the "antiviral/antibacterial" immune response and TH2 is the "antiparasite" immune response against worms ...
Bryan Krause's user avatar
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9 votes
Accepted

Has there been any medical studies as to whether drinking a 'Hot Toddy' can help to ward off or to help heal someone who has COVID-19?

To my knowledge no, nobody has specifically studied this in relation to COVID-19. I can't really prove the negative but I tried a few combinations of search terms in to PubMed and came up with nothing....
motosubatsu's user avatar
  • 1,291
9 votes

What determines whether an influenza virus causes the flu or a cold?

Is Influenza the disease simply a shorthand for a disease caused by an Influenza virus that happens to clinically present as worse than a cold? Pretty much. You have to bear in mind that until the ...
Charles E. Grant's user avatar
8 votes
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STI vs STD vs Sexually Transmitted Virus

Short Answer HIV is a virus and when the HIV virus has invaded the body it becomes an infection (specifically an STI only if and when transmitted through sexual contact). Whilst the terms STI and ...
Chris Rogers's user avatar
  • 6,195
8 votes

Father gets chickenpox, but doesn't infect his two children. How is this possible?

Apart from not getting infected due to pure chance (as mentioned already) there is one highly probable explanation (explanation, not overall chance). People get, but don't show it: asymptomatic ...
LаngLаngС's user avatar
  • 6,907
8 votes
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Will there ever be a universal vaccine for the common cold?

If I get infected once with the virus which causes a common cold, does that mean I will not get infected with the same strain of the virus ever in my lifetime? It depends on quirks of your immune ...
anongoodnurse's user avatar
8 votes

Why should/shouldn't one fear the long-term health effects of the Covid vaccines?

This general-audience article from Children's Hospital of Philadelphia gives a good overview of reasons to believe that long-term side effects are unlikely. To summarize its two main points: ...
BrenBarn's user avatar
  • 611
8 votes

What are the benefits of making animal viruses capable of infecting humans?

First off; to clear a couple of things up: Furin cleavage sites in coronaviruses are quite common - about 30-50% of human ones have them naturally1, and these sites do NOT necessarily cause them to ...
bob1's user avatar
  • 3,486
7 votes

I have natural immunity to Hepatitis B. Do I pose risk to others?

The Hepatitis B core antibody test is positive for IgG but negative for IgM indicating that you had the hepatitis B infection a while ago. The negative hepatitis B surface antigen test means that they ...
Graham Chiu's user avatar
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7 votes
Accepted

Does stopping fever hinder the process of killing bacteria via fever?

This is a great question, an area of active debate, and a personal interest of mine. I actually just did a presentation on this, so this answer will probably have more information in it than you need, ...
Nate's user avatar
  • 1,271
7 votes
Accepted

Can the Coronavirus be spread via public toilet seats?

The virus causing COVID-19 infects the respiratory tract. It is spread in droplets of moisture when an infected person sneezes, coughs, and exhales. These droplets can be inhaled directly and can also ...
Bryan Krause's user avatar
  • 14.1k
7 votes
Accepted

Is the washing hands in order to protect yourself from COVID-19 backed up by research?

Here's an article that I found helpful, to understand why washing hands with soap is so helpful, and how it helps (Pall Thordarson is a professor of chemistry at the University of New South Wales, ...
aparente001's user avatar
7 votes
Accepted

Are betadine mouthwashes really effective against COVID-19?

Are betadine mouthwashes really effective against COVID-19? In vitro (test tubes/culture plates) studies do show that providone iodine does kill viruses similar to SARS-CoV-2 after sufficient ...
anongoodnurse's user avatar
6 votes
Accepted

Could genetically modified viruses cure genetic diseases?

Yes. Gene therapy is an active area of research; most gene therapy approaches that are studied use some sort of viral vector, those that don't are more the exception and it is unclear how several of ...
Bryan Krause's user avatar
  • 14.1k
6 votes

If I get COVID-19, can I get cured by myself?

If you’re young and healthy with only mild symptoms, your doctor will likely advise you to isolate yourself at home and to limit contact with others in your household. You’ll likely be advised to rest,...
Bryan Krause's user avatar
  • 14.1k
6 votes
Accepted

How do we know that the Spanish flu was an influenza?

Because we know its genomic sequence. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2720273/: Using fixed and frozen lung tissue of 1918 influenza victims, the complete genomic sequence of the 1918 ...
Franck Dernoncourt's user avatar
6 votes
Accepted

Could the COVID-19 vaccine adversely impact healthy protein reception?

You say: I can't find any evidence or articles that specifically confirm that our immune system won't start targeting healthy ligands, such as hormones, other proteins, or even pharmaceutical drugs ...
the gods from engineering's user avatar
6 votes
Accepted

Is the code from the mRNA vaccine executed by the cells as a one-off?

Basically neither of your hypotheses is correct. A piece of mRNA isn't usually destroyed after one transcription. Nor does it create an "infinite loop" in the cell. Instead there's a balance ...
the gods from engineering's user avatar
5 votes
Accepted

Dengue fever carrier

The virus transmits not person-to-person, but person-to-mosquito-to-person. The carriers may be bitten by mosquitos who up until that point weren't infecting people, and afterwards can. The World ...
Kate Gregory's user avatar
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