106 votes
Accepted

What's the evidence against SARS-CoV-2 being engineered by humans?

At the moment, there is very little scientific literature about this, but I found two papers that address the problem and are fairly easy to understand. You can find them in the references. Reference ...
Chris's user avatar
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79 votes
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Do beneficial viruses exist? If so, what examples are there?

Do they exist? Yes What are they called? Marilyn Roossinck calls them viral mutualistic symbiotes. She has an excellent review here. What are some examples? My personal favorite is GB-Virus C, or ...
De Novo's user avatar
  • 8,751
71 votes

Can the dead be brought back to life by viruses?

You must tell facts from fiction; viruses need living cells to replicate because they do not have the molecular machinery at hand to generate energy and construct building blocks essential to life. So ...
AliceD's user avatar
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59 votes
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Are the social-distancing measures implemented against SARS-CoV-2 also suppressing the spread of other viruses?

Yes, this helps as well with other infectious diseases. A good example is the flu, which season was measurably shorter this year than in other years on record. See the figure from the reference 1 for ...
Chris's user avatar
  • 51.3k
55 votes

Virus cannot survive on surface after certain time period, but why and how?

Many important viruses are coated with a lipid envelope and rely on this to enter the host cell. This envelope is fragile - it's similar to a soap bubble - and it can be disrupted in many ways. Lipids ...
timeskull's user avatar
  • 3,666
54 votes

How do mutations of viruses lead to drug resistance?

It doesn't. Viruses don't "know" anything. Mutations occur at random. Most of them don't do anything, or have a slight negative effect on the ability of the virus to infect and reproduce. However, ...
Charles E. Grant's user avatar
53 votes

Why does vaccine development take so long?

Roni Saiba's answer does a good job of explaining what goes into current vaccine development and why it takes so much effort, but I want to directly address the question of why we can't just grow some ...
timeskull's user avatar
  • 3,666
52 votes
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How does a Coronavirus "test kit" work?

The CDC has made available online its nCoV test kit. Briefly,the kit contains primers and probes for real-time reverse-transcriptase PCR, as well as instructions for appropriate use and (critically) ...
iayork's user avatar
  • 14.2k
49 votes

Why do some viruses cease being a problem even though no vaccine or cure is found?

Infections spread in a population when the number of new infections caused by an infected person is greater than or equal to 1. If each infected person spreads the virus to less than 1 person, ...
Bryan Krause's user avatar
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47 votes
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Is the Common Cold an Immune Overreaction?

Can someone die of the common cold? No. The common cold is a clinical syndrome restricted to upper respiratory tract involvement. By clinical syndrome, I mean it is the constellation of symptoms (...
De Novo's user avatar
  • 8,751
43 votes
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Does the genetic sequence of SARS-CoV-2 end with 33 A's?

This is a poly(A) tail, which is a feature found in the majority of eukaryotic RNAs (especially mRNA) and is also not uncommon in RNA viruses (which essentially mimic endogenous mRNA for their own ...
canadianer's user avatar
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43 votes
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How many times has SARS-CoV-2 mutated?

This question makes a number of incorrect assumptions and I don't have time to correct them. The short answer is that the virus has mutated probably hundreds of times since it entered humans in late ...
iayork's user avatar
  • 14.2k
41 votes

Are the social-distancing measures implemented against SARS-CoV-2 also suppressing the spread of other viruses?

In addition to Chris' answer above, the effect is even more pronounced in Southern Hemisphere countries where flu season started during the pandemic. The New Zealand lockdown and health response ...
Aethernaught's user avatar
40 votes

Why does vaccine development take so long?

While the existing answers are great and cover a lot of the difficulties in vaccine development, I feel that they fail to address (or at least sufficiently emphasize) the fundamental misconception at ...
Ilmari Karonen's user avatar
39 votes

Killing enveloped viruses with soap

Soap molecules are amphiphilic. This means those molecules have parts which are hydrophilic (water-loving, or "polar") and parts which are hydrophobic (water-avoiding, or "non-polar&...
Alex Reynolds's user avatar
37 votes

Do viruses or bacteria have a flavour?

So I think this is a more conversational kind of question. I will address some misconceptions you have, and I will try to keep it brief, considering the nature and depth of your question. One could ...
S Pr's user avatar
  • 6,182
37 votes
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Why don't viruses cause wounds?

A virus does not destroy that many cells before it is exterminated by the immune system or before the host dies. Perhaps even more crucially, viruses typically target a very specific type of cell — ...
Roger Vadim's user avatar
  • 3,822
37 votes

Why don't viruses reach broad concentration outdoors in a city like allergens?

2, 4, 5, and 6. 6 being that the UV light (from the sun), fluctuations in temperature, humidity, wind etc mean that the virions are decayed relatively rapidly for most virus species. To address (1): ...
bob1's user avatar
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36 votes
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Can Biologists identify all viruses?

Do physicians/biologists not know all the different types of viruses out there? No, Biologists don't know all the viruses that exist out there. There's a lot! We do know many of the ones infecting ...
YviDe's user avatar
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36 votes
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Do viruses or bacteria have a flavour?

As you could imagine, a systematic cataloguing of bacterial or viral flavor profiles would violate a number of biosafety protocols. However, in a laboratory setting, different bacteria definitely have ...
MikeyC's user avatar
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35 votes
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Are all emerging viral diseases of the past 100 years zoonoses?

To my knowledge, yes. A partial list of recently emerged/emerging viral diseases (I certainly could have missed some), with probable reservoir hosts: Chikungunya* (birds, rodents) coronaviruses/...
Ben Bolker's user avatar
  • 5,324
33 votes
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How did scientists discover HIV?

HIV was identified as an infectious disease through classical epidemiology, and the virus was identified through classical virology. I won't get into the epidemiology, but briefly it went pretty much ...
iayork's user avatar
  • 14.2k
33 votes
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Why is China experiencing such a surge in acute cases of COVID?

There are a number of different reasons, all adding up to the current situation. The strain: There is not a special strain going on in China, according to different references it is mostly the ...
Chris's user avatar
  • 51.3k
32 votes

Why don't we have vaccination against all diseases caused by microbes?

Mainly cost/benefit analysis. Using vaccines has a cost, both in dollars and in risk. That cost may be very low (cheap safe vaccines, like measles vaccine), or may be relatively high (smallpox vaccine ...
iayork's user avatar
  • 14.2k
30 votes
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What does vaccine efficacy mean?

Vaccine efficacy Pfizer's target measures for efficacy (see the study on clinicaltrials.gov) seem to be: Confirmed COVID-19 in Phase 2/3 participants without evidence of infection before vaccination ...
Bryan Krause's user avatar
  • 42.8k
29 votes

Why are more children being hospitalized with Covid-19?

Right now, at least, it's not clear whether anything significant has changed biologically for children with respect to the Delta variant. What is known for certain, however, is that Delta is very ...
jakebeal's user avatar
  • 6,977
29 votes

Are fully vaccinated people more likely to not get infected at all with COVID-19?

Yes, this is the effect of the vaccine. A reduction of infections of over 88%, a reduction of severe cases and death by 95% and higher. See reference 1 for the details. Data from the ReCoVAM Study ...
Chris's user avatar
  • 51.3k
28 votes

Virus cannot survive on surface after certain time period, but why and how?

Ultraviolet (UV) light emitted from the sun has enough energy to break chemical bonds in DNA and RNA. Some frequencies of UV light can cause damage in the DNA in skin cells that can lead to ...
Alex Reynolds's user avatar
27 votes

Do beneficial viruses exist? If so, what examples are there?

Another good virus would be a Bacteriophage, a virus that infects and kills illness-causing bacteria. From Wiki: A bacteriophage also known informally as a phage, is a virus that infects and ...
Astor Florida's user avatar
27 votes
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Isolation of viruses and Koch's Postulates in connection with terrain theory and claims that viruses don't exist

It is very easy to disprove their claims, but the burden of proof doesn't lie with you, it lies with the person making the claim. If they want to claim that there is a "cell waste product" ...
bob1's user avatar
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Only top scored, non community-wiki answers of a minimum length are eligible