107
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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 ...
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79
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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 ...
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59
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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 ...
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55
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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 ...
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54
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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, ...
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53
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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 ...
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52
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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) ...
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49
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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, ...
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47
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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 (...
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44
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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 ...
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43
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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 ...
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41
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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 ...
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40
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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 ...
- 3,214
38
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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&...
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37
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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 ...
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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 — ...
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37
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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): ...
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36
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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 ...
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35
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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/...
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33
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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 ...
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32
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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 ...
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31
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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
...
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31
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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 ...
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29
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 ...
- 5,590
29
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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 ...
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29
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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 ...
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28
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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" ...
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27
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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 ...
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25
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For how long would a flu-contaminated parcel be an effective disease vector?
How long should I wait before handling the parcel to avoid contracting the virus?
If you use gloves, or don't touch your face and just wash your hands after opening, you don't have to wait at all. ...
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How does a Coronavirus "test kit" work?
There are actually 3+ types of test kits widely used to diagnose diseases caused by viruses. We can check for the nucleic acid of the virus, the antigen of the virus that would cause an immune ...
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