Questions tagged [virology]

Virology deals with the study of viruses, infectious entities that require the machinery of a host cell to replicate.

Filter by
Sorted by
Tagged with
94
votes
6answers
21k views

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

Typically, people call viruses some kind of organic compounds that cannot reproduce autonomously and which lower the fitness of their hosts. Even the word "virus" means "venom" in Latin. But from the ...
48
votes
7answers
9k views

Why isn't a virus “alive”?

The recent news about a new supermassive virus being discovered got me thinking about how we define viruses as non-living organisms whilst they are bigger than bacteria, and much more complex than we ...
38
votes
2answers
42k views

Why don't we develop immunity against common cold?

We all suffer from common cold, and that, frequently. Why have we not developed immunity against it till now? By immunity I mean immunity as a species.
32
votes
2answers
3k views

Why doesn't blood remain on a mosquito's proboscis in quantities that could spread blood-borne diseases?

We know that HIV can't be transmitted by mosquitos, and nor can other highly virulent viruses that are transmitted through blood and bodily fluid exchanges, such as Ebola (thankfully!). Marcus Junius ...
30
votes
1answer
1k views

How did viruses come to be?

My question is out of curiosity and got me thinking. How did viruses with the head, tail and tail fibres actually evolve? These viruses look more like machines than biological entities. Are there any ...
28
votes
3answers
8k views

Can the dead be brought back to life by viruses?

Zombies have been a part of popular culture for decades. The living dead rising up to take over the world is a terrifying concept, worthy of Hollywood blockbusters and television hits. Some of those ...
28
votes
2answers
6k views

Why is rabies incurable?

I'm still not sure about the mechanics that lead to rabies being incurable. I know that it can be treated before any symptoms show up, but why is it that once symptoms show the person is a dead man ...
26
votes
3answers
6k views

Did the Zika virus mutate?

The Zika virus was already present and known to the world (mostly in Southeast Asia) before the current outbreak. Why has the virus caused such an extreme outbreak? Has it mutated from its ...
24
votes
1answer
4k views

How did scientists discover HIV?

Imagining that we're now in 1983 (when HIV was discovered), there were no modern machines at that time to sequence massive genome extracted from blood. There was a strange disease and no one know what ...
23
votes
2answers
12k views

Is it known how the first viruses formed?

The oldest known virus is known to have infected prehistoric insects 300 million years ago. A virus is basically a parasitic strand if DNA or RNA encapsulated in a protein coat. It enters cells by "...
23
votes
2answers
4k views

Harmless virus?

Is it possible for a virus to live symbiotically with its host? Is the human body plagued with viral infections that do negligible harm, or even serve a beneficial role?
21
votes
2answers
4k views

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

People can be vaccinated against certain diseases. Principle of vaccination is to use live attenuated load or inactivated. My question is - why we dont have vaccination against all diseases which are ...
21
votes
2answers
2k views

Could viruses be used as antibiotics?

Could we use viruses that only affect bacteria to act as antibiotics? The more bacteria, the more times the virus divides, so the stronger it gets. Is this practical?
20
votes
2answers
2k views

Can Biologists identify all viruses?

I went to the doctor today with my girlfriend, and the doctor said that she had a virus but doesn't know which one and she should let the infection heal with some rest. The fact that the doctor didn'...
20
votes
4answers
4k views

How to understand influenza strain designations?

What do the strain designations for flu mean? For example avian flu is classified as H5N1, what do the letters H, ...
19
votes
3answers
11k views

What causes a 'stuffy' or 'runny' nose when you have a cold?

When humans get the common cold, a common symptom is a stuffy or runny nose. Is that the body's immune response or is that the virus's doing?
17
votes
2answers
553 views

Why do people dying of immune deficiency diseases appear sick?

Please forgive the obviously silly appearance of this question, and/or of the tenor which may come across as flippant or dismissive of real world suffering. My intention is none of the above. As a ...
17
votes
1answer
2k views

Why are there 2 copies of RNA in the HIV virion?

There are two copies of the RNA in the HIV virion. These are retroviruses. So, they can make cDNA from even just one copy using reverse transcriptase. What is the use of the other? Are both ...
16
votes
2answers
6k views

For how long would a flu-contaminated parcel be an effective disease vector?

A parcel has been delivered and contaminated by a person who has the flu. For how long would the parcel be an effective disease vector?
16
votes
5answers
2k views

Why have parasites not evolved to be harmless?

I have yet to understand why so many viruses or bacteria haven't evolved to be harmless (specifically, I don't know of any harmless virus). I think it would be greatly beneficial for a virus to ...
16
votes
1answer
628 views

How does herpes (HSV) infection suppress HIV?

HIV compromises the human body to defend against infection. Yet people who are infected with herpes are at less risk of developing AIDS. How does this work?
15
votes
2answers
7k views

Why does immunity from the flu vaccine appear only after two weeks?

It is said that immunity from a flu vaccine appears after about two weeks. However, from experience, the flu usually lasts only a few days. If sufficient antibodies appear only after two weeks ...
15
votes
1answer
2k views

What do viruses do during incubation period?

For example, there is an incubation period of around 1 to 3 days for common cold, and that of AIDS can range over to decades. What do viruses do actually do during the incubation period? What ...
15
votes
2answers
51k views

Why does rabies cause hydrophobia?

What feature of rabies pathophysiology causes hydrophobia? Why is hydrophobia unique to this one particular type of viral infection?
15
votes
2answers
593 views

What is the contribution of viruses to the evolution of mankind?

I'm interested in horizontal gene transfer in bacteria, viruses, and organisms such as Bdelloid Rotifers. I've just read in Carl Zimmer's 'A Planet of Viruses' the following passage: As a host cell ...
14
votes
2answers
4k views

How are viruses weakened to be suitable for vaccination?

I understand there are two kinds of active vaccination Injecting complete viruses that are weakened to not cause the disease being vaccinated against Injecting only antigen particles of viruses that ...
14
votes
4answers
647 views

Computer Virus that infects DNA?

I have watched a talk by Mikko Hypponen (CEO of the security company F-Secure) called Silicon Plague. There, roughly at minute 51 of the talk, he mentions a computer code that is supposed to be able ...
14
votes
1answer
1k views

How heavy are all foreign microorganisms in and on the human body?

I define "foreign microorganism" as a microorganism which is not produced by the human body (not antibodies or leukocytes) including bacteria, viruses, fungi, biofilm aggregates or small lifeforms ...
13
votes
4answers
4k views

Can viruses be toxic?

Bacteria can produce toxins like endotoxins and exotoxins. In diseases like cholera or tetanus they can harm infected people due to these toxins. Now, although viruses are much smaller and are ...
13
votes
1answer
1k views

Why are people unable to develop lasting immunity against Norovirus?

Infection with many viruses will result in decades-long if not lifetime immunity, for example chicken pox. Because of the large number of viruses responsible for the common cold, lifelong immunity to ...
12
votes
2answers
253 views

Are there viruses that affect cells across different species?

I'm not a professional in biology nor a student, but I'm curious about this. To be more specific: why doesn't a plant virus affect animal cells? I suspect that different kinds of cells have different ...
11
votes
2answers
2k views

How long does the Ebola virus remain infectious on contaminated items or surfaces?

I'm sure there will be variation depending on what the contaminated item or surface is made of - linens, I could imagine, would remain dangerous for longer than a door-knob. But if the items are not ...
11
votes
4answers
198 views

Is there a period after you have had a cold when you cannot get a cold again?

I always assumed colds ran on a 'no tagbacks' principle: once it's out of your system, it takes a while before you can get a cold again. Is there any truth to this, or can rhinoviruses hit you at any ...
11
votes
3answers
10k views

Is there any virus that contains both DNA and RNA in its genome?

It is known that viruses contain DNA or RNA- either one and not both. I came across a question: Which virus contains both DNA and RNA?
11
votes
1answer
142 views

Are homozygous carriers of the CCR5-Δ32 allele fully immune to all known strains of HIV?

Or is there documented evidence of even one homozygous carrier contracting HIV and staying infected?
10
votes
5answers
3k views

Is there an 'anti-virus'?

A virus spreads around and usually attaches itself to the host, multiplies & causes diseases. But is there something like an anti-virus? A single celled entity that does the opposite: spreads ...
10
votes
1answer
256 views

What determines when a virus becomes a “new strain”?

The reason we cannot find a cure for the common cold is because viruses mutate rapidly. Where do the mutations occur in the DNA/mRNA of viruses and does this have any effect on the protein level? what ...
10
votes
1answer
193 views

What is the difference between influenza A and B viruses that causes their distinct seasonal patterns?

I recently learned from an answer at health.SE* that influenza B tends to occur later in the season compared to influenza A. According to the graph in that answer, during this year’s flu season the ...
9
votes
2answers
9k views

Why do I need a flu shot every year, while many other vaccinations last years or even a lifetime?

Is it a viral vs. bacterial thing? Is there just more variety among types of flu than other diseases, so that this year's vaccines don't cover next year's flu?
9
votes
2answers
2k views

To what extent is Ebola airborne? (aerosols)

Recently, CIDRAP at the University of Minnesota announced that Ebola may be more transmissible through aerosols than previously thought. I lack the familiarity with the field to critically evaluate ...
9
votes
2answers
13k views

What is the life cycle of a wart?

There doesn't seem to be a lot of information available on research done on warts. What is the life cycle of a wart? How does it spread? -- specifically how does it recruit cells to spread it? What ...
9
votes
2answers
2k views

Are viruses self-propelled?

So obviously, viruses are nonliving. But when my teacher was teaching viruses in the video (we're doing "flip" learning this semester), the way he described it, it seemed like the viruses responded to ...
9
votes
2answers
171 views

Virus that can enter all cell types

As I understand, each virus type can enter a particular cell type. For example HIV can enter CD4 & CD8 cells, while HBV can enter liver cells, some other viruses can enter other cell types like ...