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How Does The Immune System React Against Viruses?
Question: How does your immune system work on viruses?
Brief Answer:
Read below.
Detailed Answer:
Hello! I will try to answer your question in an understandable way.
Viruses are organisms which invade the body cells in order to live and replicate.
The first step of the immune system fight is before the virus enters the cell through antibodies, which bind the virus rendering it inactive and then are detected by immune cells like phagocytes which envelop and destroy the virus.
If that doesn't work once the virus enter a host cell, the cell itself can not kill it, but it tries to let immune system know that it is infected so it can react. It does that by displaying some special proteins on the cell surface, proteins which are specific for this case (called MHC class I- class I major histocompatibility complex proteins).
The immune system can react through different ways. Most common one is through lymphocytes of the T type. They detect the cells displaying these special proteins and kill them which is necessary to prevent the virus from multiplying and spreading further.
Another way is through a part of the immune system called natural killer (NK) cells. Some viruses slow down production of MHC proteins and T cells can not detect them, so these NK cells are able to detect even smaller amounts of MHC and destroy the cells anyway.
Of course I have tried to keep things simple with only the major players, there are several other components of the immune system in play, it's much more intricate. Also the above mechanism is in an ideal world, but many viruses have mechanisms to escape these immune system responses, hence we get sick at times.
I remain at your disposal for other questions.
Read below.
Detailed Answer:
Hello! I will try to answer your question in an understandable way.
Viruses are organisms which invade the body cells in order to live and replicate.
The first step of the immune system fight is before the virus enters the cell through antibodies, which bind the virus rendering it inactive and then are detected by immune cells like phagocytes which envelop and destroy the virus.
If that doesn't work once the virus enter a host cell, the cell itself can not kill it, but it tries to let immune system know that it is infected so it can react. It does that by displaying some special proteins on the cell surface, proteins which are specific for this case (called MHC class I- class I major histocompatibility complex proteins).
The immune system can react through different ways. Most common one is through lymphocytes of the T type. They detect the cells displaying these special proteins and kill them which is necessary to prevent the virus from multiplying and spreading further.
Another way is through a part of the immune system called natural killer (NK) cells. Some viruses slow down production of MHC proteins and T cells can not detect them, so these NK cells are able to detect even smaller amounts of MHC and destroy the cells anyway.
Of course I have tried to keep things simple with only the major players, there are several other components of the immune system in play, it's much more intricate. Also the above mechanism is in an ideal world, but many viruses have mechanisms to escape these immune system responses, hence we get sick at times.
I remain at your disposal for other questions.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
So it is Easy to understand clearly that it's definitely hard sometimes when it's necessary to hospitalize someone due to an illness that may require a couple of other Doctor consultation to help him.... Because it is NOT any longer within his control ?? Or is it for other reasons??
Brief Answer:
Read below.
Detailed Answer:
I am sorry for not being able to answer a little earlier.
Reading and rereading your last question though I am afraid I am not sure what do you mean exactly. Are you asking why a doctor ask for a couple of other doctor's advice. If that is the case, then nothing wrong with that, medicine is developing into more and more subspecialties all the time and it is natural to ask for the help of another specialist when it is a case with elements belonging to another specialty.
However as I said I am not sure what you meant by your question, please try to explain it a little more, giving some more detail.
Looking forward to hearing from you again.
Read below.
Detailed Answer:
I am sorry for not being able to answer a little earlier.
Reading and rereading your last question though I am afraid I am not sure what do you mean exactly. Are you asking why a doctor ask for a couple of other doctor's advice. If that is the case, then nothing wrong with that, medicine is developing into more and more subspecialties all the time and it is natural to ask for the help of another specialist when it is a case with elements belonging to another specialty.
However as I said I am not sure what you meant by your question, please try to explain it a little more, giving some more detail.
Looking forward to hearing from you again.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
yes that's what I was asking.. accept I was asking why for a virus they prescribed I.v medications when they could be prescribing oral.... is it necessary to hospitalize someone for that?
Brief Answer:
Read below,
Detailed Answer:
It depends what type of virus. There are some common virus infections which as you say do not require hospitalization, only plenty of fluid and oral medication.
There are cases though when the infection may be threatening and more aggressive management is needed, with intravenous antivirals, like encephalitis (brain infection) for example.
At times the signs may not be clear and the doctor may prefer to keep the patient under observation for a few days to confirm the diagnosis, when he suspects involvement of other body systems can call for help of other specialists as well. Other times the patients may have many other associated conditions and the doctor may prefer to hospitalize the patient for the fear of complications happening.
So these decisions are according to each patient's individual characteristics.
I hope to have been of help.
Read below,
Detailed Answer:
It depends what type of virus. There are some common virus infections which as you say do not require hospitalization, only plenty of fluid and oral medication.
There are cases though when the infection may be threatening and more aggressive management is needed, with intravenous antivirals, like encephalitis (brain infection) for example.
At times the signs may not be clear and the doctor may prefer to keep the patient under observation for a few days to confirm the diagnosis, when he suspects involvement of other body systems can call for help of other specialists as well. Other times the patients may have many other associated conditions and the doctor may prefer to hospitalize the patient for the fear of complications happening.
So these decisions are according to each patient's individual characteristics.
I hope to have been of help.
Note: Get 1 to 1 help with your critical health concerns.Click here..
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
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