Life Cycle of Common Cold?!


Question:

Life Cycle of Common Cold?

What is the general life cycle of the common cold. Im curious to know how it begins, is discovered by the body, fought and then finally destroyed.

Also if possible id be interested to know about symptons related to its different stages. For example today my nose has begun to run with a darker shade of mucus.


Answers:

Most common colds are caused by infection by rhinovirus. Other viruses causing colds are coronavirus, human parainfluenza viruses, or human respiratory syncytial virus.

Mechanism of infection
A cold virus can infect the next person before it is defeated by the body's immune system. Sneezes expel a significantly larger concentration of virus "cloud" than coughing. The "cloud" is partly invisible and falls at a rate slow enough to last for hours—with part of the droplet nuclei evaporating and leaving much smaller and invisible "droplet nuclei" in the air. Droplets from turbulent sneezing or coughing or hand contact also can last for hours on surfaces, although less virus can be recovered from porous surfaces such as wood or paper towel than non-porous surfaces such as a metal bar. The incubation period (time between becoming infected and developing symptoms) is one to three days.The infectious period (time during which an infected person can infect others) begins about one day before symptoms begin, and continues for the first five days of the illness.[3] Symptoms, however, are not necessary for viral shedding or transmission, as a percentage of asymptomatic subjects exhibit viruses in nasal swabs, likely controlling the virus at concentrations too low for them to have symptoms.

The virus enters the cells of the lining of the nasopharynx (the area between the nose and throat), and rapidly multiplies. The major entry point is normally the nose, but can also be the eyes (in this case drainage into the nasopharynx would occur through the Nasolacrimal duct).

Symptoms usually begin within 2 to 3 days after infection. The first indication of a cold is often a sore or scratchy throat. Other common symptoms are runny nose or congestion, sneezing and cough. These are sometimes accompanied by muscle aches, fatigue, and weakness. Colds rarely cause fever or headache, and never lead to extreme exhaustion. (These latter symptoms are more usual in influenza, and can differentiate the two infections.) The symptoms of a cold usually resolve after about one week, but can last up to 14 days, with a cough lasting longer than other symptoms. Symptoms may be more severe in infants and young children, and may include fever.[4][5][6]

Between one-third and one-half of all people exposed to a cold virus become infected;[7] 75% of the infected population show symptoms, which start 1–2 days after infection.

After a common cold, a sufferer develops immunity to the particular virus. This immunity offers only limited protection against the many other cold viruses. The person, therefore, can easily be infected by a different cold virus.

Well there's no stage in common cold. What you've been experianced is called secondary infection.
I don't really understand about what you mean by "life cycle" : d'ya rever to mecanism of infection or pathogenesis ?
Anyway, you can simply read what you want to know at :




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