VIRUSES AND ANTIVIRAL AGENTS-BRIEF

Viruses are infectious agents without having their own cell wall or nucleous but replicate the cell content of the host as their own and convert  them convenient for their life.A virus infected cell’s physiology would be totally changed and It itself behave against its own tissue and spread rapidly to infect other cells.Hence eradicating virus is so difficult and is not as easy as bacteria

Virus can infect all form of life including animals, plants,microbiots including bacteriae.Although there are million types of viruses are known only a few(5000 types) have been known in detail.

VIRIONS are viral patricles before invading or infecting a cell of an organism packed into helical or icosahedral shaped particles with three parts as follows:-

1)The genetic material made from DNA or RNA;

2)A proein coat known as Capsid which sorrounds and protect the genetic material

3)And in some cases a lipid coat surrounding the capsid when they are outside

A cell.

Readers also visit to http://pharmamedilatest.blogspot.com for more about bacterial infections and a full pharmacology of Antibiotics.This website http://www.pharmamedilatest.blogspot.com is exclusively for Allergic medication both viral and non viral but still both sites are not yet completed.You visit regularly for periodic updates for completion

Visit to http://www.pharmalatest.blogspot.com for a full basic knowledge about Diabetes Mellitus,and Non Steroidal Anti-Inflammatory Drugs including Paracetamol

                                

The Common Cold:-The viruses most commonly responsible for the common cold are rhinoviruses (about 40% of the cases) followed by coronaviruses

In order to produce cold the virus  must penetrate the mucus that covers  the nasal epithelium

Mucus in the nasal passages rap and remove most contaminants but he rhinovirus  maintains it’s attachment with the mucus membranes of the nose by a specific receptor.

Rhinovirus infections eventually leads to the release of various inflammatory secretions like prostaglandins,leucotrienes,and kinins which are causing the symptoms of cold such as nasal congestion,runny nose and sore throat.

It is to be noted that Histamin the allergy producing hormone is not involved to produce inflammatory effect in rhinoviral infection but it is associated with allergic responses such as sneezing and itching.

Scientiss believe that common cold is caused by 200 and more type of virus each time body devolops life time immunity as the age is getting older and older and hence people at the old age will get a fewer attack of the cold compared with children because of their acquired longtime or life time immunity.

Pathogenesis

1.Cold can be transmitted as we can easily assume by the mist produced by sneezing and most perfectly by shaking hand with a cold sufferer who has recently blown off his nose

2.On the skin,certain fabrics and hard non-porous meterials such as sainless steel and wood,self inoculation occurs readily.These viruses can survive 3 to 4 hours outside the body.For instance a susceptible person touches the virus from a contaminated surface and rub his eyes or nose transfer the virus to the nasal mucus membrane a convenient spot for the virus to live

3.Shaking hands,opening a door,touching a toy,and rubbing noses are he more frequent routes han coughing,sneezing and kissing etc.cold viruses can survive in saliva and kissing can spread the virus from one to another.

4.The probability of infection is more by shaking hands of a contaminated person

To Avoid:a)Keep hands away from the nose;b)Frequently wash hands by detergent and hot waer;c)Blow the nose with disposable paper;d)Cover a cough or sneeze.

SYMPTOMS:1.Symptoms begin slowly usually one or two days after the infection;

2)At first a scratchy sore throat with runny nose itchy eyes and tiredness.The secretions of the ,nose and throat increase followed by cough.

3)Then the secretions of the throat and bronchial tree slowly gets thickened to give difficult expectoration.This peak symptoms would usually for 5 days and decline and finally will disappear completely after 10 to 15 days.

TREATMENTS

Decongesants Nasal decongestants are usually alpha adrenergic stimulants and thereby they constrict the blood vessels and eventually minimise the blood circulation in the lungs and minimise the edema in the alveoli and decongest it.

Excess nose blow will further enhance the rouble by pushing the fluid ino he nasal sinuses and the ear Eustachian tubes.So better avoid this to he maximum.

Nasal Decongestants are inducing local vasoconstrictions and thereby relieve the congestion but the disadvantage is frequent uses such as morethan 7-8 days of these agents may lead to rebound decongestion. (e.g):-1.Ephedrine,2.Naphazolin3.Phenylephrine  etc.etc since detail of these medicines are irrelevant to the title of this article hence we will go further regarding to this agents in future under another title later on

Some Common Anti-Viral Agents:-

Mostly anti viral agents resembles nucleic acids similar to viral structure to cheat and kill the viruses e.g.zidovudin,ganciclovir,vidarabin,and acyclovir