ഗവ.മോഡൽ എച്ച്. എസ്.എസ്. കരുനാഗപ്പള്ളി/അക്ഷരവൃക്ഷം/VIRUS

VIRUS A virus is a submicroscopic infectious agent that replicates only inside the cells of an organism and inactive outside the cell. Virus can infected all life forms from animals and plants to microorganisms including bacteria, etc. Dimitry Ivanosky in 1892 first describes a non bacterial pathogen infected in a tobacco plant and the discovery of tobacco mosaic virus by Martinus Beijerink in 1898. He named the pathogen as virus. The word virus came from latin which means poison. The definition of virus in 1728, long before the discovery of Ivanosky, was the agent cause infectious disease. Viruses are formed whenever there is life and has existed since living cells first evolved. The origin of virus is unclear because they do not form fossil. Virus displays a wide diversity in size, shape, etc. this is called as ‘morphologies’. Virus is smaller than bacteria. Most viruses that have been studied yet have diameter between 20-300nm. Most viruses cannot be seen through an optical microscope. So scanning and transmission through an electron microscope is used to visualize them. International committee on taxonomy is formed by Lwolf Home. classification system of viruses are as follows. Realm - viri sub realm - vir phylum - viricota sub phylum - viricotina class - viricetes order - virales suborder - viriniae family - viridae sub family - virinae genus - virus subgenus - virus Common human diseases like common cold, chickenpox and serious diseases such as ebola, aids, etc. are caused by virus. Viral epidemiology is a branch of science that deals with the transmission and control of virus infection in humans. There is two types of transmission- vertical and horizontal. Vertical transmission means mother to children spreading. Eg: Hepatitis B, HIV Horizontal transmission means people to people transmission. Eg: Hepatitis C, Covid-19. Epidemiology is used to break the chain of infection in population during out break of virus. Epidemics and Pandemics Epidemics is the term that is often broadly used to describe any problem that has grown out of control. An epidemic is defined as ‘an out break of disease that occur over a wide geographic area and affect an exceptionally high proportion of the population.’ The term pandemic refers to geographical spread and is used to describe a disease that affects the whole country or the entire. ‘On March 11, 2020 World Health Organisation (WHO) characterised the new corona virus (covid 19) as a pandemic’ . Prevention Certain viruses and bacteria are transmitted through close contact between people. Several situations like, • living or working with other people • sharing items • giving care to a person • frequenting public area Measures to take • Always keep your hands clean • Coughing and sneezing without contaminating • Avoid touching nose, eyes and mouth with unwashed hands. These are the entry sites for viruses. • Avoid contact with infected people • Clean your surroundings regularly നന്ദന പി ജെ. 8 D ഗവ.മോഡൽ എച്ച് എസ്സ് എസ്സ് കരുനാഗപ്പള്ളി കരുനാഗപ്പള്ളി ഉപജില്ല കൊല്ലം അക്ഷരവൃക്ഷം പദ്ധതി, 2020 ലേഖനം  സാങ്കേതിക പരിശോധന - mtjose തീയ്യതി: 20/ 04/ 2020 >> രചനാവിഭാഗം - ലേഖനം