Viruses: a virus is a minute microorganism too small to be seen under an ordinary microscope. It is much smaller than bacteria, so tiny that they cannot even be seen through an ordinary microscope but require a special apparatus, the electron microscope. Thus, it was not discovered until sometime later than most bacteria.
Another reason they are harder to study is that, unlike bacteria, they are extremely fussy about where they grow, normally refusing to have anything to do with laboratory “food”. With the greatest of difficulty, the scientist have succeeded in working out ways of getting them to grow anywhere except in an animal body. Fussy as they are, they are extremely potent; very small numbers can start a disease. Since 1900, many diseases, such as smallpox, common cold, poliomyelitis, yellow fever, influenza, infectious hepatitis, rabies, chicken pox, measles, mumps, and other contagious diseases, have been found to be caused by filtrable viruses.Continue reading “Community Health and Welfare- Infection- Microbe Invasion- Pathogens – Viruses/ All About Nursing”