Question: when was the first virus found in both plants and animals

title: Virus
text: Louis Pasteur was unable to find a causative agent for rabies and speculated about a pathogen too small to be detected using a microscope . In 1884 , the French microbiologist Charles Chamberland invented a filter ( known today as the Chamberland filter or the Pasteur - Chamberland filter ) with pores smaller than bacteria . Thus , he could pass a solution containing bacteria through the filter and completely remove them . In 1892 , the Russian biologist Dmitri Ivanovsky used this filter to study what is now known as the tobacco mosaic virus . His experiments showed that crushed leaf extracts from infected tobacco plants remain infectious after filtration . Ivanovsky suggested the infection might be caused by a toxin produced by bacteria , but did not pursue the idea . At the time it was thought that all infectious agents could be retained by filters and grown on a nutrient medium -- this was part of the germ theory of disease . In 1898 , the Dutch microbiologist Martinus Beijerinck repeated the experiments and became convinced that the filtered solution contained a new form of infectious agent . He observed that the agent multiplied only in cells that were dividing , but as his experiments did not show that it was made of particles , he called it a contagium vivum fluidum ( soluble living germ ) and re-introduced the word virus . Beijerinck maintained that viruses were liquid in nature , a theory later discredited by Wendell Stanley , who proved they were particulate . In the same year Friedrich Loeffler and Paul Frosch passed the first animal virus -- agent of foot - and - mouth disease ( aphthovirus ) -- through a similar filter . 

Answer: answer: In 1892, the Russian biologist Dmitri Ivanovsky used filter to study what is now known as the tobacco mosaic virus, crushed leaf extracts from infected tobacco plants remain infectious after filtration. In 1898, Friedrich Loeffler and Paul Frosch passed the first animal virus -- agent of foot - and - mouth disease ( aphthovirus ).
answer: The first virus found in plants was in 1898 when Martinus Beijerinck became convinced that the filtered solution contained a new form of infectious agent after he repeated the experiments Dmitri Ivanovsky started by using Charles Chamberland's filter to study what is now known as the tobacco mosaic virus.
In 1898 as well, Friedrich Loeffler and Paul Frosch passed aphthovirus, which was the first animal virus.