Search results
Results from the WOW.Com Content Network
In epidemiology, force of infection (denoted ) is the rate at which susceptible individuals acquire an infectious disease. [1] Because it takes account of susceptibility it can be used to compare the rate of transmission between different groups of the population for the same infectious disease, or even between different infectious diseases.
Plant pathogens can spread rapidly over great distances, vectored by water, wind, insects, and humans. Across large regions and many crop species, it is estimated that diseases typically reduce plant yields by 10% every year in more developed nations or agricultural systems, but yield loss to diseases often exceeds 20% in less developed ...
Companion animals such as cats, dogs, and horses, if not vaccinated, can catch serious viral infections. Canine parvovirus 2 is caused by a small DNA virus, and infections are often fatal in pups. [12] The emergence of the parvovirus in the 1970s was the most significant in the history of infectious diseases.
Hypersensitive response (HR) is a mechanism used by plants to prevent the spread of infection by microbial pathogens.HR is characterized by the rapid death of cells in the local region surrounding an infection and it serves to restrict the growth and spread of pathogens to other parts of the plant.
Unlike human and animal pathology, plant pathology usually focuses on a single causal organism; however, some plant diseases have been shown to be interactions between multiple pathogens. [ 4 ] To colonize a plant, pathogens have specific pathogenicity factors , of five main types: uses of cell wall–degrading enzymes, toxins , effector ...
Plant diseases are diseases in plants caused by pathogens (infectious organisms) and environmental conditions (physiological factors). [1] Organisms that cause infectious disease include fungi , oomycetes , bacteria , viruses , viroids , virus -like organisms, phytoplasmas , protozoa , nematodes and parasitic plants . [ 2 ]
Plant disease epidemiology is the study of disease in plant populations. Much like diseases of humans and other animals, plant diseases occur due to pathogens such as bacteria , viruses , fungi , oomycetes , nematodes , phytoplasmas , protozoa , and parasitic plants . [ 1 ]
Viral infections often develop into systemic infections as a means of transmission. The virus often infects many tissues , if not the whole plant, where it can continue to replicate. There are a variety of methods the virus can use to spread throughout the organism but the most common route use the vascular system, otherwise known as the xylem ...