Infectivity

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In epidemiology, infectivity is the ability of a pathogen to establish an infection. More specifically, infectivity is the extent to which the pathogen can enter, survive, and multiply in a host. It is measured by the ratio of the number of people who become infected to the total number exposed to the pathogen. [1]

Infectivity has been shown to positively correlate with virulence, in plants. This means that as a pathogen's ability to infect a greater number of hosts increases, so does the level of harm it brings to the host. [2]

A pathogen's infectivity is different from its transmissibility, which refers to a pathogen's capacity to pass from one organism to another. [1]

See also

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<i>Staphylococcus aureus</i> Species of Gram-positive bacterium

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<span class="mw-page-title-main">Texas root rot</span> Pathogenic fungus

Texas root rot is a disease that is fairly common in Mexico and the southwestern United States resulting in sudden wilt and death of affected plants, usually during the warmer months. It is caused by a soil-borne fungus named Phymatotrichopsis omnivora that attacks the roots of susceptible plants. It was first discovered in 1888 by Pammel and later named by Duggar in 1916.

Virulence is a pathogen's or microorganism's ability to cause damage to a host.

Serial passage is the process of growing bacteria or a virus in iterations. For instance, a virus may be grown in one environment, and then a portion of that virus population can be removed and put into a new environment. This process is repeated with as many stages as desired, and then the final product is studied, often in comparison with the original virus.

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Rickettsia rickettsii is a Gram-negative, intracellular, coccobacillus bacterium that was first discovered in 1902. R. rickettsii is the causative agent of Rocky Mountain Spotted Fever and is transferred to its host via a tick bite. It is one of the most pathogenic Rickettsia species and affects a large majority of the Western Hemisphere, most commonly the Americas.

<span class="mw-page-title-main">Schistosomatidae</span> Family of flukes

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<i>Evolution of Infectious Disease</i>

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<span class="mw-page-title-main">Andrew F. Read</span>

Andrew Fraser Read FRS is Evan Pugh professor of biology and entomology at Pennsylvania State University and the Director of the Huck Institutes of the Life Sciences.

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<span class="mw-page-title-main">Gene-for-gene interactions in rust fungi</span>

The study of gene-for-gene interactions uncovers genetic components, evolutionary impacts, and ecological/economic implications between rust fungi and plants. Rust fungi utilize the gene-for-gene interaction to invade host plants. Conversely, host plants utilize the gene-for-gene interaction to prevent invasion of rust fungi.

<span class="mw-page-title-main">Latent period (epidemiology)</span> Time interval between infection by a pathogen and the individual becoming infectious

In epidemiology, particularly in the discussion of infectious disease dynamics (modeling), the latent period is the time interval between when an individual or host is infected by a pathogen and when that individual becomes infectious, i.e. capable of transmitting pathogens to other susceptible individuals.

References

  1. 1 2 Oxford textbook of global public health (6th ed.). Oxford: Oxford university press. 2015. p. 1486. ISBN   978-0-19-966175-6.
  2. Stewart, AD; Logsdon, JM; Kelley, SE (April 2005). "An empirical study of the evolution of virulence under both horizontal and vertical transmission". Evolution. 59 (4): 730–739. doi:10.1554/03-330. PMID   15926685. S2CID   924610.