Editing Infection (section)

====Host genetic factors====
The organism that is the target of an infecting action of a specific infectious agent is called the host. The host harbouring an agent that is in a mature or sexually active stage phase is called the definitive host. The intermediate host comes in contact during the larvae stage. A host can be anything living and can attain to asexual and sexual reproduction.<ref>{{cite journal|vauthors=Barreto ML, Teixeira MG, Carmo EH|year=2006|title=Infectious diseases epidemiology|journal=Journal of Epidemiology and Community Health|volume=60|issue=3|pages=192–95|doi=10.1136/jech.2003.011593|pmc=2465549|pmid=16476746}}</ref>
The clearance of the pathogens, either treatment-induced or spontaneous, it can be influenced by the genetic variants carried by the individual patients. For instance, for genotype 1 [[hepatitis C]] treated with [[Pegylated interferon-alpha-2a]] or [[Pegylated interferon-alpha-2b]] (brand names Pegasys or PEG-Intron) combined with [[ribavirin]], it has been shown that genetic polymorphisms near the human IL28B gene, encoding interferon lambda 3, are associated with significant differences in the treatment-induced clearance of the virus. This finding, originally reported in ''[[Nature (journal)|Nature]]'',<ref>{{cite journal |vauthors=Ge D, Fellay J, Thompson AJ, Simon JS, Shianna KV, Urban TJ, Heinzen EL, Qiu P, Bertelsen AH, Muir AJ, Sulkowski M, McHutchison JG, Goldstein DB | title = Genetic variation in IL28B predicts hepatitis C treatment-induced viral clearance | journal = Nature | volume = 461 | issue = 7262 | pages = 399–401 | year = 2009 | pmid = 19684573 | doi = 10.1038/nature08309 | bibcode = 2009Natur.461..399G | s2cid = 1707096 }}</ref> showed that genotype 1 hepatitis C patients carrying certain genetic variant alleles near the IL28B gene are more possibly to achieve sustained virological response after the treatment than others. Later report from ''Nature''<ref>{{cite journal |vauthors=Thomas DL, Thio CL, Martin MP, Qi Y, Ge D, O'Huigin C, Kidd J, Kidd K, Khakoo SI, Alexander G, Goedert JJ, Kirk GD, Donfield SM, Rosen HR, Tobler LH, Busch MP, McHutchison JG, Goldstein DB, Carrington M | title = Genetic variation in IL28B and spontaneous clearance of hepatitis C virus | journal = Nature | volume = 461 | issue = 7265 | pages = 798–801 | year = 2009 | pmid = 19759533 | pmc = 3172006 | doi = 10.1038/nature08463 | bibcode = 2009Natur.461..798T }}</ref> demonstrated that the same genetic variants are also associated with the natural clearance of the genotype 1 hepatitis C virus.