Difference between revisions of "Cowpox" - New World Encyclopedia

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{{DiseaseDisorder infobox |
 
{{DiseaseDisorder infobox |
  Name       = Cowpox |
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Name   = Cowpox |
   ICD10       = B08.0 |
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Image          = Cowpox Engraving (detail).png|
  ICD9       = {{ICD9|051.0}} |
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   Caption        = Engraving of a cow's udder with vaccinia pustules|
   MeshID     = D015605 |
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ICD10   = B08.0 |
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ICD9   = {{ICD9|051.0}} |
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   ICDO          = |
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MeshID   = D015605 |
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DiseasesDB = 31392 |
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OMIM          = |
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  MedlinePlus    = |
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  eMedicineSubj  = med |
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  eMedicineTopic = |
 
}}
 
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'''Cowpox''' is a rare, mildly contagious skin [[disease]] caused by the cowpox virus, which has gained fame because of its use in the eighteenth century for [[immunization]] against [[smallpox]], a deadly disease from the same family of [[virus]]es as cowpox. Cowpox received its name from milkmaids touching the [[udder]]s of infected [[cow]]s; however, today it is acquired most often from contact with an infected [[cat]] and is also known as '''catpox''' and the virus as catpox virus.
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The virus is found in [[Europe]], but is very rare today. Infection in humans results in localized, pustular (producing pus) lesions at the site the virus enters the skin; death is very rare (Aguayo and Calderón; Levin 2007).
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{{Taxobox | color=violet
 
{{Taxobox | color=violet
 
| name = ''Cowpox virus''
 
| name = ''Cowpox virus''
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| species = '''''Cowpox virus'''''
 
| species = '''''Cowpox virus'''''
 
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'''Cowpox''' (also known as '''Catpox''') is a [[disease]] of the skin that is caused by a [[virus]] known as the '''''Cowpox virus'''''. The [[pox]] is related to the ''[[vaccinia]]'' virus, and got its name from [[cow maid]]s touching the [[udder]]s of infected cows. The ailment manifests itself in the form of red [[blister]]s and is transmitted by touch from infected animals to [[human]]s. When it is gone, the person is immune to smallpox.
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The discovery of this nature-provided means of [[inoculation|inoculating]] against smallpox led the way in elimination of a disease that killed an estimated 400,000 Europeans each year during the eighteenth century, and even an estimated 300 to 500 million deaths in the twentieth century before smallpox was completely eradicated.
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==Cowpox virus==
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The cowpox virus is a type of ''Orthopoxvirus'', a group that includes ''[[buffalopox virus]]'', ''[[camelpox virus]]'', ''[[monkeypox virus]]'', ''[[rabbitpox virus]]'', ''[[sealpox virus]]'', ''[[volepox virus]]'' and ''[[Ectromelia virus]]'', which causes mousepox. The most famous member of the genus is ''[[Variola virus]]'', which causes [[smallpox]]. Members of the Orthopoxvirus taxonomic group are members of Poxviridae (poxviruses) and the subfamily [[Chordopoxvirinae]], members of which exclusively infect [[chordate]]s.
  
The cowpox virus was used to perform the first successful [[vaccination]] against another disease, [[smallpox]], which is caused by the related ''[[Variola virus]]''. Therefore, the word "vaccination" — first used by [[Edward Jenner]] (an English physician) in 1796{{Fact|date=December 2007}} — has the [[Latin]] root ''vacca'' meaning cow, or from [[Latin]] root ''vaccinia'' meaning cowpox.
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As a member of the ''Orthopoxvirus'' taxon, cowpow is a double-stranded [[DNA virus]] that replicates in the [[cytoplasm]] of the [[cell (biology)|cell]] (Levin 2007). The virus binds to receptors on the [[plasma membrane]] of host cells and enters the cytoplasm, where the DNA is replicated and new viral particles assembled (Levin 2007). These are released when the cell lyses and can then enter nearby cells (Levin 2007). The DNA does not integrate into the host cell and there is no latent stage (Levin 2007).
  
== Origin ==
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The main reservoir hosts of the cowpox virus are [[rodent]]s, but it can spread to [[cattle]], [[cat]]s, [[human]]s, and zoo animals, such as [[elephant]]s and large felids (Aguayo and Calderón). The main reservoir hosts are woodland rodents, particularly [[vole]]s and wood mice. It is from these rodents that domestic cats contract the virus. Humans, cattle, and cats are only accidental hosts (Levin 2007). Symptoms in cats include [[lesion]]s on the face, neck, forelimbs, and paws, and less commonly upper respiratory tract infection (Mansell and Rees 2006).
{{Totally-disputed|date=March 2008}}
 
In the years 1770 till 1791 at least 6 people had tested independently the possibility of using the cowpox vaccine as an immunisation for smallpox in humans for the first time; among them the English farmer [[Benjamin Jesty]], in [[Dorset]], [[England]] in 1774 and the German teacher Peter Plett in 1791.<ref>{{cite journal |author=Plett PC |title=[Peter Plett and other discoverers of cowpox vaccination before Edward Jenner] |language=German |journal=Sudhoffs Arch |volume=90 |issue=2 |pages=219–32 |year=2006 |pmid=17338405 |doi= |url=}}</ref> Jesty inoculated his wife and two young sons and thus spared them probable death by smallpox which was raging in the area in which they lived. His patients who had contracted and recovered from cowpox (mainly milkmaids), a disease similar to but much milder than smallpox, seemed to be [[immune]] not only to further cases of cowpox, but also to smallpox. By scratching the fluid from cowpox lesions into the skin of healthy individuals, he was able to immunize those people against smallpox. It was reported that farmers and people working regularly with cows and horses were often spared during smallpox outbreaks. More and more an investigation conducted towards 1790 by the Royal Army showed that horse-mounted troops were less infected by smallpox than [[infantry]], and this due to a major exposure to the ''horse pox'' virus, with similar traits with cowpox's one.
 
However, credit was stolen by the politically astute Dr. Jenner who performed his first inoculation, twenty-two years later. It is said that Jenner made this discovery by himself without any ideas or help from others. Although Jesty was first to discover it, Jenner let everyone know and understand it, thus taking full credit for it.
 
  
The virus is found in [[Europe]], and mainly in the [[UK]]. Human cases today are very rare and most often contracted from domestic [[cat]]s. The virus is not commonly found in [[cow]]s; the reservoir hosts for the virus are woodland rodents, particularly [[vole]]s. It is from these rodents that domestic cats contract the virus. Symptoms in cats include [[lesion]]s on the face, neck, forelimbs, and paws, and less commonly upper respiratory tract infection.<ref name=Mansell_2005>{{cite book|editor=August, John R. (ed.)|chapter=Cutaneous manifestations of viral disease|author=Mansell, Joanne K.;Rees, Christine A.|title=Consultations in Feline Internal Medicine Vol. 5|publisher=Elsevier Saunders|year=2005|id=ISBN 0-7216-0423-4}}</ref>  Symptoms of infection with cowpox virus in humans are localized, pustular lesions generally found on the hands and limited to the site of introduction.  The incubation period is nine to ten days. The virus is prevalent in late [[summer]] and [[autumn]].
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==Cowpox in humans==
 +
The cowpox virus is believed to be transmitted to humans by direct contact with an infected animal, with the virus entering through broken skin (Levin 2007). Although historically cowpox infection has been associated with transmission from cattle, from the infected teats of cows being milked, today it is most commonly acquired from domestic [[cat]]s (Aguayo and Calderón).
  
== Kinepox ==
+
Generally infection remains localized at the site of infection, with infection producing pustular lesions where the virus enters the skin (Levin 2007; Aguayo and Calderón). Common sites for the lesions are the hands, the thumbs, the first interdigital cleft, and the forefinger (Aguayo and Calderón). Levin (2007) reports that there are usually only one or a small number of lesions on the hands (48 percent) and face (33 percent). The vesicopustular lesions on the hands or face subsequently ulcerate and develop a black eschar before regressing spontaneously (Levin 2007; Aguayo and Calderón). However, lymphatic spread and more generalized skin infection have been reported (Levin 2007; Aguayo and Calderón). Wider spread and death are rare (Levin 2007). The incubation period is nine to ten days.
Kinepox is an alternate term for the [[smallpox vaccine]] used in early 19th century America. Popularized by Jenner in the late 1790s, kinepox was a far safer method for inoculating people against smallpox than the previous method, [[variolation]], which had a 3% fatality rate.
 
  
In a famous letter to [[Meriwether Lewis]] in 1803, [[Thomas Jefferson]] instructed the [[Lewis and Clark expedition]] to "carry with you some matter of the kine-pox; inform those of them with whom you may be, of its efficacy as a preservative from the smallpox; & encourage them in the use of it..."<ref>{{cite web | url = http://www.library.csi.cuny.edu/dept/history/lavender/jefflett.html | title = Jefferson's Instructions to Lewis and Clark (1803) | accessdate = 2007-08-10 | format = | work = }}</ref> Jefferson had developed an interest in protecting Native Americans from smallpox having been aware of [[epidemic]]s along the [[Missouri River]] during the previous century. One year prior to his special instructions to Lewis, Jefferson had persuaded a visiting [[delegation]] of North American Indian Chieftains to be vaccinated with kinepox during the winter of 1801-2. Unfortunately, Lewis never got the opportunity to use kinepox during the pair's expedition as it had become inadvertently inactive &mdash; a common occurrence in a time before vaccines were stabilized with preservatives like [[glycerol]] or kept at refrigeration temperatures.
+
Cowpox in humans tends to be self-limiting, with the [[immune system]] able to control the infection and the only remnant being scars at the site of the lesions (Levin 2007).  
  
==Historical use==
+
Human cases today are very rare. Fewer than 150 human cases have been reported, with most incidences having been reported in [[Great Britain]], and smaller numbers of cases from [[Germany]], [[Belgium]], [[France]], [[Netherlands]], [[Sweden]], [[Finland]], [[Norway]], and [[Russia]] (Levin 2007). The [[United States]] has had no reported cases of cowpox (Levin 2007). According to Vestey et al. (1991), cowpox virus infections between 1985 and 1990 were reported at the rate of approximately two per year, but they note that the actual incidences of the disease was probably considerably higher.
[[Image:The cow pock.jpg|thumb|300px|Caricature by [[James Gillray]] concerning vaccination with cowpox, depicting recipients of the vaccine developing cow-like appendages]]
+
 
Cowpox was the original vaccine of sorts for [[smallpox]]. After infection with the disease, the body (usually) gains the ability of recognizing the similar smallpox virus from its antigens and so is able to fight the smallpox disease much more efficiently. The vaccinia virus now used for smallpox vaccination is sufficiently different from the cowpox virus found in the wild as to be considered a separate virus. <ref>Yuan, Jenifer [http://www.stanford.edu/group/virus/pox/history.html The Small Pox Story]</ref>
+
==Cowpox role in immunization against smallpox==
 +
[[Image:The cow pock.jpg|thumb|300px|Caricature by [[James Gillray]] concerning vaccination with cowpox, depicting recipients of the vaccine developing cow-like appendages.]]
 +
The deadly [[smallpox]] disease is caused by the virus ''[[Variola virus]]'', which is related to the cowpox virus. After infection with the disease cowpox, the body (usually) gains the ability of recognizing the similar smallpox virus from its [[antigen]]s and so is able to fight the smallpox disease much more efficiently. The cowpox virus was used to perform the first successful [[vaccination]] against another disease when it was employed against smallpox.
 +
 
 +
The credit for immunization against smallpox generally goes to [[Edward Jenner]] (1749-1823), who in 1796 inoculated against smallpox using cowpox. While Edward Jenner has been recognized as the first doctor to give sophisticated [[immunization]], at least six other people before Jenner had independently tested the possibility of using the cowpox vaccine as an immunization for smallpox in humans, including Benjamin Jestey in 1774 and the German teacher Peter Plett in 1791 (Plett 2006). Two decades before Jenner's inoculation, British dairy farmer Benjamin Jestey noticed that "milkmaids" did not become infected with [[smallpox]], or displayed a milder form. Jestey took the pus from an infected [[cow]]'s udder and inoculated his wife and children with cowpox, in order to artificially induce immunity to smallpox during the [[epidemic]] of 1774, thereby making them immune to smallpox. It had been reported that farmers and people working regularly with cows and horses were often spared during smallpox outbreaks. Between 1790 and 1792, Plett (1766-1823), who recognized the wider importance of his discovery, reported his findings to the Medical Faculty of the University of Kiel, but the faculty disregarded Plett's reports and neither responded to them nor changed their preferred method, variolation (Plett 2006).
 +
 
 +
Twenty-two years after Jestey, Jenner found that by injecting a human with the cowpox virus, the immunized human was then also immune to smallpox. Vaccination to prevent smallpox was soon practiced all over the world. During the nineteenth century, the cowpox virus used for smallpox vaccination was replaced by ''Vaccinia'' virus. ''Vaccinia'' is in the same family as cowpox and ''Variola'', but is genetically distinct from both. After successful vaccination campaigns throughout the nineteenth and twentieth centuries, the World Health Organization (WHO) certified the eradication of smallpox in 1979. The word vaccination is variously attributed to the [[Latin]] root ''vacca'', meaning "cow," or from Latin root ''vaccinia''.
 +
 
 +
The vaccinia virus now used for smallpox vaccination is sufficiently different from the cowpox virus found in the wild as to be considered a separate virus (Yuan 1999).
 +
 
 +
=== Kinepox and early nineteenth century America===
 +
Kinepox (cowpox fluid) is an alternate term used for the smallpox vaccine in early nineteenth-century America. Popularized by Jenner in the late 1790s, kinepox was a far safer method for inoculating people against smallpox than the previous method, [[variolation]], which had a three percent fatality rate. (Variolation involved purposefully infecting a person with smallpox (Variola) in a controlled manner so as to minimize the severity of the infection and also to induce immunity against further infection.)
 +
 
 +
In a famous letter to [[Meriwether Lewis]] in 1803, [[Thomas Jefferson]] instructed the [[Lewis and Clark expedition]] to "carry with you some matter of the kine-pox; inform those of them with whom you may be, of its efficacy as a preservative from the smallpox; and encourage them in the use of it..." (Jefferson 1803). Jefferson had developed an interest in protecting Native Americans from smallpox having been aware of [[epidemic]]s along the [[Missouri River]] during the previous century. One year prior to his special instructions to Lewis, Jefferson had persuaded a visiting [[delegation]] of North American Indian Chieftains to be vaccinated with kinepox during the winter of 1801-1802. Unfortunately, Lewis never got the opportunity to use kinepox during the pair's expedition as it had become inadvertently inactive&mdash;a common occurrence in a time before vaccines were stabilized with preservatives like [[glycerol]] or kept at refrigeration temperatures.
  
 
==References==
 
==References==
<references/>
 
 
Jennifer Aguayo and Jessica Calderón.
 
http://www.stanford.edu/group/virus/pox/2000/cowpox_virus.html Cowpox virus 
 
Poxviridae
 
  
Nikki A Levin
+
* Aguayo, J, and J. Calderón. n.d. [http://www.stanford.edu/group/virus/pox/2000/cowpox_virus.html Cowpox virus] ''Standford University''. Retrieved July 31, 2008.
[http://www.emedicine.com/derm/topic87.htm Cowpox Infection, Human]. ''eMedicine''.  
+
* Jefferson, T. 1803. [https://csivc.csi.cuny.edu/history/files/lavender/jefflettques.html President Thomas Jefferson's instructions to Captain Meriwether Lewis (June 20, 1803)] ''College of Staten Island of The City University of New York''. Retrieved July 22, 2016.
Article Last Updated: Feb 21, 2007
+
* Levin, N. A. 2007. Cowpox infection, human ''eMedicine''.
 +
* Mansell, J. K, and C. A. Rees. 2006. Cutaneous manifestations of viral disease. In J. R. August (ed.), ''Consultations in Feline Internal Medicine'', vol. 5. St. Louis, Mo: Elsevier Saunders. ISBN 0721604234.
 +
* Peck, D. R. 2002. ''Or Perish in the Attempt: Wilderness Medicine in the Lewis & Clark Expedition''. Helena, MT: Farcountry Press. ISBN 1560372265. Retrieved July 31, 2008.
 +
* Plett, P. C. 2006. [http://www.ncbi.nlm.nih.gov/pubmed/17338405 Peter Plett and other discoverers of cowpox vaccination before Edward Jenner] ''Sudhoffs Arch'' 90(2): 219–32. PMID 17338405.
 +
* Vestey, J. P., D. L. Yirrell, and R. D. Aldridge. 1991. Cowpox/catpox infection. ''British Journal of Dermatology'' 124(1): 74-78.
 +
* Yuan, J. 1999. [http://www.stanford.edu/group/virus/pox/history.html The small pox story] ''Standford University''. Retrieved July 31,2008.
  
== Sources ==
 
* {{cite book | author = Peck, David R. | title = Or Perish in the Attempt: Wilderness Medicine in the Lewis & Clark Expedition | publisher = Farcountry Press | location = | year = | pages = | isbn = 1-56037-226-5 | oclc = | doi = }}
 
  
 
{{Viral diseases}}
 
{{Viral diseases}}

Latest revision as of 00:16, 15 January 2023

Cowpox
Cowpox Engraving (detail).png

Engraving of a cow's udder with vaccinia pustules
ICD-10 B08.0
ICD-O:
ICD-9 051.0
OMIM [1]
MedlinePlus [2]
eMedicine med/
DiseasesDB 31392

Cowpox is a rare, mildly contagious skin disease caused by the cowpox virus, which has gained fame because of its use in the eighteenth century for immunization against smallpox, a deadly disease from the same family of viruses as cowpox. Cowpox received its name from milkmaids touching the udders of infected cows; however, today it is acquired most often from contact with an infected cat and is also known as catpox and the virus as catpox virus.

The virus is found in Europe, but is very rare today. Infection in humans results in localized, pustular (producing pus) lesions at the site the virus enters the skin; death is very rare (Aguayo and Calderón; Levin 2007).

Cowpox virus
Virus classification
Group: Group I (dsDNA)
Family: Poxviridae
Genus: Orthopoxvirus
Species: Cowpox virus

The discovery of this nature-provided means of inoculating against smallpox led the way in elimination of a disease that killed an estimated 400,000 Europeans each year during the eighteenth century, and even an estimated 300 to 500 million deaths in the twentieth century before smallpox was completely eradicated.

Cowpox virus

The cowpox virus is a type of Orthopoxvirus, a group that includes buffalopox virus, camelpox virus, monkeypox virus, rabbitpox virus, sealpox virus, volepox virus and Ectromelia virus, which causes mousepox. The most famous member of the genus is Variola virus, which causes smallpox. Members of the Orthopoxvirus taxonomic group are members of Poxviridae (poxviruses) and the subfamily Chordopoxvirinae, members of which exclusively infect chordates.

As a member of the Orthopoxvirus taxon, cowpow is a double-stranded DNA virus that replicates in the cytoplasm of the cell (Levin 2007). The virus binds to receptors on the plasma membrane of host cells and enters the cytoplasm, where the DNA is replicated and new viral particles assembled (Levin 2007). These are released when the cell lyses and can then enter nearby cells (Levin 2007). The DNA does not integrate into the host cell and there is no latent stage (Levin 2007).

The main reservoir hosts of the cowpox virus are rodents, but it can spread to cattle, cats, humans, and zoo animals, such as elephants and large felids (Aguayo and Calderón). The main reservoir hosts are woodland rodents, particularly voles and wood mice. It is from these rodents that domestic cats contract the virus. Humans, cattle, and cats are only accidental hosts (Levin 2007). Symptoms in cats include lesions on the face, neck, forelimbs, and paws, and less commonly upper respiratory tract infection (Mansell and Rees 2006).

Cowpox in humans

The cowpox virus is believed to be transmitted to humans by direct contact with an infected animal, with the virus entering through broken skin (Levin 2007). Although historically cowpox infection has been associated with transmission from cattle, from the infected teats of cows being milked, today it is most commonly acquired from domestic cats (Aguayo and Calderón).

Generally infection remains localized at the site of infection, with infection producing pustular lesions where the virus enters the skin (Levin 2007; Aguayo and Calderón). Common sites for the lesions are the hands, the thumbs, the first interdigital cleft, and the forefinger (Aguayo and Calderón). Levin (2007) reports that there are usually only one or a small number of lesions on the hands (48 percent) and face (33 percent). The vesicopustular lesions on the hands or face subsequently ulcerate and develop a black eschar before regressing spontaneously (Levin 2007; Aguayo and Calderón). However, lymphatic spread and more generalized skin infection have been reported (Levin 2007; Aguayo and Calderón). Wider spread and death are rare (Levin 2007). The incubation period is nine to ten days.

Cowpox in humans tends to be self-limiting, with the immune system able to control the infection and the only remnant being scars at the site of the lesions (Levin 2007).

Human cases today are very rare. Fewer than 150 human cases have been reported, with most incidences having been reported in Great Britain, and smaller numbers of cases from Germany, Belgium, France, Netherlands, Sweden, Finland, Norway, and Russia (Levin 2007). The United States has had no reported cases of cowpox (Levin 2007). According to Vestey et al. (1991), cowpox virus infections between 1985 and 1990 were reported at the rate of approximately two per year, but they note that the actual incidences of the disease was probably considerably higher.

Cowpox role in immunization against smallpox

Caricature by James Gillray concerning vaccination with cowpox, depicting recipients of the vaccine developing cow-like appendages.

The deadly smallpox disease is caused by the virus Variola virus, which is related to the cowpox virus. After infection with the disease cowpox, the body (usually) gains the ability of recognizing the similar smallpox virus from its antigens and so is able to fight the smallpox disease much more efficiently. The cowpox virus was used to perform the first successful vaccination against another disease when it was employed against smallpox.

The credit for immunization against smallpox generally goes to Edward Jenner (1749-1823), who in 1796 inoculated against smallpox using cowpox. While Edward Jenner has been recognized as the first doctor to give sophisticated immunization, at least six other people before Jenner had independently tested the possibility of using the cowpox vaccine as an immunization for smallpox in humans, including Benjamin Jestey in 1774 and the German teacher Peter Plett in 1791 (Plett 2006). Two decades before Jenner's inoculation, British dairy farmer Benjamin Jestey noticed that "milkmaids" did not become infected with smallpox, or displayed a milder form. Jestey took the pus from an infected cow's udder and inoculated his wife and children with cowpox, in order to artificially induce immunity to smallpox during the epidemic of 1774, thereby making them immune to smallpox. It had been reported that farmers and people working regularly with cows and horses were often spared during smallpox outbreaks. Between 1790 and 1792, Plett (1766-1823), who recognized the wider importance of his discovery, reported his findings to the Medical Faculty of the University of Kiel, but the faculty disregarded Plett's reports and neither responded to them nor changed their preferred method, variolation (Plett 2006).

Twenty-two years after Jestey, Jenner found that by injecting a human with the cowpox virus, the immunized human was then also immune to smallpox. Vaccination to prevent smallpox was soon practiced all over the world. During the nineteenth century, the cowpox virus used for smallpox vaccination was replaced by Vaccinia virus. Vaccinia is in the same family as cowpox and Variola, but is genetically distinct from both. After successful vaccination campaigns throughout the nineteenth and twentieth centuries, the World Health Organization (WHO) certified the eradication of smallpox in 1979. The word vaccination is variously attributed to the Latin root vacca, meaning "cow," or from Latin root vaccinia.

The vaccinia virus now used for smallpox vaccination is sufficiently different from the cowpox virus found in the wild as to be considered a separate virus (Yuan 1999).

Kinepox and early nineteenth century America

Kinepox (cowpox fluid) is an alternate term used for the smallpox vaccine in early nineteenth-century America. Popularized by Jenner in the late 1790s, kinepox was a far safer method for inoculating people against smallpox than the previous method, variolation, which had a three percent fatality rate. (Variolation involved purposefully infecting a person with smallpox (Variola) in a controlled manner so as to minimize the severity of the infection and also to induce immunity against further infection.)

In a famous letter to Meriwether Lewis in 1803, Thomas Jefferson instructed the Lewis and Clark expedition to "carry with you some matter of the kine-pox; inform those of them with whom you may be, of its efficacy as a preservative from the smallpox; and encourage them in the use of it..." (Jefferson 1803). Jefferson had developed an interest in protecting Native Americans from smallpox having been aware of epidemics along the Missouri River during the previous century. One year prior to his special instructions to Lewis, Jefferson had persuaded a visiting delegation of North American Indian Chieftains to be vaccinated with kinepox during the winter of 1801-1802. Unfortunately, Lewis never got the opportunity to use kinepox during the pair's expedition as it had become inadvertently inactive—a common occurrence in a time before vaccines were stabilized with preservatives like glycerol or kept at refrigeration temperatures.

References
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