Editing Cowpox (section)

==Medical use==
Naturally occurring cases of cowpox were not common, but it was discovered that the vaccine could be "carried" in humans and reproduced and disseminated human-to-human. Jenner's original vaccination used lymph from the cowpox pustule on a milkmaid, and subsequent "arm-to-arm" vaccinations applied the same principle. As this transfer of human fluids came with its own set of complications, a safer manner of producing the vaccine was first introduced in Italy. The new method used cows to manufacture the vaccine using a process called "retrovaccination", in which a heifer was inoculated with humanized cowpox virus, and it was passed from calf to calf to produce massive quantities efficiently and safely. This then led to the next incarnation, "true animal vaccine", which used the same process but began with naturally-occurring cowpox virus, and not the humanized form.{{Citation needed|date=September 2020}}

This method of production proved to be lucrative and was taken advantage of by many [[entrepreneurs]] needing only calves and seed lymph from an infected cow to manufacture crude versions of the vaccine. W. F. Elgin of the National Vaccine Establishment presented his slightly refined technique to the Conference of State and Provincial Boards of Health of North America. A [[tuberculosis]]-free calf, stomach shaved, would be bound to an operating table, where incisions would be made on its lower body. Glycerinated lymph from a previously inoculated calf was spread along the cuts. After a few days, the cuts would have scabbed or crusted over. The crust was softened with sterilized water and mixed with glycerin, which disinfected it, then stored hermetically sealed in capillary tubes for later use.{{Citation needed|date=September 2020}}

At some point, the virus in use was no longer cowpox, but vaccinia. Scientists have not determined exactly when the change or mutation occurred, but the effects of vaccinia and cowpox virus as vaccine are nearly the same.<ref>{{cite book| vauthors = Willrich M  |title=Pox |url= https://archive.org/details/poxamericanhisto0000will |url-access=registration |date=2011 |publisher= Penguin Books |location=New York}}</ref>

The virus is found in [[Europe]], and mainly in the [[UK]]. Human cases today are very rare and most often [[Feline zoonosis|contracted from]] domestic [[cat]]s. The virus is not commonly found in [[cattle]]; the reservoir hosts for the virus are [[woodland]] [[rodent]]s, particularly [[vole]]s. From these rodents, domestic cats contract and transmit the virus to humans.<ref name="Chomel2014">{{cite journal | vauthors = Chomel BB | title = Emerging and Re-Emerging Zoonoses of Dogs and Cats | journal = Animals | volume = 4 | issue = 3 | pages = 434–445 | date = July 2014 | pmid = 26480316 | pmc = 4494318 | doi = 10.3390/ani4030434 | doi-access = free }}</ref>
Symptoms in cats include [[lesion]]s on the face, neck, forelimbs, and paws, and less commonly upper [[respiratory tract infection]]s.<ref name=Mansell_2005>{{cite book |doi=10.1016/B0-72-160423-4/50005-6 |chapter=Cutaneous Manifestations of Viral Disease |title=Consultations in Feline Internal Medicine |date=2006 |last1=Mansell |first1=Joanne K. |last2=Rees |first2=Christine A. |pages=11–15 |isbn=978-0-7216-0423-7 }}</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.<ref>{{cite book |doi=10.1016/B978-0-7020-3935-5.00057-4 |chapter=Smallpox and Related Orthopoxviral Infections |title=Tropical Infectious Diseases: Principles, Pathogens and Practice |date=2011 |last1=Jahrling |first1=Peter B. |pages=369–377 |isbn=978-0-7020-3935-5 }}</ref>  The [[incubation period]] is 9 to 10 days.{{citation needed|date=October 2021}} The virus is prevalent in late summer and autumn.<ref>{{cite journal |last1=Bruneau |first1=Ryan C. |last2=Tazi |first2=Loubna |last3=Rothenburg |first3=Stefan |title=Cowpox Viruses: A Zoo Full of Viral Diversity and Lurking Threats |journal=Biomolecules |date=8 February 2023 |volume=13 |issue=2 |pages=325 |doi=10.3390/biom13020325 |doi-access=free |pmid=36830694 |pmc=9953750 }}</ref>