Smallpox

"Variola" redirects here. For other uses, see Variola (disambiguation).

Smallpox
Other namesvariola,[1] variola vera,[2] pox,[3] red plague[4]
A child with smallpox in Bangladesh in 1973. The bumps filled with thick fluid and a depression or dimple in the center are characteristic.
SpecialtyInfectious disease
Symptoms
ComplicationsScarring of the skin, blindness[6]
Usual onset1 to 3 weeks following exposure[5]
DurationAbout 4 weeks[5]
Causesvariola major virus, variola minor virus (spread between people)[6][7]
Diagnostic methodBased on symptoms and confirmed by PCR[8]
Differential diagnosisChickenpox, impetigo, molluscum contagiosum, mpox[8]
PreventionSmallpox vaccine[9]
TreatmentSupportive care[10]
MedicationBrincidofovir
Prognosis30% risk of death[5]
FrequencyEradicated (last naturally occuring case in 1977)

Smallpox was an infectious disease caused by variola virus (often called smallpox virus), which belongs to the genus Orthopoxvirus.[7][11] The last naturally occurring case was diagnosed in October 1977, and the World Health Organization (WHO) certified the global eradication of the disease in 1980,[10] making smallpox the only human disease to have been eradicated to date.[12]

The initial symptoms of the disease included fever and vomiting.[5] This was followed by formation of ulcers in the mouth and a skin rash.[5] Over a number of days, the skin rash turned into the characteristic fluid-filled blisters with a dent in the center.[5] The bumps then scabbed over and fell off, leaving scars.[5] The disease was transmitted from one person to another primarily through prolonged face-to-face contact with an infected person or rarely via contaminated objects.[6][13][14] Prevention was achieved mainly through the smallpox vaccine.[9] Once the disease had developed, certain antiviral medications could potentially have helped, but such medications did not become available until after the disease was eradicated.[9] The risk of death was about 30%, with higher rates among babies.[6][15] Often, those who survived had extensive scarring of their skin, and some were left blind.[6]

The earliest evidence of the disease dates to around 1500 BC in Egyptian mummies.[16][17] The disease historically occurred in outbreaks.[10] It was one of several diseases introduced by the Columbian exchange to the New World, resulting in large swathes of Native Americans dying. In 18th-century Europe, it is estimated that 400,000 people died from the disease per year, and that one-third of all cases of blindness were due to smallpox.[10][18] Smallpox is estimated to have killed up to 300 million people in the 20th century[19][20] and around 500 million people in the last 100 years of its existence.[21] Earlier deaths included six European monarchs, including Louis XV of France in 1774.[10][18] As recently as 1967, 15 million cases occurred a year.[10] The final known fatal case occurred in the United Kingdom in 1978.

Inoculation for smallpox appears to have started in China around the 1500s.[22][23] Europe adopted this practice from Asia in the first half of the 18th century.[24] In 1796, Edward Jenner introduced the modern smallpox vaccine.[25][26] In 1967, the WHO intensified efforts to eliminate the disease.[10] Smallpox is one of two infectious diseases to have been eradicated, the other being rinderpest (a disease of even-toed ungulates) in 2011.[27][28] The term "smallpox" was first used in England in the 16th century to distinguish the disease from syphilis, which was then known as the "great pox".[29][30] Other historical names for the disease include pox, speckled monster, and red plague.[3][4][30]

The United States and Russia retain samples of variola virus in laboratories, which has sparked debates over safety.

  1. ^ Barton LL, Friedman NR (2008). The Neurological Manifestations of Pediatric Infectious Diseases and Immunodeficiency Syndromes. Springer Science & Business Media. p. 151. ISBN 978-1-59745-391-2.
  2. ^ Schaller KF (2012). Colour Atlas of Tropical Dermatology and Venerology. Springer Science & Business Media. p. Chapter 1. ISBN 978-3-642-76200-0.
  3. ^ a b Fenner F, Henderson DA, Arita I, Ježek Z, Ladnyi ID (1988). "The History of Smallpox and its Spread Around the World" (PDF). Smallpox and its eradication. History of International Public Health. Vol. 6. Geneva: World Health Organization. pp. 209–44. hdl:10665/39485. ISBN 978-92-4-156110-5. Archived (PDF) from the original on 12 December 2019. Retrieved 14 December 2017.
  4. ^ a b Medicine: The Definitive Illustrated History. Pengui. 2016. p. 100. ISBN 978-1-4654-5893-3.
  5. ^ a b c d e f g h i "Signs and Symptoms". CDC. 7 June 2016. Archived from the original on 7 June 2020. Retrieved 14 December 2017.
  6. ^ a b c d e "What is Smallpox?". CDC. 7 June 2016. Archived from the original on 7 June 2020. Retrieved 14 December 2017.
  7. ^ a b Ryan KJ, Ray CG, eds. (2004). Sherris Medical Microbiology (4th ed.). McGraw Hill. pp. 525–28. ISBN 978-0-8385-8529-0.
  8. ^ a b "Diagnosis & Evaluation". CDC. 25 July 2017. Archived from the original on 9 December 2017. Retrieved 14 December 2017.
  9. ^ a b c "Prevention and Treatment". CDC. 13 December 2017. Archived from the original on 15 December 2017. Retrieved 14 December 2017.
  10. ^ a b c d e f g "Smallpox". WHO Factsheet. Archived from the original on 21 September 2007.
  11. ^ Babkin, I, Babkina, I (March 2015). "The Origin of the variola Virus". Viruses. 7 (3): 1100–12. doi:10.3390/v7031100. ISSN 1999-4915. PMC 4379562. PMID 25763864.
  12. ^ "Smallpox – Symptoms and causes". Mayo Clinic. Archived from the original on 20 April 2022. Retrieved 27 April 2022.
  13. ^ Lebwohl MG, Heymann WR, Berth-Jones J, Coulson I (2013). Treatment of Skin Disease E-Book: Comprehensive Therapeutic Strategies. Elsevier Health Sciences. p. 89. ISBN 978-0-7020-5236-1.
  14. ^ Cite error: The named reference 2012Spread was invoked but never defined (see the help page).
  15. ^ Riedel S (January 2005). "Edward Jenner and the history of smallpox and vaccination". Proceedings. 18 (1): 21–25. doi:10.1080/08998280.2005.11928028. PMC 1200696. PMID 16200144.
  16. ^ "History of Smallpox". CDC. 25 July 2017. Archived from the original on 14 June 2020. Retrieved 14 December 2017.
  17. ^ Thèves C, Crubézy E, Biagini P (2016). "History of Smallpox and Its Spread in Human Populations". Microbiology Spectrum. 4 (4). doi:10.1128/microbiolspec.PoH-0004-2014. ISSN 2165-0497. PMID 27726788. Archived from the original on 8 October 2022. Retrieved 11 September 2022.
  18. ^ a b Hays JN (2005). Epidemics and Pandemics: Their Impacts on Human History. ABC-CLIO. pp. 151–52. ISBN 978-1-85109-658-9.
  19. ^ Koprowski H, Oldstone MB (1996). Microbe hunters, then and now. Medi-Ed Press. p. 23. ISBN 978-0-936741-11-6.
  20. ^ Henderson DA (December 2011). "The eradication of smallpox – an overview of the past, present, and future". Vaccine. 29 (Suppl 4): D7–9. doi:10.1016/j.vaccine.2011.06.080. PMID 22188929.
  21. ^ Henderson D (2009). Smallpox : the death of a disease. Prometheus Books. p. 12. ISBN 978-1-61592-230-7.
  22. ^ Needham J (2000). Science and Civilisation in China: Volume 6, Biology and Biological Technology, Part 6, Medicine. Cambridge University Press. p. 134. ISBN 978-0-521-63262-1. Retrieved 30 March 2020.
  23. ^ Silverstein AM (2009). A History of Immunology (2nd ed.). Academic Press. p. 293. ISBN 978-0080919461..
  24. ^ Strathern P (2005). A Brief History of Medicine. London: Robinson. p. 179. ISBN 978-1-84529-155-6.
  25. ^ Wolfe RM, Sharp LK (August 2002). "Anti-vaccinationists past and present". BMJ. 325 (7361): 430–32. doi:10.1136/bmj.325.7361.430. PMC 1123944. PMID 12193361.
  26. ^ "Smallpox vaccines". WHO. Archived from the original on 30 September 2020. Retrieved 27 March 2020.
  27. ^ Guidotti TL (2015). Health and Sustainability: An Introduction. Oxford University Press. p. T290. ISBN 978-0-19-932568-9.
  28. ^ Roossinck MJ (2016). Virus: An Illustrated Guide to 101 Incredible Microbes. Princeton University Press. p. 126. ISBN 978-1-4008-8325-7.
  29. ^ Harper D. "Smallpox". Online Etymology Dictionary.
  30. ^ a b Barquet N, Domingo P (October 1997). "Smallpox: the triumph over the most terrible of the ministers of death". Annals of Internal Medicine. 127 (8 Pt 1): 635–42. CiteSeerX 10.1.1.695.883. doi:10.7326/0003-4819-127-8_Part_1-199710150-00010. PMID 9341063. S2CID 20357515.