Until the eradication of smallpox in 1980, it was one of the most feared diseases of mankind. Although smallpox is very similar to pox viruses of other animals, it is targeted to humans and there is no animal known which can “store” the virus and infect people. This fact made it possible to rid the world of smallpox entirely. The last natural case was in 1977, and the last lab-acquired case was in 1978 (Smith & McFadden, 2002).
The first preventive method against smallpox was variolation, which was developed in Asia (variola is the scientific name for smallpox). In variolation, the individual was infected when dried smallpox scabs were blown into the nose. The disease was much milder this way, it provided lifetime immunity, and fewer people died (1-2% vs. 30% or more with natural smallpox) (National Library of Medicine, 2013). Later, Europeans and Americans developed inoculation, in which a person became infected when the disease was injected into the skin. Both methods had potential dangers; the patient could die but also, since the variola virus itself was used, a person with a mild case could spread it and provoke an epidemic. A new method was needed.
Most people have heard of Jenner, who discovered that milkmaids were less likely to develop smallpox. The immunity appeared to be related to infection with cowpox. He experimented with giving cowpox — variolae vaccinae — to children, then exposing them to smallpox. He was excited to find that the children did not contract smallpox. Cowpox could still make a person sick, but it was much milder than natural smallpox or even that acquired by variolation (Riedel, 2005).
Today, vaccination against smallpox is rare, since the disease has been eradicated. Certain military personnel and scientists still receive vaccinations. The first vaccination lasts 3-5 years (CDC, 2004), but later doses will last longer.
I believe that vaccines, including smallpox vaccine, are crucial to maintaining public health. Although getting a vaccination is a personal issue, it is also a community issue, because a person can spread diseases like smallpox for several days without appearing ill. In fact, some diseases, including measles and whooping cough, have already made a comeback due to substantial unvaccinated populations.
- Centers for Disease Control (CDC). Emergency preparedness and response: Smallpox. Retrieved from http://www.bt.cdc.gov/agent/smallpox/
- National Library of Medicine (NLM). (2013). Smallpox: A great and terrible scourge. Retrieved from http://www.nlm.nih.gov/exhibition/smallpox/sp_variolation.html.
- Riedel, S. (2005). Edward Jenner and the history of smallpox and vaccination. Proceedings (Baylor University Medical Center) 18: 21-25.
- Smith, G., McFadden, G. (2002). Smallpox: Anything to Declare? Nature Reviews Immunology. Retrieved from http://www.nature.com/nri/journal/v2/n7/full/nri845.html. http://dx.doi.org/10.1038/nri845