Infectious Disease from an Epidemiologic Perspective – Eradication of Smallpox, Polio, and COVID-19

Week 9 Discussion – Infectious Disease from an Epidemiologic Perspective – Eradication of

Smallpox, Polio, and COVID-19

The scope of epidemiology has undoubtedly expanded over the past hundred years to
include an investigation of global chronic illnesses, environmental and genetic diseases, and
several other health-related conditions. Despite this expansion, the practice of epidemiology
remains deeply rooted in the appraisal of pandemics, infectious diseases, and global epidemics.
Although today’s epidemiologic efforts are advanced and focus on technology, they still mimic
practices and methods employed several years ago. This discussion explores the epidemiologic
differences between smallpox, polio, and the current COVID-19 and how epidemiology
principles are being applied or could be applied to address the COVID-19 pandemic. Are there
any lessons learned from the use of epidemiology to eradicate smallpox and polio that could be
applied to COVID-19? The discussion further examines the benefits of addressing COVID-19 at
the population versus the individual level.
Epidemiologic Differences Between Smallpox, Polio, and COVID-19 and How Principles of

Epidemiology are Being Applied to Address COVID-19

Firstly, it is important to note that significant epidemiologic differences exist between
smallpox, polio, and COVID-19. Polio or poliomyelitis is a highly infectious illness that affects
youngsters below five years. The poliovirus is spread from person to person mainly via the oral-
fecal route or, less frequently, by contaminated water or food. The disease invades, reproduces,
and multiplies in the intestines. The virus crosses the blood-brain barrier from the intestines and
invades the nervous system, causing paralysis (World Health Organization, n.d.). Therefore,
good sanitation and hygiene practices like handwashing can prevent polio transmission.

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On the other hand, smallpox is a highly contagious disease transmitted through
individual-to-individual contact and saliva droplets in an infected person’s breath. Typically,
smallpox spreads through prolonged contact (face-to-face) via droplets exhaled from an infected
person’s mouth and nose, often by sneezing or coughing. It can also be transmitted by contact
with surfaces contaminated with saliva droplets from an infected person. The variola virus causes
smallpox and can cause millions of deaths if not controlled and eradicated quickly. The last
significant smallpox epidemics were recorded in Boston, Massachusetts, between 1901 and

1903. COVID-19 is spread similarly to smallpox; inhalation or ingestion of saliva droplets
      contaminated with SARS-CoV-2 virus or touching surfaces contaminated with the virus and then
      brushing the eyes, mouth, or nose. Avoiding person-to-person contact through quarantine and
      isolation, coupled with personal hygiene practices like handwashing, are integral in preventing
      the spread of both smallpox and COVID-19.
      Lessons Learned from the Use of Epidemiology in the Eradication of Smallpox and Polio

That Could be Applied to COVID-19

With the unprecedented global spread of COVID-19 witnessed within the past three years
and the unforeseeable future due to emerging variants, epidemiologists and public healthcare
experts can apply previous lessons in eradicating polio and smallpox pandemics to contain the
current COVID-19: fighting the pandemic at the global level. For example, borrowing from
WHO’s 1988 Global Polio Eradication Initiative (GPEI), leading global health bodies like WHO
and the CDC can adopt an intervention for the worldwide eradication of COVID-19. The
initiative must be spearheaded, supported, and possibly funded by national governments in
partnership with WHO, CDC, UNICEF, Red Cross, IMF, and other potential partners (World

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Health Organization, n.d.). Since 1998, wild polio cases have dropped by nearly 99 percent, from
roughly 350,000 cases in at least 125 endemic nations to just 175 in 2019.
A similar global approach was also employed in eradicating smallpox in 1966, in which
more than 10-15 million cases were reported in 50 nations and 1.5-2 million mortalities annually.
International efforts to wipe out polio were intensified in 1965 with the creation of the Smallpox
Eradication Unit at WHO and a pledge for more financial and technical support from the US, the
campaign’s biggest donor. The effort saw endemic countries supplied with tools for collecting
and sending specimens and vaccines. Annually, the cost of running the campaign stood at $23
million between 1967 and 1979. Endemic countries contributed nearly $200 million, while
donors gave $98. The last case of smallpox was reported in 1977 (Center for Global
Development, n.d.). Therefore, one lesson that can be learned from smallpox and polio
eradication efforts that can be applied in fighting COVID-19 is the importance of global efforts.
The Benefits of Addressing COVID-19 and Other Pandemics at the Population Level

Versus the Individual Level

Finally, based on the successes of polio and smallpox campaigns, it can be argued that
addressing global health issues, especially pandemics, at the population level is far much better
than fighting the problem at the individual level. One benefit of the population approach is that it
is comprehensive; it can address underlying causes of a health issue (social determinants of
health) that apply to large groups of people or communities. Social determinants of health
include health system, education, the physical environment and neighborhood, economic
stability, food, and community and social factors.

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References

Center for Global Development. (n.d.). Case 1: Eradicating smallpox.
http://www.cgdev.org/doc/millions/MS_case_1.pdf
Wilson, N., Mansoor, O. D., Boyd, M. J., Kvalsvig, A., & Baker, M. G. (2021). We should not
dismiss the possibility of eradicating COVID-19: Comparisons with smallpox and polio.
BMJ Global Health, 6(8), e006810. https://doi.org/10.1136/bmjgh-2021-006810
World Health Organization. (n.d.). Poliomyelitis (polio). https://www.who.int/health-
topics/poliomyelitis#tab=tab_1