Smallpox and rinderpest have been eradicated. Like love, eradication is not forever. Why not?

 

Eradication - is defined as the process of completely reducing an infectious disease's prevalence to zero in a global scale. This was conducted by the vaccination efforts of countries all over the world.

Both Smallpox and Rinderpest were well-known virus plagues that affected killed many people (Smallpox) and livestock (Rinderpest) for a long period of time. They were declared as eradicated by the World Health Organization (WHO) by 1980 (Smallpox) and 2011 (Rinderpest).

They say that the only thing that is forever constant change, just like love, eradication is not forever. According to an article in 2002, the Central Intelligence Agency (CIA) had significant evidence that nations, such as Iraq, Russia, North Korea, and France, have hidden stores of smallpox virus. This means that these countries have live viruses in secret, that could possibly cause an outbreak or be used as lethal Biological Weapons, which in turn, invalidate the eradication efforts of CDC and WHO.

Another possible point of view that could cause the revival of these viruses is the theory of evolution. Just like what happened in SARS-COV2 or COVID-19, it is possible that virus strains related to smallpox or rinderpest that were previously harmless or noninfectious, undergo a series of mutation that leads to a formation of an a new strain of that virus.

Step-by-step explanation

The eradication of Smallpox and Rinderpest was made possible due to the vaccines that effectively cut the transmission and cycle of infection to susceptible hosts.

Vaccines, from the Latin word, "vacca", that literally means as "cow". This was named after the fact that it was coined by Edward Jenner from his observation that Milkmaids (cow milk collectors) were not affected by Smallpox after being infected by Cowpox. Cowpox is a milder strain of virus related to smallpox, that infected people and only produced mild disease with little or no symptoms. Jenner, noticed that when the milkmaids who had a history cowpox, were exposed to smallpox, they did not develop the disease.

This is the principle of Cross-immunity, in which an individual's immunity against a certain strain (Cowpox) also protects that individual to other strains (Smallpox) that are similar or related to the first strain. Thus, this led Jenner to test his theory by administering cowpox to a boy and then exposing that same boy to smallpox. This discovery of cross-immunity paved the way of vaccination, in which helped the world get rid the dreaded diseases such as, Smallpox and Rinderpest.