Why do we no longer vaccinate for smallpox?

The United States, along with most of the world, stopped routine smallpox vaccination in the 1970s after the disease had been eradicated after a successful immunization program. Here are some reasons why we no longer vaccinate for smallpox:

1. Eradication of Smallpox: Smallpox became the first and only disease to be completely eradicated through vaccination. The World Health Organization (WHO) certified the global eradication of smallpox in 1980, thanks to widespread immunization campaigns and rigorous surveillance. With no known cases of smallpox existing in the wild, the risk of contracting the disease is considered exceptionally low.

2. Limited Risk of Resurgence: Since the eradication of smallpox, natural transmission of the virus has ceased. The variola virus, which causes smallpox, is not known to exist outside of a few high-security laboratory facilities. This greatly reduces the chances of the disease re-emerging naturally.

3. Potential Risks of Vaccination: While the smallpox vaccine was highly effective in preventing the disease, it was not without risks. Some individuals experienced adverse reactions, including fever, skin rash, and in rare cases, serious complications like encephalitis. The risk of these adverse events, though small, contributed to the decision to discontinue routine vaccination when the disease was no longer a significant public health threat.

4. Resource Allocation: With smallpox eradicated, healthcare resources can be redirected to addressing other pressing health challenges. By discontinuing routine smallpox vaccination, countries can focus their efforts and funding on combating prevalent diseases and improving overall public health.

5. International Collaboration: The successful global eradication of smallpox highlighted the power of international cooperation in disease prevention. By working together, nations can address public health threats collectively and effectively, making routine vaccination for eradicated diseases unnecessary.

6. Surveillance and Preparedness: Despite the eradication of smallpox, surveillance mechanisms remain in place to monitor for any signs of the disease's reemergence. Countries maintain a state of preparedness, including stockpiles of smallpox vaccine and plans for rapid response in case of any potential outbreaks.

It's essential to note that while routine smallpox vaccination is no longer necessary, the availability of vaccines and the expertise to produce them ensures that rapid action can be taken if the disease were to ever re-emerge.