Which of the following diseases has been completely eradicated through vaccination efforts?

The disease that has been completely eradicated through vaccination efforts is smallpox. This achievement is significant, as smallpox is the first and only human disease to be eradicated. The global vaccination campaign led by the World Health Organization (WHO), which began in the 1960s, employed a strategy of widespread vaccination, surveillance, and containment. Ultimately, in 1980, the WHO declared smallpox eradicated, marking a monumental milestone in public health.

In contrast to smallpox, other diseases mentioned, such as polio, tetanus, and rubella, have not been completely eradicated despite successful vaccination programs. For instance, while polio has been significantly reduced globally and is close to eradication, it has not yet been completely eliminated in every country. Tetanus is preventable through vaccination but continues to exist, mainly due to the presence of the bacteria in the environment; it is a non-communicable disease meaning it doesn’t spread between people. Similarly, rubella has seen a decrease in incidence thanks to vaccination, but cases still occur, particularly in areas with low vaccination coverage. Thus, smallpox remains unique in its complete eradication.