The last natural case of smallpox was reported in Dhaka, Bangladesh, involving three-year-old Rahima Banu in October 1975. Smallpox, a highly contagious viral disease characterized by fever and a distinctive skin rash, had plagued humanity for centuries, causing significant mortality and disfigurement. The World Health Organization (WHO) had initiated an aggressive global vaccination campaign against smallpox in 1967. This program aimed not only to control the spread of the disease but also to eradicate it entirely, which was seen as a feasible goal due to the specific nature of the virus and the availability of effective vaccines.

Rahima's case emerged during a period where smallpox vaccination was being intensified. With the active involvement of local health workers, they promptly identified her illness and launched immediate efforts to contain it. The swift response was crucial, preventing further transmission of the virus from the area. Medical teams treated her and conducted mass vaccination campaigns to ensure that her community was protected from similar outbreaks. This diligent response contributed to the efforts initiated by WHO, solidifying the importance of cooperative public health strategies.

Following Rahima Banu's case, no further naturally occurring instances of smallpox were recorded. WHO later declared the disease eradicated in 1980, marking a landmark achievement in public health and global cooperation. Rahima's case became a pivotal point in virology and epidemiology, illustrating the effectiveness of vaccinations and the significance of monitoring and surveillance in public health.