Virology in order to immunize others. In 1717 Lady Mary Wortley Montagu observed the practice in Istanbul and attempted to popularize it in Britain, but encountered considerable resistance. In 1796 Edward Jenner developed a much safer method, using cowpox to successfully immunize a young boy against smallpox, and this practice was widely adopted. Vaccinations against other viral diseases followed, including the successful rabies vaccination by Louis Pasteur in 1886. The nature of viruses however was not clear to these researchers. In 1892, the Russian biologist Dmitry Ivanovsky used a Chamberland filter to try to isolate the bacteria that caused tobacco mosaic
1974 smallpox epidemic in India 1974 smallpox epidemic in India The 1974 smallpox epidemic of India was one of the worst smallpox epidemics of 20th century. Over 15,000 people contracted and died from smallpox between January and May 1974. Most of the deaths occurred in the Indian states of Bihar, Orissa and West Bengal. There were thousands who survived but were disfigured or blinded. India reported 61,482 cases of smallpox to World Health Organization (WHO) in these five months. India had over 86% of the world's smallpox cases in 1974, primarily due to this epidemic. By January 1975, an operation was started aimed at containing