ECONOMICS (CBSE/UGC NET)

Detailed explanation-1: -The origin of smallpox is unknown. The finding of smallpox-like rashes on Egyptian mummies suggests that smallpox has existed for at least 3, 000 years. The earliest written description of a disease like smallpox appeared in China in the 4th century CE (Common Era).

Detailed explanation-2: -Susceptibility and resistance to smallpox (variola) Resolved infection confers lifetime immunity. Pregnant women and people who are immunocompromised are more susceptible to variant forms of smallpox. It is unclear how long the smallpox vaccine provides effective immunity, but it is unlikely to be more than 10 years.

Detailed explanation-3: -Currently, there is no evidence of naturally occurring smallpox transmission anywhere in the world. Although a worldwide immunization program eradicated smallpox disease decades ago, small quantities of smallpox virus officially still exist in two research laboratories in Atlanta, Georgia, and in Russia.

Detailed explanation-4: -The smallpox vaccine is the only way to prevent smallpox. The vaccine is made from a virus called vaccinia, which is another pox-type virus related to smallpox. The vaccine helps the body develop immunity to smallpox. It was successfully used to eradicate smallpox from the human population.