about a hundred years ago, when small pox persisted, a group of people who had this disease earlier, survived as they had no chance of suffering from it again. So, having the disease once was mean of preventing the subsequest attack of the same disease 1) why does this happen? explain 2) can we 'fool' the immune system? explain. 3) name this principle of prevention of disease.
Answers
Answer:
Smallpox was an infectious disease caused by one of two virus variants, Variola major and Variola minor.[7] The last naturally occurring case was diagnosed in October 1977, and the World Health Organization (WHO) certified the global eradication of the disease in 1980.[10] The risk of death after contracting the disease was about 30%, with higher rates among babies.[6][11] Often those who survived had extensive scarring of their skin, and some were left blind.
Answer:
Smallpox was an infectious disease caused by one of two virus variants, Variola major and Variola minor.[7] The last naturally occurring case was diagnosed in October 1977, and the World Health Organization (WHO) certified the global eradication of the disease in 1980.[10] The risk of death after contracting the disease was about 30%, with higher rates among babies.[6][11] Often those who survived had extensive scarring of their skin, and some were left blind.[6]
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