From Wikipedia: Tetralogy of Fallot (TOF) is a congenital heart defect which is classically understood to involve four anatomical abnormalities (although only three of them are always present). It is the most common cyanotic heart defect, representing 55-70%, and the most common cause of blue baby syndrome..
Variola (the virus that causes smallpox) is a member of the orthopoxvirus genus, which also includes viruses that cause cowpox, monkeypox, orf, and molluscum contagiosum. Poxviruses are the largest animal viruses, visible with a light microscope.They are larger than some bacteria and contain double-stranded DNA. Poxviruses are the only viruses that do not need a cell's nucleus to replicate inside the cell. The variola virus is the only known cause of smallpox.The disease affects only humans.oxviruses are the only viruses that do not need a cell's nucleus to replicate inside the cell. The variola virus is the only known cause of smallpox. The disease affects only humans.
The smallpox vaccine helps the body develop immunity to smallpox. The vaccine is made from a virus called vaccinia which is a pox-type virus related to smallpox. The smallpox vaccine contains the live vaccinia virus-not dead virus like many other vaccines.For that reason, the vaccination site must be cared for carefully to prevent the virus from spreading.he vaccine is made from a virus called vaccinia which is a pox-type virus related to smallpox. The smallpox vaccine contains the live vaccinia virus-not dead virus like many other vaccines.