Mumps
Mumps is spread from person to person through contact with respiratory secretions, such as saliva from an infected person. When an infected person coughs or sneezes, the droplets aerosolize and can enter the eyes, nose, or mouth of another person. Mumps can also be spread by sharing eating utensils or cups. The virus can also survive on surfaces and then be spread after contact in a similar manner. A person infected with mumps is contagious from approximately seven days before the onset of symptoms until about eight days after symptoms start. The incubation period (time until symptoms begin) can be from 12–25 days, but is typically 16–18 days. 20-40 percent of persons infected with the mumps virus do not show symptoms, so it is possible to be infected and spread the virus without knowing it.
ACAM2000
Smallpox works in the following way:"Smallpox spreads from one person to another by infected saliva droplets. The incubation period is 7 to 17 days. The symptoms begin with severe headache, backache, and fever up to 40 °C, all beginning abruptly. Then a rash appears on the face and spreads, the spots become watery blisters containing pus that form scabs and leave pitted scars when they fall off. The infected person is contagious until the last smallpox scab has fallen off, although most of the transmission occurs in the first week. Most people with smallpox recover, but some do die and the risk depends on the strain of virus." In 1980, the World Health Organization certified that the naturally occurring smallpox disease was eradicated. According to the FDA, "Until ACAM2000 was licensed, Dryvax, manufactured by Wyeth Laboratories, Inc., was the only vaccine licensed by FDA. Routine vaccination of the American public was stopped in 1972 after the disease was eradicated from the United States. However, smallpox has the potential to be deliberately used as a weapon by terrorists. A large proportion of the population has no immunity and fatality rates could be higher than 25% if smallpox were to be released as a bioterrorist weapon."