Post-eradication vaccination
Smallpox vaccination lesion, ten days after vaccination.
The vaccine consists of the virus which causes the related, yet far milder, cowpox disease; this virus is appropriately named vaccinia, from the Latin vaca which means cow. This vaccine has functional viruses in it which improves its effectiveness but, unfortunately, causes serious complications for people with impaired immune systems (for example chemotherapy and AIDS patients, and people with eczema) and is not yet considered safe for pregnant women. A woman planning on conceiving within one month should not receive the smallpox immunization until after the pregnancy. In the event of an outbreak the woman should delay pregnancy if possible. A small, yet significant, percentage of healthy individuals also suffer adverse side-effects which, in rare cases, include permanent neurological damage. Vaccines that only contain attenuated vaccinia viruses (an attenuated virus is one in which the pathogenicity has been decreased through serial passage) have been proposed but some researchers have questioned the possible effectiveness of such a vaccine. According to the Centers for Disease Control and Prevention CDC, "vaccination within 3 days of exposure will prevent or significantly lessen the severity of smallpox symptoms in the vast majority of people. Vaccination 4 to 7 days after exposure likely offers some protection from disease or may modify the severity of disease." This, along with vaccinations of so-called first-responders, is the current plan of action being devised by the United States Department of Homeland Security (including FEMA, now part of DHS) in the United States.
[edit on 31-8-2009 by 12.21.12]
