The advisory comes in response to several reports CDC received of cardiac events occurring in people who received smallpox vaccinations. Currently it is unclear whether or not there is any association between smallpox vaccination and other cardiac events.
The International Association of Fire Chiefs is also issuing an addendum to the "Fire Chief's Guide to Smallpox Vaccination" that reflects the CDC advisory.
This exclusion may be removed as more information becomes available. Examples of known cardiac disease are cardiomyopathy, previous myocardial infarction (heart attack), history of angina (chest pains caused by lack of blood flow to the heart) or other evidence of coronary artery disease.
In the civilian vaccination program, 25,645 people were vaccinated as of March 21, 2003. Among civilians vaccinated, seven adverse events of cardiac origin have been reported. These include two cases of myopericarditis, three acute myocardial infarctions and two cases of angina without myocardial infarction.
One of the patients with myocardial infarction died. It is important to note that a small number of deaths following vaccination would be expected to occur by statistical chance alone, given the numbers of people already vaccinated in the civilian program.
There is no clustering of events in time after vaccination. Onsets ranged from two to 17 days after vaccination. In addition, five of those vaccinated have been evaluated for chest pain, but evaluation of these patients to date has not found evidence of cardiac involvement.
For more information, visit the CDC Web site, www.cdc.gov.
