 |
 |
| DISSS Home | Contact Us |
| ||||||||
|
|
|
|
|
|
| ||
|
|
| ||||||
.gif){kind=spacer} 
|
|
|
|||||||||||||||||||||||||||||||||||||||
|
|
||||||||||||||||||||||||||||||
|
| ||||||||||||||||||||||||||||||
Clinical Case Definition
An illness with acute onset of fever ≥101º F ( ≥38.3 º C) followed by a rash characterized by firm, deep seated vesicles or pustules in the same stage of development without other apparent cause. Clinically consistent cases are those presentations of smallpox that do not meet this classical clinical case definition: a) hemorrhagic type, b) flat type, and c) variola sine eruptione. (Detailed clinical description is available on the CDC web site, see URL: http://www.bt.cdc.gov/agent/smallpox/index.asp).
Laboratory Criteria
Polymerase chain reaction (PCR) identification of variola DNA in a clinical
specimen,
OR
Isolation of smallpox (variola) virus from a clinical specimen (Level
D laboratory only; confirmed by variola PCR).
Note: Indications for laboratory testing of patients with suspected smallpox should be followed as described in detail in Guide A of the CDC Smallpox Response Plan. Laboratory diagnostic testing for variola virus should be conducted in Level C or D laboratories only.
Case Classification*
Confirmed: case of smallpox that is laboratory confirmed, or a case that meets the clinical case definition that is epidemiologically linked to a laboratory confirmed case.
Probable: A case that meets the clinical case definition, or a clinically consistent case that does not meet the clinical case definition and has an epidemiological link to a confirmed case of smallpox.
Suspected: A case with a generalized, acute vesicular or pustular
rash illness with fever
preceding development of rash by 1-4 days.
*Exclusion Criteria: A case may be excluded as a suspect or probable smallpox case if an alternative diagnosis fully explains the illness or appropriate clinical specimens are negative for laboratory criteria for smallpox.
Note: The smallpox case definition is to be used only
during post-event surveillance. The case definition described in Guide
A of the Smallpox Response Plan and Guidelines (Version 3) on the CDC
bioterrorism preparedness website (URL: http://www.bt.cdc.gov/agent/smallpox/response-plan/index.asp)
includes different criteria for a suspected case than the smallpox case
definition the Council of State and Territorial Epidemiologists approved
for use in the National Notifiable Diseases Surveillance System (NNDSS).
The smallpox case definition on the CDC bioterrorism web site is more
sensitive and less specific than the case definition for the NNDSS, in
that a "suspect" case is defined as: "a case with febrile rash illness
with fever preceding the development of rash by 1-4 days."
 |
|
|
|
|
Privacy Policy | Accessibility CDC Home | Search | Health Topics A-Z This page last updated January 9, 2008 United States
Department of Health and Human Services "Epi Info" is a trademark of the Centers for Disease Control and Prevention (CDC). |
