Clinical criteria – all of the following without other apparent cause:
(1) febrile prodrome 1-4 days prior to onset of rash
(1a) fever >= 101°F
(1b) symptoms may include: prostration, severe headache, backache, abdominal pain, vomiting
(2) lesions are deep, firm, well-circumscribed vesicles or pustules
(3) lesions of the rash are at the same stage of development
Patients meeting the clinical criteria should be reported immediately and the patient placed in isolation.
Laboratory criteria for confirmation (performed at Level C or D Laboratories only):
(1) isolation of variola virus from a clinical specimen
(2) polymerase chain reaction (PCR) identification of variola DNA
(3) electron microscopy (EM) identification of variola virus from a clinical specimen
