Contraindications:
(1) history of an immediate anaphylactic response after a previous administration
(2) history of an immediate anaphylactic response to any vaccine component
(3) encephalopathy within 7 days of previous administration, not explained by another condition
Relative Contraindication:
(1) unstable, progressive neurological problem (defer until stable)
Precautions:
(1) unexplained fever >= 40.5°C (>= 105°F) within 48 hours of a previous vaccine administration
(2) unexplained collapse or shock-like state within 48 hours of a previous vaccine administration
(3) seizures within 3 days of a previous vaccine administration
(4) persistent, inconsolable crying lasting >= 3 hours within 48 hours of a previous vaccine administration
If one or more precautionary conditions are noted, then the vaccine is usually not given unless there is a situation where the benefit outweighs the risk, such as during a serious pertussis outbreak.