Disease	Source patient's disease status	Status of exposed person	Regimen
Anthrax	No human-to-human transmission	Persons who are unvaccinated or who received the full vaccination series who are exposed to Bacillus anthracis spores from bioterrorism or occupational exposure*	Anthrax vaccine (0.5 mL subcutaneously) at zero, two, and four weeks
			and
			Antibiotic therapy for 60 days: ciprofloxacin (Cipro; 500 mg orally) twice daily or doxycycline (100 mg orally) twice daily or, for pregnant women or children, amoxicillin (500 mg orally) three times daily
Diphtheria	Symptomatic case or asymptomatic carrier	Close contacts regardless of immunization status†	Either Td or Tdap if no documentation of receipt of three-dose primary immunization series, or if last dose of vaccine was given more than five years ago
			and
			One dose of IM penicillin G benzathine (600,000 units if patient is younger than six years; 1,200,000 units if patient is older than six years), or erythromycin (500 mg orally) four times daily for seven to 10 days
Measles	From one day before onset of prodrome until four days after rash resolves	Nonimmune contacts	Pregnant women or immunocompromised persons: a single dose of immune globulin (0.25 mL per kg)
			Others: measles vaccine within three days of exposure
Plague	Persons with pneumonic plague treated for < 48 hours‡	All close contacts (face-to-face within two months)	Doxycycline (100 mg orally) twice daily for seven days
			Children or pregnant women: trimethoprim/sulfamethoxazole (160/800 mg orally) twice daily for seven days