Table 1.

Comparison of the six infections [5]

Infection	Type of pathogen	Generation time	Degree of immunity	Existence of asymptomatic carrier
Measles	Virus	10–14 days	Strongly immunizing	No
Mumps	Virus	16–26 days	Immunizing	Yes
Rubella	Virus	~18 days	Immunizing	Yes
Varicella	Virus	18–23 days	Immunizing	No
Scarlet fever	Bacteria	10–14 days	Immunizing	Yes
Pertussis	Bacteria	~27 days	Waning immunity	Yes