Incubation period of diphtheria:

Ans. (a) 2-3 daysRef: Harrison's 18th ed. Ch 138Harrisons states: "The incubation period for respiratory diphtheria is 2-5 days; however, disease can develop as long as 10 days after exposure"Types of Diphtheria Infections are1. Faucial (tonsillar pharyngeal)- Commonest type, grey with white pseudomembrane and cervical lymphade- nopathy (bull neck) + toxemia2. Laryngeal - Most severe form3. Nasal - Mildest form4. Cutaneous form - Only non toxigenic strain, punched- out ulcer5. Other form - Conjuctival, otic, genital