infectious diseases
Diphtheria
Transmission
Humans are the only known reservoir forC. diphtheriae. The organism is spread by Respiratory droplets Contact with nasopharyngeal secretions (including from asymptomatic carriers) Contact with infected skin lesions Fomites (rare) A carrier state is common in endemic regions but not in high-income countries. Immunity derived from vaccination or active infection may not prevent patients from becoming carriers; however, most patients who are adequately treated do not become carriers. Patients with clinical illness or asymptomatic carriers may transmit the infection. Poor personal and community hygiene contributes to the spread of cutaneous diphtheria. 