Parainfluenza

Parainfluenza is an acute viral inflammation of the airways beginning as laryngitis. With a more severe course, it progresses to bronchopneumonia. It is caused by different serotypes of the parainfluenza virus, which belong to paramyxoviruses and are transmitted by droplets. It typically occurs seasonally (autumn, spring) and mainly affects children under two years of age. A serious acute complication is airway obstruction due to inflammatory laryngeal edema.

Course of disease
The incubation period lasts 2-6 days. Then the infection starts with sore throat and high fever. Sometimes the first symptoms are accompanied by a characteristic barking cough. Heavier forms with subglottic obstruction are manifested by inspirational stridor with retraction of the jugular pits. Parainfluenza virus serotypes 1 and 2 (abbreviated HPIV-1/2 from human parainfluenza virus) are therefore among the major causative agents. In contrast, HPIV-3 causes lethal pneumonia in immunosuppressed or malnourished children in less developed countries.

Diagnosis and therapy
Direct confirmation of the virus after its cultivation and indirect serology by detection of specific antibodies can be used to confirm the diagnosis. We also detect the virus by PCR or immunofluorescence. Due to subsequent therapy, parainfluenza should be distinguished from haemophilic epiglottitis, whooping cough and diphteria. Foreign body aspiration is also considered as a differential diagnosis.

Causal therapy is not yet possible and there is no vaccination against parainfluenza. Symptomatic therapy mainly includes oxygenation, rehydration and, in addition, airway corticoids with sedatives. ATB therapy is initiated in a secondary bacterial infection.

Reference

 * Influenza
 * Paramyxovirus
 * Acute obstructive laryngitis
 * Acute laryngitis

Source

 * ws:Parainfluenza