Pseudocroup – colloquially called croup cough – (synonyms: false croup; laryngitis subglottica; spasmodic laryngotracheitis; stenosing laryngotracheitis; stridulous laryngotracheitis; subglottic laryngitis; ICD-10 J38. 5) refers to laryngitis (inflammation of the larynx) that leads primarily to swelling of the mucosa below the vocal cords (stenosing laryngitis).
Pseudocroup is nowadays called viral croup.
Pseudocroup is usually triggered by parainfluenza viruses 1-4 (especially type 1, up to two-thirds of cases).The parainfluenza virus belongs to the genus of paramyxoviruses.Other possible triggers are mainly RSV viruses (respiratory syncytial virus) and bocaparvovirus (until 2015 bocavirus), rhinoviruses and enteroviruses.
Humans are the reservoir of the pathogens, which primarily affect infants from six months to three years of age, with an infection rate of over 90% by the age of ten.
The infection occurs mainly in temperate climates.
Seasonal accumulation of the disease: Pseudocroup occurs more frequently during the cooler months of the year.
Transmission of the pathogen (route of infection) is aerogenic via droplet infection.
The pathogen enters the body parenterally (the pathogen does not enter via the intestine), i.e. in this case it enters the body via the respiratory tract (inhalation infection).
Human-to-human transmission: Yes
Incubation period (time from infection to onset of disease) is usually a few days.
Sex ratio: Boys are affected slightly more often than girls (1.4: 1).
Frequency peak: The maximum incidence of pseudocroup is in infancy.
The prevalence (disease frequency) is up to six percent.
Course and prognosis: The course is usually short. No permanent local (site) damage is expected from the infection. However, damage may occur indirectly due to hypoxemia (oxygen deficiency).Symptoms of the disease pseudocroup usually do not last longer than 1-2 nights. Fever rarely occurs. If fever and symptoms persist, it is suspected that it may be a bacterial superinfection (secondary infection by bacteria).
The disease does not lead to immunity.
Vaccination against pseudocroup is not available.