Epidemiology and clinical presentation of the four human parainfluenza virus types

Liu, Wen-Kuan; Liu, Qian; Chen, De-Hui; Liang, Huan-Xi; Chen, Xiao-Kai; Huang, Wen-Bo; Qin, Sheng; Yang, Zi-Feng; Zhou, Rong

Clinical presentations were collected and categorized retrospectively into the following six groups from the patients' medical records using designed presentation cards: URTI, LRTI, systemic influenza-like symptoms, gastrointestinal illness, neurologic symptom and others. Patients with nasal obstruction, coryza, sneeze, cough, pharyngeal discomfort, or hoarseness were categorized as having URTI. Patients with pneumonia, bronchopneumonia, increasing lung markings, dyspnoea, or abnormal pulmonary breath sound were categorized as having LRTI. Patients with high fever (≥38°C), chills, dizziness, headache, myalgia or debilitation were categorized as having systemic influenza-like symptoms. Patients with vomiting, poor appetite, or diarrhoea were categorized as having gastrointestinal illness. Patients with convulsion were categorized as having an neurologic symptom. Patients with other symptoms, including but not limited to rash, were classified as "others". Some patients were assigned to multiple clinical presentation groups. Pneumonia and bronchopneumonia were diagnosed by chest radiography. Pneumonia was defined as an acute illness with radiographic pulmonary shadowing which was at least segmental or present in one lobe (excluding the bronchi); bronchopneumonia was defined as inflammation of the walls of the smaller bronchial tubes, with varying amounts of pulmonary consolidation due to spread of the inflammation into peribronchiolar alveoli and the alveolar ducts. Other clinical symptoms were identified by common medical examinations and clinical descriptions.