In humans, coronaviruses cause respiratorytractinfections.
冠状病毒在人体内会引起呼吸道感染疾病。
2
Undernutrition increases the risk of upper respiratorytractinfections and subsequent acute bronchitis, especially in children and older people.
营养不良增加上呼吸道感染的风险从而发生急性支气管炎，特别是儿童和老人。
3
Inflammation of the respiratorytract causes coughing, mucus secretion, aggravation of asthma and chronic bronchitis and makes people more prone to infections of the respiratorytract.