<s>[INST] What percentage of pneumonia is caused by viruses? [/INST] 50% are caused by viruses and are less severe than bacteria. Symptoms are milder than bacterial pneumonia like cold, dry cough, headache, fever and weakness. Source: MedIndia. Link: https://www.medindia.net/patients/patientinfo/pneumonia-faq.htm. Field: Lung Disease. Disease: Pneumonia </s>