The main differences between viral and bacterial colds are: First, the pathogens are different. Viral colds are primarily caused by viruses, while bacterial colds are mainly caused by bacterial infections. Second, the characteristics of contagion differ. Viral colds generally have stronger contagiousness, such as influenza, which has distinct characteristics of outbreaks and often occurs seasonally in spring and winter, with a sudden onset. Bacterial colds are less contagious and typically occur sporadically. Third, the symptoms differ. Generally, viral colds mainly present symptoms of nasal congestion, runny nose, and other upper respiratory catarrhal symptoms. Bacterial colds mainly present with fever, sore throat, tonsillitis, and other symptoms. Fourth, in terms of examinations, a typical hemogram for viral colds usually shows normal or low white blood cells, with an increase in lymphocytes, while bacterial colds often show an increase in white blood cells or neutrophils. Fifth, the treatment approaches differ. Treatment for viral colds primarily includes antiviral therapy, nutritional support, ventilation, and hydration. Bacterial colds are mainly treated with antibiotics and anti-infection therapies.