Virus-induced fever varies in severity, and some are mild. Most of the common colds and upper respiratory tract infections are caused by viruses, and they usually get better in 3-5 days, and some of them may get better in a week. Some fevers can be cured without medication or injections, drinking more warm water and keeping warm. Most of them will be fine if they are slightly severe and can be treated with antiviral fluids or oral antiviral drugs. However, severe viral patients can cause intracranial infection, which is more common in children. If you have a severe headache or vomiting, or even a severe headache when you do not have a fever, pay attention to the stiffness of your neck. If the neck is stiff, especially in children, an intracranial infection is highly suspected. Because intracranial infections are still more commonly caused by viruses, the prognosis is mostly good, as long as timely medical attention is sought. The prognosis is also generally better with antiviral treatment and the use of dehydrating and brain-protective drugs. However, if prolonged, complications may arise, which may cause sequelae. Some patients may present with coma and convulsions, which take longer to treat when they arrive at the hospital, and the medication is mainly antiviral drugs. In patients with severe viral infections, like influenza and SARS, the body temperature may be low at first, but when the disease is severe there may be a high fever with a temperature of 39°C or more, and a viral infection of the lungs may be fine at first, but later a large area of infection is detected on review. So colds caused by viral infections are generally nothing to worry about in particular, and most have an okay prognosis. However, if the temperature continues to rise, it is recommended to visit a proper hospital.