Generally viral colds cause loss or decrease in the sense of smell in some patients, mainly related to the irritation of the throat by viral infections. Viral colds are a common disease, mainly caused by viral infections such as rhinovirus, influenza virus and adenovirus. Since viruses can cause irritation to the patient’s throat, some patients may experience a decreased sense of smell or even a loss of smell. For some people with mild symptoms, the loss of smell may not be obvious. Most people with viral colds will recover on their own and the loss of smell will disappear on its own. If the symptoms do not improve or even get worse, you should consult a doctor in a regular hospital and cooperate with the doctor to improve the examination and standardize the treatment.