Upper Respiratory Tract Infections (URIs) are common illnesses that affect the nose, throat, and sinuses. They are often caused by viruses, such as the common cold or influenza, and can lead to symptoms like a runny nose, sore throat, cough, and sneezing. URIs are usually mild and resolve on their own within a week or two. While most URIs are viral, some can be caused by bacteria, leading to conditions like sinusitis or strep throat. Treatment typically focuses on relieving symptoms, such as using decongestants or pain relievers. Good hygiene practices, like handwashing, can help prevent the spread of these infections.