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A Parotid salivary gland
Mumps is a viral disease caused by a Paramyxovirus which is a member of the Rubulavirus family.The onset of the disease is marked with a few days of fever, headache, muscle aches, tiredness, and loss of appetite. Most people gradually develop puffy cheeks and a tender, swollen jaw due to the swelling of their parotid salivary glands (located in front and below the ear).
The disease causes pain, tenderness, and swelling in one or both parotid salivary glands. The swelling usually peaks in the first three days and then subsides in the following week. Often, the jawbone cannot be felt because of swelling of the parotid glands. Other salivary glands, submandibular (near the lower jaw) and sublingual (near the floor of the mouth on either side of the tongue) may also swell but the frequency is less. The disease spreads through saliva or respiratory droplets released through coughing, sneezing, talking, etc.
The thyroid is a butterfly shaped endocrine gland located just below the pharynx. It secretes the hormone thyroxine to regulate basal metabolism in the body. It is not affected during mumps.