Whiat Causes Mumps. Its genome is about 15,000 nucleotides in length and contains seven genes that encode nine proteins. Mumps is a viral infection that can cause swelling of the cheeks and jaw.
Mumps is an illness caused by a virus. The mumps virus causes pain and swelling in front of the earlobe, called parotitis. Through infected droplets of saliva that can be inhaled or picked up from surfaces and transferred into the mouth or nose.