Mumps is a disease caused by a virus, mainly affecting salivary glands in your body. Virus particles spread through coughing & sneezing. People who are not vaccinated are at high risk of getting infected. Vaccinated people may also get infected but they get milder symptoms & less complications. Symptoms resemble flu like illness but in addition, there is swelling on one or both sides of the face. In complicated cases, virus can infect testes, ovaries & brain. Presence of IgG antibodies against mumps virus indicates previous exposure to the virus through infection or immunization.