Rubella is a mild contagious viral infection mainly affecting the skin and lymph nodes causing a pinkish-red rash. It first appears on the face than elsewhere on the body. The infection usually lasts for 2 to 3 days and then naturally wears off. The infection is also known as German Measles or 3-day measles. The Rubella test is used to detect antibodies in the blood that develop in response to a rubella infection. A rubella test may be ordered for a person experiencing symptoms of mild fever, runny or stuffy nose, swollen lymph nodes and pinkish red rashes on the face initially followed by the arms, legs and elsewhere on the body or to a woman pregnant. There are two types of rubella antibodies that a lab test can detect: IgM and IgG. The first type of antibodies appears in the blood after the exposure to IgM rubella antibody. In this case, the level of protein rises and peaks in the blood within about 7 to 10 days after infection and then it tapers off in the next few weeks. However, if a newborn is affected it may be detected for several months to a year.