Rubella
It is often mild and an attack can pass unnoticed. However, this can make the virus very difficult to diagnose. The virus usually enters the body through the nose or throat. Children recover more quickly than adults. Like most viruses living along the respiratory tract, it is passed from person to person by tiny droplets in the air that are breathed out. Rubella can also be transmitted from a mother to her developing baby through the bloodstream through the placenta. The virus has an incubation period of 2 to 3 weeks during which it becomes established.