Clara Maass was a New Jersey native and nurse who died as a direct result of furthering research efforts to control yellow fever. Yellow fever is an infectious disease caused by a virus transmitted by the bite of an infected mosquito. It may occur in a mild form similar to influenza, but in its classical form it is a severe illness. There is no specific treatment. Most victims recover and thereafter have lifelong immunity. The mortality rate is between five and ten percent. In 1901 Walter Reed and his co-workers first demonstrated the relationship of yellow fever to mosquitoes. Efforts to control the disease allowed construction on the Panama Canal to continue. The research led to mosquito control measures that still are the only effective means for preventing yellow fever epidemics.