Question:
Does immunity against Dengue last for only a year?
Answer:
All of the literature on the subject clearly state that infection with any one of the four Dengue virus types (there are four distinct serotypes, Den-1, Den-2, Den-3 and Den-4) offers LIFELONG immunity. However, immunity with one type has the uncanny potential to exacerbate a second infection with a different virus. This is what leads to Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS), complications that increase your chances of death by 3-4%.
According to the National Biological Information Infrastructure the West Nile virus (WNV) was first detected in the Western Hemisphere in 1999 and has since rapidly spread across the North American continent into all 48 continental states, seven Canadian provinces, and throughout Mexico. In addition, WNV activity has been detected in Puerto Rico, the Dominican Republic, Jamaica, Guadeloupe and El Salvador. (Source: http://www.mommypr.com/?p=8450)
