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 could lead to Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS), complications that increase your chances of death by 3-4%.
What this means is immunity from one type of Dengue, say Dengue-1, is not transferable to any other type. Consequently, you can potentially get Dengue four times, each time with a different virus. But in the end, you will be completely immunised from the disease.
Remember though, a second infection could kill you, so there.
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Kindly send me details of immunity against dengue fever. I have two questions. 1. If a patient got immunity with any serotype does he or she become resistant to that strain, partially or lifelong. 2. If the patient got infected with one serotype does he get immunity against other serotypes as well.
Kindly reply as early as possible.