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What is Which of the following dengue sequential serotypes infection are associated with maximum risk of dengue hemmorhagic fever? and explain in detail?
Studies in Thailand have revealed that the DENV-1/ DENV-2 sequence of infection was associated with a 500 fold risk of DHF compared with primary infection. For the DENV-3/DENV-2 sequence the risk was 150-fold, and a DENV-4/DENV-2 sequence had a 50-fold risk of DHF. There is no time-limit to sensitization after a primary infection. The 1997 Santiago de Cuba epidemic clearly demonstrated that with the introduction of DENV-2, DHF had occurred 16-20 years after the primary infection with DENV-1.