Letter to the Editor: Incidence of primary dengue viral infection in healthy adults of Rawalpindi, Pakistan

Madam, dengue viral infection (dvi) is a global health problem, infecting about 50-100 million people annually. more than 2.5 million cases have dengue haemorrhagic fever (dhf) and dengue shock syndrome (dss). female aedes aegypti mosquito is the principle vector. a primary dengue infection results from the first exposure with only one of the four den serotypes. it is seen in those who are not immune to the flaviviruses. the cross reacting antibodies formation in the secondary phase leads to dhf and dss. in the absence of specific therapeutic measures, the mortality rate with dhf and dss is 5%.