Analysis of data obtained from discrete variables requires the use of specific statistical tests which are different from those used to assess continuous variables (such as cardiac output, blood pressure, or PaO 2) which can assume an infinite range of values.
Primary symptoms of dengue appear three to 15 days after the mosquito bite and include the following: 1  high fever and severe headache, 2  with severe pain behind the eyes that is apparent when trying to move the eyes.
The mosquito becomes infected with dengue virus when it bites a person who has dengue virus in their blood. The person can either have symptoms of dengue fever or DHF, or they may have no symptoms. After about one week, the mosquito can then transmit the virus while biting a healthy person.