What does getting dengue fever mean in the long run?

Worse next time. There are 4 serotypes (varieties) of dengue virus. Most people recover uneventfully. Rarely, some have internal oozing which can be very serious. Oddly enough, if you have been infected with one variety in the past, you are more likely to have a severe reaction to another dengue serotype infection in the future. Prevention is essential: wear insect repellent during the day.