Those who already had dengue can only be reinfected with a different serotype. The health situation is complicated week by week, with a vaccine that for now is accessed by the few who can pay for it.
Aedes aegypti mosquitoes, which transmit the virus, are the main source of the disease. It is possible to approximate the probability that an infected mosquito will infect a person who has already had the disease by biting it, says Dr. Ruben Navarrette.