A small addendum in response to the above. Travelers should be advised that NO Chemoprophylaxis regimen is completely effective and that prompt medical evaluation should be sought for all febrile illnesses.
IN REGARD TO THE RECOMMENDATION OF QUININE let me only state this. Blackwater fever is a rare complication of malaria characterized by intravascular hemolysis and hemoglobinuria. It occurs, perhaps exclusively, in chronic falciparum malaria, ESPECIALLY IN PATIENTS TREATED WITH QUININE. Also, QUININE and its synthetic substitutes produce a permanent loss of hearing.
Medication can create it's own problems and can be dangerous when taken without the advice of a physician. In the DR and many other countries, medications ( and dangerous medications) can be obtained over the counter with out a prescription or advice of a physician. Just did not want anyone running out and getting a "little" quinine just in case.