The study was carried out in Ciudad Bolivar, located in the Bolivar state, southern Venezuela, at 54 m above sea level, covering an area of 209.5 km2 and an average temperature of 27.7 °C. Ciudad Bolivar has a population of approximately 567,000 inhabitants. In Bolivar state, 70–80% of malaria cases are caused by Plasmodium vivax, and 20–30% are due to Plasmodium falciparum [21]. Recently, it has been reported that municipalities in Bolivar state have a heterogeneous annual parasitic incidence (API), with some hotspots in the southeast part [23]. For epidemiological week N° 52 of 2016, the API was 101.7 per 1000 inhabitants in this state [24]. The main hospital in the region is the “Ruíz y Páez” University Hospital Complex, an academic hospital attending patients referred from other hospitals.