In June 2021, a 7-year-old male without comorbidities from the south of Bahia (northeastern Brazil), residing in a peri-urban area, reported fever, chills, fatigue, headache, myalgia, dyspnea, pallor, apathy, and reduced food intake. Other family members reported similar symptoms. The patient was transferred to a reference hospital for infectious diseases in Salvador/Bahia. The patient presented with pallor, tachycardia, and tachypnea without signs of respiratory distress. A physical examination revealed painless hepatomegaly and splenomegaly. Laboratory tests identified hemoglobin 6.2 g/dL, hematocrit 17.4%, leukocytes 5,820/mm3 and platelets 50,000/microL. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgM rapid test result was positive, although the nasal swab SARS-CoV-2 reverse transcription-quantitative PCR (RT-qPCR) result was negative. 
Although a non-malaria-endemic region, a recent malaria outbreak was confirmed in a rural settlement neighboring the region where the patient and his family resided. A rapid test for malaria was positive for P. vivax, confirmed by microscopy and quantitative PCR (qPCR) after genomic DNA extraction from slides (). A thin blood-smear examination identified 378.3 parasites/microL of blood, parasitemia of half a cross. The patient was initially treated with three doses of intravenous artesunate 2.4 mg/kg/dose every 12 h, then two doses of 2.4 mg/kg/dose daily, followed by oral chloroquine with primaquine, resulting in full recovery.