Case Report| Volume 19, ISSUE 3, 104505, March 2023

Cases of Loiasis Among a Congolese Family: Screening for Loiasis Among Newly Arrived Refugees From Endemic Areas

Published:January 27, 2023DOI:


      • Although not commonly seen in the United States, loiasis is important to consider in primary care settings that care for refugees from West and Central Africa.
      • Understanding diagnosis and treatment basics is key to recognizing loiasis in refugee populations.
      • Loiasis can present nonspecifically and requires high clinical suspicion.


      Loiasis is a parasitic infection caused by the filarial nematode Loa loa within endemic regions of West and Central Africa. These regions include areas co-endemic for other nematode infections. Although loiasis is rarely seen in the United States, primary care providers who regularly see refugees from endemic areas should be aware of its clinical presentation, diagnostic workup, and initial management. Given the challenges of diagnosing loiasis, especially in low-prevalence settings, we present cases of 4 family members, 2 of whom were diagnosed with loiasis, and discuss an approach to screening populations from endemic regions during their initial Refugee Health Examination upon arrival to the United States.


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      Shalini Subbarao, MD, Resident Physician, School of Medicine, University of Virginia, Charlottesville, VA, contact at: [email protected]


      Reagan Thompson, DNP, FNP-C, Family Nurse Practitioner, School of Nursing, Department of Population Health, University of Virginia, Charlottesville, VA.


      Amy Klion, MD, Senior Clinical Investigator, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD.


      Fern R. Hauck, MD, Professor, Department of Family Medicine, University of Virginia, Charlottesville, VA.


      Tania A. Thomas, MD, MPH, Associate Professor, Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, VA.