Molecular and serological detection of Epstein Barr virus from lymphoma patients in Ethiopia

Background: Epstein Barr Virus (EBV) is an oncogenic human herpes virus infecting most of the global population. EBV is linked to various lymphoid and epithelial malignancies. While the epidemiology of EBV-related lymphomas has been studied in North America, Europe, and Asia, there are no reports on the frequency of the virus in lymphoma patients in Ethiopia. Therefore, the study’s main goal was to determine the molecular and serological detection of EBV in patients diagnosed with different types of lymphoma in Ethiopia. Methods: Viral DNA was extracted from formalin fixed paraffin-embedded (FFPE) tissue blocks, polymorphonuclear cells, and fresh lymph node biopsy samples collected from 305 patients at Tikur Anbessa Hospital in Ethiopia. EBV Viral capsid antigen IgG antibody test was performed to assess the EBV serostatus. Quantitative polymerase chain reaction (qPCR) using primers specific for the EBNA1 open reading frame was performed on all lymphoma cases. Results: 31.6% and 69.4% of the study participants were HL and NHL patients, respectively. EBV DNA was detected in 99% of study participants through real-time quantitative polymerase chain reaction(qPCR) and 96% serologically. 56.3% of the lymphoma patients had a higher EBV viral copy number ( > 10,000 EBV particles/ml). Higher EBV viral load was observed in 59.3% and 54.8% of HL and NHL patients, respectively. From the NHL types, DLBCL had the highest EBV viral load prevalence (67.6%), followed by Burkitt’s lymphoma (50%), CLL/small lymphocytic leukemia (44.9%), and follicular lymphoma (20%) specimens had viral loads > 10,000. Differences between sample type and HIV status were significantly associated with a high EBV viral load. In contrast, age, gender and histologic lymphoma subtypes types were not significantly associated with higher EBV copy number. Conclusion: This work shows a high EBV prevalence among lymphoma patients in Ethiopia and represents the first study in this field that can be utilized as a baseline for future studies. Further studies on viral epidemiology should be done throughout the country and across the region of horn of Africa.