Cytomegalovirus immunoglobulin G avidity index among blood donors in Alexandria, Egypt

Abstract

Background and Aim: Transfusion transmitted diseases (TTD) are a major challenge to transfusion services all over the world. Cytomegalovirus (CMV) is considered one of the main viruses associated with blood transfusion. As CMV screening is not included in routine screening tests done for donated blood in blood banks in Egypt, the detection of CMV Immunoglobulin G (IgG) avidity needs to be tested for being a useful tool to diagnose recent infection among blood donors. The aim of this work was to study CMV IgG avidity index (AI) among blood donors. Methods: A total of 88 blood samples were collected from the non-remunerated volunteer blood donors who attended the Alexandria Regional Blood Transfusion Centre. A quantitative enzyme linked immunosorbent assay for the avidity detection of the specific IgG antibodies to CMV in human serum samples was used. Results: Eighty five studied blood donors (96.6%) were positive for CMV IgG. Eighty one donors (95.3%) showed high avidity (>45.0%). Regarding the remaining four CMV IgG positive donors; three had medium avidity (<45.0%) and only one had a low avidity of <25.0%. A moderate agreement of 42.4% was found between IgG concentration and avidity. Conclusions: CMV seroprevalence was found to be high among volunteer blood donors, where age and gender were statistically significant factors associated with CMV IgG concentration. The use of the avidity assay as a screening tool for CMV among blood donors is highly suggested. The exclusion of the low and medium AI units will ensure the availability of a safe stock of blood units, hence eliminating the risk of CMV transmission to vulnerable groups.