Age-related patterns of cytomegalovirus antibodies accompanying Epstein-Barr virus co-infection

Objective: Cytomegalovirus (CMV) infection is associated with age-related chronic disease, and co-infection with Epstein-Barr virus (EBV) may compound disease risk. We aimed to assess the frequency of CMV infection and its relationship with age among EBV seropositive individuals in an Indigenous Amazonian population. Methods: We report concentrations of CMV and EBV antibodies in dried blood spot samples collected from 157 EBV positive Shuar participants aged 15–86 years (60.5% female) to assess CMV infection rate. We used logistic and linear regression models to examine associations among CMV, EBV, and age, adjusting for sex, geographic region, and body mass index. Results: Nearly two-thirds (63.1%) of EBV seropositive participants were also CMV seropositive. A 1-year increase in age was associated with 3.4% higher odds of CMV infection (OR [95% CI]: 1.034 [1.009–1.064], p =.012), but CMV antibody concentration was not significantly associated with age or EBV antibody concentration among co-infected individuals. Conclusions: Herpesvirus-related immunosenescence may be important to understanding chronic disease risk among Shuar. Future studies should further explore the role of co-infection in shaping age-related changes in immune function.