In most underdeveloped countries, the initial contact with Epstein Barr virus (EBV) usually happens in the first decade of life and results in an asymptomatic infection, whereas in developed areas, primary infection in adolescence or adulthood is accompanied by infectious mononucleosis in 50% cases. Although it is generally a harmless passenger, in some individuals, it is associated with B-cell lymphoma. In Argentina, EBV primary infection shows the classical pattern observed in developing populations, given that nearly 70% of patients are seropositive by the age of 2 years. However, EBV association with pediatric Hodgkin and Burkitt lymphoma resembles that observed in developed regions. Concerning diffuse large B-cell lymphoma, our series demonstrated higher EBV association than other adult ones from either developed or underdeveloped countries. Interestingly, the early EBV primary infection observed, characteristic of an underdeveloped population, together with the statistically significant EBV association with patients ≤10 years old demonstrated in all types of lymphoma studied, suggest a relationship between low age of EBV seroconversion and B-cell lymphoma development risk.