Which age group is most commonly affected by mononucleosis?

Mononucleosis, often called "mono," is a viral infection most commonly associated with the Epstein-Barr virus (EBV). The age group most frequently affected ranges from adolescents to young adults, typically between 15 to 35 years. During this period, individuals are more likely to engage in activities that increase the risk of transmission, such as sharing drinks or engaging in close social interactions.

The symptoms of mononucleosis tend to manifest more severely in this age group, likely due to the immune response at play during these years. While younger children can contract the virus, they often exhibit milder symptoms or are asymptomatic. Conversely, older adults, particularly those over 36, generally have a lower incidence of mononucleosis, as they are less likely to encounter the virus in their social circles and often have developed immunity due to earlier exposure.

Thus, the age range of 15 to 35 years stands out as the group most affected by mono, making it the correct choice in understanding the demographics of this infection.