If my 1 year old contracts mono, should i be seriously worried?

No.: With mono, the earlier you get it, the better - it's the adolescents that suffer for weeks; the infection is usually very mild in toddlers.

Likely not: Most infants and toddlers have a simple course of fever/declining activity and intake which is mild.Many are never worrisome to end up seeing a doc, and those that do are seldom tested for mono (test is often negative early in the illness). I look on it as a benefit to the kid, since they will be immune when the teens/adulthood comes and can avoid the major effects it has on older patients.