Some people are fatigued or tired for months after Epstein-Barr virus infection. It's best to avoid contact sports for 6 to 8 weeks after the appearance of symptoms as a blow to the abdomen could damage or burst an enlarged spleen. EBV may be present in the saliva for up to 18 months after infection. A person who has symptoms for more than 6 months is said to have chronic EBV infection