Personally I have found this herb is excellent for viral infections, including chronic viral infection.
Supplement brief Elderberry
Natural Health
Inhibition of Several Srrains of Influenza Virus in Vitro and Reduction of Symptoms by an Elderberry Extract (Sambucus nigra L.) during an Outbreak of Influenza B Panama
The Journal of Alternative and Complementary Medicine
Recover from the Flu in Half the Time
ElderberryAre there any side effects or interactions?
www.mothernature.com
Beyond Nerves
Nature Medicine, November 2003, Vol. 9, No. 11
A Bitter Remedy That Brings Sweet Relief
Alternatives, Oct. 2001
Elderberry, Flu Contrary / Growing Older With Elderberry / Sambucus Blackberry Extract
Hadassah Magazine / Vitamin Retailer
5 Essential Healing Herbs
Herbs for Health September /October 2002 Pg 32