Yes, if good quality. A large number of studies show that good-quality echinacea products can boost immune function, esp. What is called non-specific immunity, by enhancing function of macrophages, neutrophils & natural killer cells. Some of the studies are inconsistent but this may be due to the fact that not all echinacea products are of good quality. See http://www. Nottingham. Ac.Uk/burn/parker. Pdf for a good review.
Maybe. Many people are looking for some "magic pill" to "boost their immune system". There is no such pill. However, there is a way to boost your immune system, live a healthy lifestyle. Proper diet, proper sleep- wake cycles, healthy environment, proper exercise are the foundation of good health and good immune health. Echinacea when used short term can increase immune response, caution with autoimmune.