Three questions to Dr. Jacques Labescat, phytotherapist, homeopath. He gives lots of advice ... Who are the most vulnerable people? Children with asthma or who have sensitive bronchi. Then all people who have lung problems, recurrent infections. For example, those who are in chemotherapy. Finally, the elderly whose immune defenses are weak, because they are often deficient in trace elements, these minerals essential to the proper functioning of the body, and immunity in particular