Study aim: Effect of Cinnamase drops on the incidence of clinical symptoms in asymptomatic individuals in the family of under treatment Covid 19 patients Design: The present study is a randomized controlled clinical trial involving two groups of intervention and control which is performed in parallel, non-blind, randomized groups by SAS9.4 software on 100 patients. Settings and conduct: The study site is Kian Asai Pars Health Promotion and Prevention Center. By examining the PCR test, after a visit by a physician, individuals with the inclusion criteria complete an informed consent form. According to the table of random numbers, the intervention group received Cinnamaz drops and the control group did not receive medication. At the end of the intervention in the first week and second week, participants will be monitored for clinical symptoms and COVID-19. and a questionnaire approved by infectious and lung diseases researchers is completed for both groups Participants/Inclusion and exclusion criteria: Inclusion criteria for participants are: Definitive diagnosis of Covid 19 for a member of family based on clinical symptoms and positive PCR ‎test result; Signing an informed consent form; No symptoms of Covid 19 from two weeks before the study; Do not participate in other clinical trials and exclusion criteria is allergy to herbal medicines and natural oils. Intervention groups: Intervention group: 50 healthy persons in contact with the Covid-19 patient use one drop of ‎Cinnamase ‎oil (License number: 118880/665, the product of ‎‎"Sanabel Daroo" company, prepared from Nigella sativa L. oil and ‎Olea europaea L oil.) in each side of their nose twice a day for 7 days. Control group: 50 healthy persons in contact with the Covid-19 patient do not take any complementary therapy during the study. Main outcome variables: Clinical signs of coronavirus disease