* patients with pre-existing conditions or demographic features placing them at increased risk of complications from covid10 infection will not be included in this study. these will be considered exclusion factors, thus individuals will be questioned as to the presence or these factors during their telephone screening. * respiratory disorders: * asthma, pre-existing copd, bronchiectasis or cystic fibrosis * hypertension * cardiovascular disease: * rhythm disturbances, recent (less than 6 months), angina pectoris cardiac insufficiency * diabetes * immunosuppressed patients (other than covid-19 induced) * primary immune deficiencies such as hypogammaglobulinemia or common variable immune deficiency (cvid) * chemotherapy depressing the immune system * immune suppressing medications such as prednisone, imuran, or tnf inhibitors, or anti-rejection transplant drugs. * solid organ transplant * cancer under treatment or within five years (except basocellular skin cancers) * pregnant or breastfeeding women or women unwilling to practice contraception as outlined in the study protocol for the duration of the study period. * allergy to milk or its derivatives

* patients with pre-existing conditions or demographic features placing them at increased risk of complications from covid10 infection will not be included in this study. these will be considered exclusion factors, thus individuals will be questioned as to the presence or these factors during their telephone screening. * respiratory disorders: * asthma, pre-existing copd, bronchiectasis or cystic fibrosis * hypertension * cardiovascular disease: * rhythm disturbances, recent (less than 6 months), angina pectoris cardiac insufficiency * diabetes * immunosuppressed patients (other than covid-19 induced) * primary immune deficiencies such as hypogammaglobulinemia or common variable immune deficiency (cvid) * chemotherapy depressing the immune system * immune suppressing medications such as prednisone, imuran, or tnf inhibitors, or anti-rejection transplant drugs. * solid organ transplant * cancer under treatment or within five years (except basocellular skin cancers) * pregnant or breastfeeding women or women unwilling to practice contraception as outlined in the study protocol for the duration of the study period. * allergy to milk or its derivatives

- patients with pre-existing conditions or demographic features placing them at increased risk of complications from covid10 infection will not be included in this study. these will be considered exclusion factors, thus individuals will be questioned as to the presence or these factors during their telephone screening. - respiratory disorders: - asthma, pre-existing copd, bronchiectasis or cystic fibrosis - hypertension - cardiovascular disease: - rhythm disturbances, recent (less than 6 months), angina pectoris cardiac insufficiency - diabetes - immunosuppressed patients (other than covid-19 induced) - primary immune deficiencies such as hypogammaglobulinemia or common variable immune deficiency (cvid) - chemotherapy depressing the immune system - immune suppressing medications such as prednisone, imuran, or tnf inhibitors, or anti-rejection transplant drugs. - solid organ transplant - cancer under treatment or within five years (except basocellular skin cancers) - pregnant or breastfeeding women or women unwilling to practice contraception as outlined in the study protocol for the duration of the study period. - allergy to milk or its derivatives

- patients with pre-existing conditions or demographic features placing them at increased risk of complications from covid10 infection will not be included in this study. these will be considered exclusion factors, thus individuals will be questioned as to the presence or these factors during their telephone screening. - respiratory disorders: - asthma, pre-existing copd, bronchiectasis or cystic fibrosis - hypertension - cardiovascular disease: - rhythm disturbances, recent (less than 6 months), angina pectoris cardiac insufficiency - diabetes - immunosuppressed patients (other than covid-19 induced) - primary immune deficiencies such as hypogammaglobulinemia or common variable immune deficiency (cvid) - chemotherapy depressing the immune system - immune suppressing medications such as prednisone, imuran, or tnf inhibitors, or anti-rejection transplant drugs. - solid organ transplant - cancer under treatment or within five years (except basocellular skin cancers) - pregnant or breastfeeding women or women unwilling to practice contraception as outlined in the study protocol for the duration of the study period. - allergy to milk or its derivatives