Safety and Immunogenicity of ChAd63 RH5 and MVA RH5 in Adults, Young Children and Infants Living in Tanzania

Inclusion Criteria: Only participants who meet all the inclusion criteria will be enrolled into the trial; * Group 1: Healthy male or female adults aged 18-35 years at the time of enrolment with signed consent. * Group 1 (Female only participants): Must be non-pregnant (as demonstrated by a negative urine pregnancy test), and provide consent of their willingness to take Depo-Provera contraceptive during the study and safety follow-up period. * Groups 2a \& 2b: Healthy male or female young children aged 1-6 years at the time of enrolment with signed consent obtained from parents or guardians. * Groups 3a \& 3b: Healthy male or female infants aged 6-11 months at the time of enrolment with signed consent obtained from parents or guardians. * Planned long-term (at least 9 months from the date of recruitment) or permanent residence in Bagamoyo town. * Adults with a Body Mass Index (BMI) 18 to 30 Kg/m2; or young children and infants with Z-score of weight-for-age within ±2SD. Exclusion Criteria: The participant may not enter the trial if ANY of the following apply: * Clinically significant congenital abnormalities as judged by the PI or other delegated individual. * Clinically significant history of skin disorder (psoriasis, contact dermatitis etc.), allergy, cardiovascular disease, respiratory disease, endocrine disorder, liver disease, renal disease, gastrointestinal disease and neurological illness as judged by the PI or other delegated individual. * Any confirmed or suspected immunosuppressive or immunodeficient state, including HIV infection; asplenia; recurrent, severe infections and chronic (more than 14 days) immunosuppressant medication within the past 6 months (inhaled and topical steroids are allowed). * History of cancer (except basal cell carcinoma of the skin and cervical carcinoma in situ). * Weight for age z-scores below 2 standard deviations of normal for age. * History of allergic disease or reactions likely to be exacerbated by any component of the vaccines, e.g. egg products, Kathon, neomycin, betapropiolactone. * Any history of anaphylaxis in relation to vaccination. * Clinically significant laboratory abnormality as judged by the PI or other delegated individual. * Blood transfusion within one month of enrolment. * History of vaccination with previous experimental malaria vaccines. * Administration of immunoglobulins and/or any blood products within the three months preceding the planned administration of the vaccine candidate. * Participation in another research study involving receipt of an investigational product in the 30 days preceding enrolment, or planned use during the study period. * Seropositive for hepatitis B surface antigen (HBsAg) or hepatitis C (HCV IgG). * Any other finding which in the opinion of the PI or other delegated individual would increase the risk of an adverse outcome from participation in the trial. * Likelihood of travel away from the study area. * Positive malaria by blood smear at screening. * Female participant who is pregnant, lactating or planning pregnancy during the course of the trial. * Scheduled elective surgery or other procedures requiring general anaesthesia during the trial. * Any other significant disease, disorder or situation which, in the opinion of the Investigator, may either put the participants at risk because of participation in the trial, or may influence the result of the trial, or the participant's ability to participate in the trial.