The purpose of this study is to investigate for the broad immunological effects of administering measles vaccine (MV) and diphtheria-tetanus-whole cell pertussis vaccine (DTP) to 9 month old Gambian infants, either alone or together. Effects on vaccine-specific immune responses, innate immunity, and immune memory were studied. The hypothesis is that when MV and DTP are given together there will be more inflammation and this will interfere with generation of immunity to the vaccine and to other non-vaccine related stimuli.