Inclusion Criteria:  18-55 years old Zinc protoporphyrin > or equal 40 mmol/mol heme hemoglobin < or equal 109 g/L no malaria no known HIV infection no medical condition that precludes study involvement no iron supplementation 1 week prior to study start no recent tuberculosis infection no vaccination of yellow fever or influenza prior to enrolment not pregnant  Exclusion Criteria:  -