Children are at increased risk of rapid progression to active disease (usually within a year for infants). , Malnutrition has been identified as a major risk factor for progression to TB because of its profound effect on cellular immune function- the key host defence against TB. There are 2 types of risk associated with malnutrition: acquisition of infection and risk of infection progressing to disease. Therefore, in populations with high prevalence of latent TB infection, co-prevalent malnutrition may influence TB incidence rates.