Incidence of lambliasis in the child population of an urban district

: A study was carried out on the infestation with Giardia lamblia in 9316 children within the district served medically by the Titan University Polyclinic, in 1976. The mean annual infestation was 13.1% with slight monthly differences, except September and October when the proportion of children with G. lamblia exceeded 16%. The infestation was of 4.1% in the 0--1 year age-group, reaching a peak of 16.8% in the 3--5 years age-group, then gradually falling to 6.3% after the age of 14 years. In September and October the incidence increased to 16.9% and 16.4% respectively, but it should be emphasized that in the sick children referred for medical treatment during this period the incidence of infestation was within the mean monthly values for 1976, whereas in the children without clinical symptoms, examined for admission to children's communities, the infestation index rose to 19%. The fact that infestation with G. lamblia is greater in healthy than in sick children renders the control of giardiasis more difficult.