Active tuberculosis among Iraqi schoolchildren with positive skin tests and their household contacts

ABSTRACT

In a prospective cohort study in Iraq, schoolchildren with a positive tuberculin skin test during the nationwide survey in 2000 were followed up in 2002 to determine prevalence of latent tuberculosis [TB] infection and risk factors among household contacts. Of 205 children, 191 remained skin-test positive in 2002. Based on X-ray and clinical examination, 9 children [4.4%] were active TB cases. Among 834 household contacts, there were 144 new TB cases, giving a cumulative incidence of 17.3%. Risk factors for TB among household contacts were age > / = 15 years; technical/professional job; smoking; low body mass index; diabetes mellitus; steroid therapy; and closeness of contact with the index cases. Based on past history of TB in index children and their contacts, 77.2% of new TB cases were attributable to household contacts