1	Tuberculosis in Children and Young Adults Clydette Powell, MD, MPH USAID/Washington CCIH, May 2004
2	Objectives Overview global epidemiology Review available surveillance data and epidemiologic studies Review TB and HIV association Assess data limitations Provide recommendations for future data collection and research
3	Tuberculosis A Global Emergency One third of the world’s population is infected TB kills 5,000 people a day – 2-3 million each year HIV and TB co-infection is producing explosive epidemics Hundreds of thousands of children will become TB orphans this year MDR threatens global TB control
4	Background Tuberculosis (TB) is increasing among adults in many areas TB is major cause of childhood morbidity and mortality worldwide Limited information on epidemiology of TB in children
5	Childhood TB Why neglected? Not considered important in global program or contributing to immediate transmission Not regarded as public health risk Difficult to diagnose Why is it important? Health problem in children May later contribute to epidemic
6	Leading Infectious Disease Causes of Death, 1998
7	TB in Children WHO estimate of TB in children 1.3 million annual cases 450,000 deaths 15% of TB in low-income countries children vs. 6% in United States
8	Childhood TB as Sentinel Event Indicates recent transmission in a community Rapid progression from infection to disease “A deterioration in the control of TB thus immediately hurts the youngest generation” (Rieder, 1997) Children are future reservoir of disease
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12	Risk Factors for TB - U.S. Racial/ethnic minorities Foreign-born children or children of immigrant families Internationally adopted children Children traveling overseas Poverty and crowding Contact with infectious adult case
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14	Risk of Progression to Disease Age 43% in infants (children < 1year) 25% in children aged one to five years 15% in adolescents 10% in adults Recent Infection Malnutrition Immunosuppression, particularly HIV
15	Challenges for Surveillance Difficult diagnosis of childhood TB Lack of standard case definition Increased extrapulmonary disease Low public health priority of childhood TB
16	WHO Estimated Total Cases by Age, 2000
17	WHO Estimated Total Cases by Age, 2000
18	Childhood TB in Malawi Retrospective study of 43 hospitals using National TB Data from 1998 2739 cases in children (11.9%) 1.3% smear-positive, 21.3% smear-negative, 15.9% extrapulmonary Poor outcomes 45% completed treatment 17% died 13% default 21% unknown
19	Active Case Finding of TB Meningitis South Africa study among children < 15 years Only 56% of cases were registered 16% of all cases in register contained errors Incorrect diagnosis, double notification, clerical error
20	Extrapulmonary TB in Children Proportion in a given country could be used as measure of case detection 25-44% of all childhood TB in Ugandan study 43% of children in Ethiopian study 21.3% of childhood TB using US surveillance data
21	TB and BCG Vaccination Efficacy for adult pulmonary TB 0-80% in randomized clinical trials Best efficacy against serious childhood disease 64% protection against TB meningitis 78% protection effect against disseminated TB BCG important for young children, inadequate as single strategy
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23	TB/HIV Coinfection in Children 11-64% of children with TB are coinfected with HIV in published studies 1-12% of children with AIDS in autopsy studies found to have TB Other lung disease in children with HIV common Difficulty of confirming TB in HIV-infected children may result in overdiagnosis and overreporting
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25	Treatment questions Difficult to evaluate true cure Recommended same length of treatment as adults HIV & length of treatment?? Many uncertainties eg pharmakokinetics, treatment of MDR-TB Relapse/re-infection in HIV positive children Mortality?
26	Conclusions Data on trends in childhood TB are limited Consensus needed on common definitions Few epidemiologic studies in children worldwide Additional studies are needed Childhood TB needs to become a priority