The Lancet
May 03, 2014 Volume 383 Number 9928 p1521 – 1608
http://www.thelancet.com/journals/lancet/issue/current
Comment
Variola virus archives: a new century, a new approach
Peter B Jahrling, Owale Tomori
Full Text |
Eradication of smallpox was the signature public health achievement of the 20th century—the result of relentless collective action by the global community. Although the disease is long gone, variola virus, which causes smallpox, still exists in two WHO-approved laboratories.1

Incidence of multidrug-resistant tuberculosis disease in children: systematic review and global estimates
Helen E Jenkins PhD a, Arielle W Tolman BA b, Courtney M Yuen PhD b, Jonathan B Parr MD a b c, Salmaan Keshavjee MD a b c, Carlos M Pérez-Vélez MD c d, Prof Marcello Pagano PhD e, Dr Mercedes C Becerra ScD a b c†, Ted Cohen MD a f
Summary
Background
Multidrug-resistant tuberculosis threatens to reverse recent reductions in global tuberculosis incidence. Although children younger than 15 years constitute more than 25% of the worldwide population, the global incidence of multidrug-resistant tuberculosis disease in children has never been quantified. We aimed to estimate the regional and global annual incidence of multidrug-resistant tuberculosis in children.
Methods
We developed two models: one to estimate the setting-specific risk of multidrug-resistant tuberculosis among child cases of tuberculosis, and a second to estimate the setting-specific incidence of tuberculosis disease in children. The model for risk of multidrug-resistant tuberculosis among children with tuberculosis needed a systematic literature review. We multiplied the setting-specific estimates of multidrug-resistant tuberculosis risk and tuberculosis incidence to estimate regional and global incidence of multidrug-resistant tuberculosis disease in children in 2010.
Findings
We identified 3403 papers, of which 97 studies met inclusion criteria for the systematic review of risk of multidrug-resistant tuberculosis. 31 studies reported the risk of multidrug-resistant tuberculosis in both children and treatment-naive adults with tuberculosis and were used for evaluation of the linear association between multidrug-resistant disease risk in these two patient groups. We identified that the setting-specific risk of multidrug-resistant tuberculosis was nearly identical in children and treatment-naive adults with tuberculosis, consistent with the assertion that multidrug-resistant disease in both groups reflects the local risk of transmitted multidrug-resistant tuberculosis. After application of these calculated risks, we estimated that around 999 792 (95% CI 937 877—1 055 414) children developed tuberculosis disease in 2010, of whom 31 948 (25 594—38 663) had multidrug-resistant disease.
Interpretation
Our estimates underscore that many cases of tuberculosis and multidrug-resistant tuberculosis disease are not being detected in children. Future estimates can be refined as more and better tuberculosis data and new diagnostic instruments become available.
Funding
US National Institutes of Health, the Helmut Wolfgang Schumann Fellowship in Preventive Medicine at Harvard Medical School, the Norman E Zinberg Fellowship at Harvard Medical School, and the Doris and Howard Hiatt Residency in Global Health Equity and Internal Medicine at the Brigham and Women’s Hospital.

Viewpoint
Importance of tuberculosis control to address child survival
Stephen M Graham, Charalambos Sismanidis, Heather J Menzies, Ben J Marais, Anne K Detjen, Robert E Black
Tuberculosis commonly affects young children (<5 years) in countries that have high rates of child mortality.1 The global public health focus to control tuberculosis has traditionally aimed to reduce transmission through early case-finding and effective treatment of the most infectious cases. Young children have historically been excluded from this focus, since their contribution to tuberculosis transmission is believed to be small. In the past decade, national tuberculosis programmes in high-burden settings have given increased attention to the challenges of childhood tuberculosis.