Correspondence

Historical declines in tuberculosis: nature, nurture and the biosocial model. P. DÕArcy Hart, MD, FRCP, FMedSci, MRC (Medical Research Council), National Institute for Medical Research, The Ridgeway, Mill Hill, London, UK

DOTS and DOTS plus: whatÕs in a name. A. Aerts, International Committee of the Red Cross, Health Services Unit, 19 Avenue de la Paix, 1202 Geneva, Switzerland; and R. de Haller, International Committee of the Red Cross, Health Services Unit, 19 Avenue de la Paix, 1202 Geneva, Switzerland

In reply. Kitty Lambregts, KNCV, The Hague, The Netherlands; and Lee Reichman, New Jersey Medical School, National Tuberculosis Center, Newark, NJ, USA

Efforts of the WHO/IUATLD to solve the problem of poor bioavailability of rifampicin from FDC anti-tuberculosis products: is a change required in the direction of the approach in view of recent findings?. Saranjit Singh, MD, Department of Pharmaceutical Analysis, NIPER, S.A.S. Nagar, INDIA

Free mediastinal air on chest CT scan: a diagnostic feature of esophageal tuberculosis in human immunodeficiency virus infection. Catherine Fleming, MD, MPH, Department of Infectious Disease, Boston University School of Medicine, Boston, MA, USA; John Bernardo, MD, The Pulmonary Center, Boston University School of Medicine, Boston, MA, USA; and Anthony OÕRegan, MD, The Pulmonary Center, Boston University School of Medicine, Boston, MA, USA