Epidemiology and Infection


Assessing spatiotemporal patterns of multidrug-resistant and drug-sensitive tuberculosis in a South American setting

H. LINa1a2a3, S. SHINa1a4a5, J. A. BLAYAa5a6, Z. ZHANGa1, P. CEGIELSKIa7, C. CONTRERASa8, L. ASENCIOSa9, C. BONILLAa10, J. BAYONAa1a8a11, C. J. PACIOREKa12a13 and T. COHENa1a14 c1

a1 Division of Global Health Equity, Brigham and Women's Hospital, Boston, USA

a2 Department of Community Health, Mennonite Christian Hospital, Hualien, Taiwan

a3 Institute of Epidemiology and Preventive Medicine, National Taiwan University, Taiwan

a4 Division of Infectious Diseases, Brigham and Women's Hospital, Boston, USA

a5 Partners In Health, Boston, USA

a6 Decision Systems Group, Brigham and Women's Hospital, Boston, USA

a7 Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, USA

a8 Socios En Salud Sucursal Peru, Lima, Peru

a9 Instituto Nacional de Salud, Lima, Peru

a10 National TB Programme, Ministry of Health, Peru

a11 Department of Social Medicine, Harvard Medical School, Boston, USA

a12 Department of Biostatistics, Harvard School of Public Health, Boston, USA

a13 Department of Statistics, University of California, Berkeley, USA

a14 Department of Epidemiology, Harvard School of Public Health, Boston, USA.


We examined the spatiotemporal distribution of laboratory-confirmed multidrug-resistant tuberculosis (MDR TB) cases and that of other TB cases in Lima, Peru with the aim of identifying mechanisms responsible for the rise of MDR TB in an urban setting. All incident cases of TB in two districts of Lima, Peru during 2005–2007 were included. The spatiotemporal distributions of MDR cases and other TB cases were compared with Ripley's K statistic. Of 11 711 notified cases, 1187 received drug susceptibility testing and 376 were found to be MDR. Spatial aggregation of patients with confirmed MDR disease appeared similar to that of other patients in 2005 and 2006; however, in 2007, cases with confirmed MDR disease were found to be more tightly grouped. Subgroup analysis suggests the appearance of resistance may be driven by increased transmission. Interventions should aim to reduce the infectious duration for those with drug-resistant disease and improve infection control.

(Accepted November 19 2010)

(Online publication December 23 2010)


c1 Author for correspondence: T. Cohen, MD, DrPH, 641 Huntington Avenue, Boston, MA 02115, USA. (Email: tcohen@hsph.harvard.edu)