Dr. O'Donnell's research interests center around global health including tuberculosis (TB), HIV, and severe acute respiratory infections. Current research is centered in South Africa and Uganda with training/education and capacity building work in Ethiopia. Important collaborators include the Centre for AIDS Programme of Research in South Africa (CAPRISA), KwaZulu-Natal Research Institute on TB/HIV (K-RITH), the Jacobs' and Larsen labs at Albert Einstein College of Medicine, and the Uganda Virus Research Institute (UVRI). Drug-resistant tuberculosis is an important global public health concern because of increasing incidence, low cure rates, and high reported mortality. Nowhere has this increased incidence generated more concern than in South Africa where interactions between TB and generalized HIV/AIDS epidemics are causing explosive increases in TB incidence and TB case-fatality rates. The most drug-resistant form of tuberculosis, extensively drug resistant tuberculosis (XDR-TB), is increasingly prevalent in South Africa. Acute respiratory infections continue to be responsible for approximately 3.9 million deaths worldwide, predominantly in children, without a substantial decrease in estimated mortality over the past 2 decades. In addition, outbreaks of emergent viral respiratory infections with pandemic potential and periodic outbreaks of severe acute respiratory infection caused by vaccine-preventable pathogens continue to threaten global health security.