Patients queue for anti-tuberculosis drugs at the Blue house clinic, run by medical charity Medecins Sans Frontieres (MSF), in the Mathare valley slums in Nairobi March 22, 2007. Living conditions in Africa's teeming slums have given rise to a multi-drug resistance strain of tuberculosis (MDR-TB) that kills nearly half of those who receive treatment, an aid agency said on Thursday. REUTERS/Damien Guerchois (KENYA) 

Monica Awino, 19, an orphan living with HIV/AIDS and tuberculosis, sits in her house in the Mathare valley slums in Nairobi March 22, 2007. Treating MDR-TB and HIV simultaneously is difficult as there are drug interactions and the potential for side effects is multiplied. Patients have to endure regular injections and take a large amount of pills on a daily basis. REUTERS/Damien Guerchois (KENYA) 

Monica Awino, 19, an orphan living with HIV/AIDS and tuberculosis, queues for drugs at a clinic in the Mathare valley slums in Nairobi March 22, 2007. Treating MDR-TB and HIV simultaneously is difficult as there are drug interactions and the potential for side effects is multiplied. Patients have to endure regular injections and take a large amount of pills on a daily basis. REUTERS/Damien Guerchois (KENYA) 

A doctor listens to a tuberculosis patient at the Blue house clinic, run by medical charity Medecins Sans Frontieres (MSF), in the Mathare valley slums in Nairobi, March 22, 2007. Living conditions in Africa's teeming slums have given rise to a multi-drug resistance strain of tuberculosis (MDR-TB) that kills nearly half of those who receive treatment, an aid agency said on Thursday. REUTERS/Damien Guerchois (KENYA) 

A child contaminated with tuberculosis and her mother wait for treatment at the Blue house clinic, run by medical charity Medecins Sans Frontieres (MSF), in the Mathare valley slums in Nairobi, March 22, 2007. Living conditions in Africa's teeming slums have given rise to a multi-drug resistance strain of tuberculosis (MDR-TB) that kills nearly half of those who receive treatment, an aid agency said on Thursday. REUTERS/Damien Guerchois (KENYA) 

Monica Awino, 19, an orphan living with HIV/AIDS and tuberculosis, walks home from a clinic in the Mathare valley slums in Nairobi March 22, 2007. Treating MDR-TB and HIV simultaneously is difficult as there are drug interactions and the potential for side effects is multiplied. Patients have to endure regular injections and take a large amount of pills on a daily basis. REUTERS/Damien Guerchois (KENYA) 

Monica Awino, 19, an orphan living with HIV/AIDS and tuberculosis, takes her medication inside her house in the Mathare valley slums in Nairobi March 22, 2007. Treating MDR-TB and HIV simultaneously is difficult as there are drug interactions and the potential for side effects is multiplied. Patients have to endure regular injections and take a large amount of pills on a daily basis. REUTERS/Damien Guerchois (KENYA) 

Monica Awino, 19, an orphan living with HIV/AIDS and tuberculosis, walks home from a clinic in the Mathare valley slums in Nairobi March 22, 2007. Treating MDR-TB and HIV simultaneously is difficult as there are drug interactions and the potential for side effects is multiplied. Patients have to endure regular injections and take a large amount of pills on a daily basis. REUTERS/Damien Guerchois (KENYA) 

A woman is treated for the multi-drug resistant tuberculosis (MDR-TB) at the Blue house clinic, run by medical charity Medecins Sans Frontieres (MSF), in the Mathare valley slums in Nairobi, March 22, 2007. Living conditions in Africa's teeming slums have given rise to MDR-TB that kills nearly half of those who receive treatment, an aid agency said on Thursday. REUTERS/Damien Guerchois (KENYA) 

Patients queue for anti-tuberculosis drugs at the Blue house clinic, run by medical charity Medecins Sans Frontieres (MSF), in the Mathare valley slums in Nairobi March 22, 2007. Living conditions in Africa's teeming slums have given rise to a multi-drug resistance strain of tuberculosis (MDR-TB) that kills nearly half of those who receive treatment, an aid agency said on Thursday. REUTERS/Damien Guerchois (KENYA)