Medical workers are increasingly concerned that the lethal combination of HIV infection and tuberculosis may become the world's next major health crisis.
To mark World TB Day on Wednesday, Medecins Sans Frontieres drew attention to Lesotho, which has the world's third-highest prevalence of HIV, the virus that causes AIDS, and the fourth-highest prevalence of tuberculosis. Here, poverty and violence complicate treatment in a country where life expectancy is a mere 36 years.
Michel Sidibe, head of the UN AIDS program, fears the double infection could become the next new epidemic.
"I'm calling for serious attention to TB, and serious attention to TB-HIV co-infection," he said in an interview.
In this mountainous kingdom surrounded by South Africa, some patients battling HIV and tuberculosis must walk five hours to reach a clinic for their medication.
"It is a problem for us to come to the clinic because sometimes there are gangster men waiting down by the side of the river ... and yes, sometimes women are raped," said Tlalane Tsiane, a 21-year-old woman infected with TB and HIV.
Many men in Lesotho travel to South Africa to work in the mines and some return with HIV and a form of tuberculosis that is resistant to multiple antibiotics. The World Health Organization believes drug-resistant strains present a major challenge to the global effort to control the disease.
Helen Bygrave, a medical coordinator for Medecins Sans Frontieres, also known as Doctors Without Borders, estimated that between 80 to 90 percent of Lesotho's TB patients are infected with HIV.
A person whose immune system is compromised by HIV is particularly susceptible to tuberculosis, which is caused by bacteria that usually attack the lungs. The disease is spread through the air when an infected person coughs or sneezes.
There are nearly 9 million new cases of TB worldwide and the disease kills more than 1.5 million people every year, according to the World Health Organization, even though it can be cured with a six-month course of antibiotics that costs only $20.
Sera Thoola, a retired miner of 47, believes that he contracted TB in South Africa. It is also where he first tested positive for HIV. He has multi-drug-resistant TB, and is currently taking an average of 49 pills a day to control his diseases.
Most clinics in Lesotho were set up through partnerships between the government and international groups. In seeking ways to make the most of scarce resources, Medecins Sans Frontieres is helping to support and run a program in which nurses are given training to take on roles doctors might have carried out. Community health workers later make sure patients are sticking to their treatment regime.