03/25/2013 02:55 pm ET Updated May 25, 2013

HIV and TB: Untangling a Deadly Knot

The tiny country of Swaziland, home to nearly 1.4 million, is facing not one, but two, epidemics. As I write from Swaziland's capital, Mbabane, the country is struggling to overcome twin epidemics of HIV and tuberculosis (TB). An estimated 190,000 people -- more than a quarter of Swaziland's adult population -- are living with HIV. At the same time, 16,000 Swazis develop life-threatening, active TB disease every year, while untold others are living with the silent and less dangerous, latent form of TB.

TB and HIV, each a major health problem on its own, intertwine to form a tight, deadly knot. HIV infection fuels the conversion of latent TB infection -- which has no symptoms and is not transmissible -- to active, airborne, contagious and potentially lethal TB disease. At the same time, TB bacteria accelerate the progression of HIV infection to AIDS, weakening the body's immune system until it can no longer fight disease. Every new HIV infection and every new TB case pulls this knot tighter, putting more lives at risk.

Here in Swaziland, more than three-quarters of TB patients are also living with HIV, and TB is the leading cause of death among people with HIV. While Swaziland is an extreme case, what is happening here is happening around the world: Globally, 430,000 people with HIV die of TB each year.

We have the knowledge and tools to end this vicious cycle. It requires integrating HIV and TB services as tightly as the epidemics themselves are tied together.

Integration means that HIV and TB services are no longer siloed. Everyone receiving care in TB clinics should also be tested for HIV.

In the growing number of HIV testing and treatment clinics, regular TB screening and prevention should be considered standard care. This includes isoniazid preventive therapy, which can reduce the likelihood that a person living with HIV will develop active TB disease by as much as two-thirds. It also includes effective infection control measures to prevent people with active TB passing on the airborne infection to people living with HIV but not already infected with TB.

Antiretroviral therapy has been found to reduce the risk of active TB by 65 percent. This is why people need to access HIV testing and treatment as early as possible to prevent TB.

These are clear, straightforward, and utterly achievable steps. And we are making important progress. Since 2005, collaboration between HIV and TB programmes has saved more than 1.3 million lives in developing countries.

This is because we are doing better at integrating HIV and TB services, including building HIV testing into TB care and ensuring that people get earlier treatment for HIV. Globally, the proportion of TB patients tested for HIV has increased substantially in recent years, with four in 10 patients now receiving testing. Countries with the highest burden of HIV and TB have the highest rates of testing, with sub-Saharan Africa leading the way.

We are also doing better at incorporating TB services into HIV care. More people enrolled in HIV care are being screened for TB, and the number of people provided with isoniazid preventive therapy more than doubled between 2010 and 2011. In 2011, nearly half of all people living with TB and HIV received antiretroviral treatment for HIV.

Yet halfway there is not nearly far enough. UNAIDS is working closely with partners including the Stop TB Partnership and the Global Fund to Fight AIDS, Tuberculosis and Malaria in Swaziland and other hard-hit countries to ensure that everyone living with both HIV and active TB is able to start HIV treatment, that everyone in TB care is offered an HIV test, and that everyone in HIV care is offered screening for TB.

We also need to expand screening for both HIV and TB to hard-to-reach populations, including sex workers, transgender people, people who use drugs, and men who have sex with men to ensure that everyone is aware of their status and able to begin treatment as early as possible.

It is time to commit the resources and energies needed to go the distance. It will take all of us -- governments, donors, civil society, affected communities, and businesses -- to achieve this goal. We must act now to stop people living with HIV from dying of TB.

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