Integrated care critical to saving lives from TB-HIV co-infection
Tuberculosis (TB) and Human Immunodeficiency Virus (HIV) pose a serious health risk. According to the World Health Organisation (WHO), the risk of developing TB is estimated to be between 26 and 31 times greater in people living with HIV (PLHIV). In 2015, there were an estimated 10.4 million new TB cases worldwide, of which PHLIV accounted for 1.2 million (11%) cases. TB caused 400,000 deaths among the PLHIV of the 1.4 million who died of TB in the same year. The TB-HIV co-infection is potentially lethal combination.
When a person develops HIV, his/her immune system loses its ability to fight off infections, making him or her more vulnerable to other infections like TB. People living with HIV are especially vulnerable to tuberculosis in countries where TB is common. Roughly, 75% of PLHIV who contract TB live in sub-Saharan Africa. In some countries in this region, up to 80% of individuals with active TB disease are also HIV-positive.
TB-HIV increasingly poses a risk to people living in other regions. Roughly 30% of all people who become sick with tuberculosis live in Asia, where TB accounts for 40% of AIDS deaths. Eastern Europe has the fastest-growing HIV epidemic globally, making this region vulnerable to increasing TB-HIV co-infection as well, according to the WHO.
According to Dr Anthony D. Harries, Senior Advisor and Director, Department of Research, International Union Against Tuberculosis and Lung Disease (The Union), a healthy person has a 5-15% life time risk of contracting TB whereas a person with HIV has an annual 5-15% risk of contracting TB.
""Antiretroviral Therapy (ART) suppresses HIV replication and this leads to a gradual increase in CD4 cell counts. These increased CD4 cell counts protect against TB. Studies have shown that CD4 count of less than 100 can have a TB rate of 25.5 per 100 per year as against a CD4 count of more than 700 where this rate falls to 2.7. In the case of an individual who is not infected with HIV, the rate is less than 0.62 per 100 per year,ââ Dr Harries explains.
Isoniazid Preventive Therapy (IPT) also reduces the overall risk of TB by 33% in PLHIV, Dr Harries says while adding that synergizing IPT to ART would greatly benefit the patients as studies had shown a 37% reduction in TB among people living with HIV as compared to ART alone.
According to WHO, measures have been taken to integrate TB-HIV care in countries around the world, with increasing success. For example in 2014, 77% of people living with HIV who were also diagnosed with active TB, were placed on anti retroviral treatment (ART). Still, opportunities are being missed as only 47% people on ART were screened for TB, only 51% people diagnosed with TB were tested for HIV, and only half of the estimated number of people living with HIV who developed TB were diagnosed and provided with TB care.
The Union has committed to addressing this lethal co-epidemic through an integrated care approach known as Integrated HIV Care for Tuberculosis Patients Living with HIV/AIDS (IHC). This approach aims to strengthen collaboration and build capacity of affected countries' general health systems to deliver high-quality HIV and TB care.
Between 2000-2014, WHO estimates that 8.4 million lives have been saved through integrated and collaborative TB-HIV activities. There are still many more lives to save and more needs to be done to achieve universal access and to eliminate HIV-associated TB deaths. To begin, WHO recommends that all patients with presumptive or diagnosed TB should be tested for HIV.
According to WHO, the funding required for a full response to the global TB epidemic in low- and middle-income countries was estimated at US$ 8 billion per year in 2015, excluding research and development. As much as US$ 6 Billion could be mobilized from domestic sources, leaving a balance of US$ 2 billion needed from international donors. This gap fuels not only the spread of TB but also has serious implications for the health and safety of those living with HIV. Ending TB is crucial to the survival of those with HIV.
People living with HIV also face the threat of drug-resistant TB. If diagnosis is delayed, people living with HIV are at high risk of death from multidrug-resistant and extensively drug-resistant TB (MDR & XDR-TB).Integrated care is very important for patients at risk of co-infection with drug-resistant TB and HIV.
People living with HIV are also more likely than people who are not infected with HIV to have extra pulmonary TB. Between 40-80% of HIV infected people with TB have extra pulmonary disease, compared with 10-20% of people without HIV."