Union review paper highlights critical action points for the treatment of TB infection

A review paper titled Treatment for latent tuberculosis infection in low- and middle-income countries: progress and challenges with implementation and scale-up, has been published on-line in the journal Expert Review of Respiratory Medicine. The review, written predominantly by Union consultants and members of the Centre for Operational Research addresses the need for a rapid scale-up of treatment for tuberculosis infection (TBI), also known as latent TB infection (LTBI), considering who should be targeted, and the best means of treating them.

The global burden of TBI is currently estimated to be at 23 percent or approximately 1.7 billion people, with between five and 10 percent of those with TBI developing active TB. Despite the prevalence, the treatment of TBI is a neglected component of global TB control. It has now been recognised that to achieve targets to end the epidemic of TB, essential actions are required in preventive treatment of persons at high risk of TB. As a result, last year’s United Nations (UN) High-Level Meeting (HLM) on the fight against TB committed world leaders to provide TBI treatment to at least 30 million people.

To address key issues in the treatment of TBI, the review searched the literature, using the MEDLINE database, between 1990 and 2019, and raised the following key points:

  • Basic research is needed to identify a better diagnostic test that is sensitive, specific, affordable, easy to implement, and can predict who is truly infected with TBI and will progress to active disease.
  • For the treatment of TBI, HIV programmes must focus on people living with HIV, who are about to start, or are already accessing, antiretroviral treatment (ART). TB programmes must focus on household contacts of patients with bacteriologically confirmed TB - more specifically those under five years worldwide, and all other household contacts in countries with a high-TB burden. These groups do not require testing for TBI before implementing treatment.
  • Taking isoniazid for six months is the main treatment of choice, but longer or continuous therapies should be considered for people living with HIV in high TB-burden countries. A three-month course of weekly rifapentine and isoniazid or a one-month course of daily rifapentine and isoniazid would be suitable alternatives if the costs of rifapentine can be brought down. Programmes should work out how to avoid and quickly identify isoniazid-induced hepatitis, which can be fatal – such an occurrence can derail a TB preventive therapy programme.
  • Better recording and reporting of TBI treatment is urgently needed. WHO needs to produce and disseminate advice about how this will be achieved, bearing in mind that reporting should be kept as simple as possible, hence not overburdening healthcare staff.

In 2017, the treatment of TBI was given to less than 1.5 million eligible persons according to global reports. In the five years from 2018 to 2022, this must increase to an average of at least six million persons per year to achieve targets.

Professor Anthony Harries, lead author and Senior Advisor for Research at The Union, said: “HIV/AIDS programmes need to step up to the plate regarding combining ART with TB preventive therapy to drive down TB incidence amongst people living with HIV. Equally, TB programmes must do the same, focussing on household contacts of index TB patients. We are woefully short of the targets set by the UNHLM for treating people with TBI and we must have immediate concerted action to address this failing.”

Treatment of TBI is one component of a larger TB prevention effort. Recently at the 50th Union World Conference on Lung Health, The Union launched an open access and online training programme: Prevent Tuberculosis: Management of TB Infection.