Modest Gains Against TB, World’s most infectious Disease

Although it seems almost forgotten in the developed world, a full 25 percent of the world’s population, about 2 billion people, are infected by tuberculosis bacteria – although most don’t get sick – and 1.8 million will die each year, making the disease the world’s leading infectious killer according to the US Centers for Disease Control.

The global fight against TB, however, is making modest gains, although largely not yet on track to end the disease. The 2019 Global TB Report of the World Health Organization launched on October 17 gives hope, because sustained efforts have yielded some significant results. The European region is on track to meet 2020 targets of a 20 percent reduction in new cases with a 35 percent reduction compared to 2015. Seven high-burden countries are also on track to meet these 2020 targets: Kenya, Lesotho, Myanmar, Russia, South Africa, Tanzania, and Zimbabwe. The rest of the world is lagging behind.

The fight against the disease faces major impediments. The first is that millions now have a disease that is resistant to multiple drug treatments and the second is that many of those living with HIV are particularly prone to infection by tuberculosis, and a disheartening number of children are infected in less-developed countries.

An estimated 10 million people fell ill with the disease in 2018, with rates in children rising by 100,000 in 2018 to 1.1 million estimated in children in 2018 against 1 million in 2017 according to reporting in 202 countries and territories that account for more than 99 percent of the world’s population and estimated cases.

Drug resistance is a problem

In 2018, half a million cases were reported resistant to the potent antibiotic rifampicin, the main defender against not only tuberculosis but leprosy, Legionnaire’s disease and Mycobacterium avium complex, similar levels to 2017.

Of these, 78 percent were of multidrug-resistant TB, known by its initials MDR-TB in 2018, down slightly over 2017). India accounts for 27 percent of drug-resistant TB burden followed by 14 percent in China and 9 percent in Russia.

“But more alarming is that over 50 percent of previously treated cases of the former Soviet Union region had these drug-resistant forms of TB in 2018,” said Shobha Shukla, Executive Director of Citizen News Service, a grim reminder that a lot more needs to be done to eliminate drug resistance as only 1 in 3 multi-drug resistant patients were enrolled in treatment in 2018.

India is home to 43 percent of resistant patients but who are not yet being treated. Four key actions to bridge this gap include increases in detection, bacteriologically confirmed cases, coverage of drug-resistant TB testing and provision of treatment for drug-resistant TB.

About half of those resistant to multiple drug regiments were successfully treated in 2018. High MDR burden countries with better treatment success rates are Bangladesh, Ethiopia, Kazakhstan, and Myanmar.

Globally 51 percent of people who had bacteriologically confirmed TB were also tested for rifampicin resistance, up from 41 percent in 2017. This rifampicin resistance testing coverage was 46 percent in new and 83 percent in previously treated TB cases.

Added Burden of HIV

Some 64 percent of notified TB cases had a documented HIV test result in 2018 compared to 60 percent in 2017. TB-HIV coinfection is highest in Africa where 87 percent of notified TB cases had a documented HIV test result. Of an estimated 862,000 of TB co-infected people living with HIV, 56 percent (477,461) were detected to have TB. Out of those detected, 86 percent were on antiretroviral therapy in 2018.

WHO guidance issued in 2018 recommends TB preventive treatment for people living with HIV, household contacts of bacteriologically confirmed pulmonary TB cases and clinical risk groups (e.g. those receiving dialysis). The UN target of providing preventive treatment to 30 million people during 2018-2022, of which 6 million will be living with HIV, and 24 million will be household contacts (4 million children aged under 5 years, and 20 million other household contacts).

Globally in 2018, 65 countries reported initiating TB preventive treatment for 1.8 million people living with HIV, up from just under 1 million in 2017. South Africa accounted for 61 percent of the total number of people living with HIV enrolled in TB preventive treatment in 2018.

Of the 38 high TB or TB-HIV burden countries, 16 reported providing treatment to people newly enrolled in HIV care in 2018. Among these, coverage ranged from 10 percent newly enrolled in care in Indonesia to 97 percent in Russia. Overall, in 66 countries for which it could be calculated, coverage was 49 percent. In India, 17 percent of new cases of people living with HIV notified in 2018 (175,361) were put on TPT (29,214).

Children with TB

Globally in 2018, an estimated 1.3 million children aged under 5 years were household contacts of those bacteriologically confirmed to have pulmonary TB. The number of household contacts initiated on TB preventive treatment in 2018 was much smaller: data reported by 109 countries show 349,487 children aged under 5 years (a 20 percent increase from 292,182 in 2017), equivalent to 27 percent of the 1.3 million children estimated to be eligible; and 79,195 people in other age groups (a 30 percent decrease from 103,344 in 2017) received TPT. Among estimated number of eligible children under 5 years of age in India (322,000), 26 percent were put on TPT (83,109).

TB rates for healthcare workers

The ratio of the TB notification rate among healthcare workers to the TB notification rate in the general adult population is a good indicator of the impact of TB infection prevention and control in health facilities and should be around one. In 2018, 22,819 healthcare workers from 74 countries were reported with TB with India accounting for 56 percent of these cases and China for 16 percent.

In eight countries (Algeria, Burkina Faso, Colombia, Dominican Republic, Honduras, India, Lesotho and the United Republic of Tanzania), the number of TB cases per 100,000 healthcare workers was more than double the notification rate in the general adult population.

Bobby Ramakant is part of the Citizen News Service editorial. Follow him on Twitter @bobbyramakant or visit www.citizen-news.org