Eradicating poverty would dramatically reduce TB cases, study finds

Programmes to tackle poverty could be just as effective in the fight against tuberculosis as medicines and vaccines, research has found.

Eradicating extreme poverty would lead to an 84% reduction in TB cases by 2035, according to a report published to coincide with World Tuberculosis Day on Saturday.

Nine scientists and policymakers carried out research examining incidences of TB across 192 countries for a study that appears in Lancet Global Health.

The conclusions were reached by looking at the links between people living on less than $1.90 a day and the coverage of various social programmes in each country. Researchers then related this to the current levels of TB, projecting the associations forward 20 years.

More than 95% of deaths from TB occur in low- and middle-income countries, so the association between poverty and TB are well established. However, researchers say the latest findings are significant in providing new evidence of the links.

“This study is important to show that preventative measures have great impact,” explained Daniel Carter, research fellow at the London School of Hygiene and Tropical Medicine.

“We tend to only engage with TB patients when they are already ill, but this is not enough to eliminate TB. Poverty reduction could be just as effective in tackling the disease as drugs and vaccines.”

Carter, who co-authored the study, added: “Science is sexy but poverty elimination is not. If a biomedical tool were to show the same efficacy on TB it would be immediately implemented, but expanding social programmes requires more political will and ambition from health and development leaders.”

Tuberculosis is among the top 10 causes of death worldwide. In 2016, 10.4 million people fell ill with TB and a further 1.7 million died from the disease.

The bacterial infection mainly affects the lungs and can be spread through inhaling tiny droplets from the coughs or sneezes of an infected person. There is a vaccine for TB, but it has limited effectiveness.

The countries worse affected by the disease include India, China, Philippines, Pakistan, Nigeria and South Africa.

In its 2015 End TB Strategy, the World Health Organisation, for the first time, called for social support and poverty alleviation strategies for people with TB.

Now scientists say there is a growing body of evidence that social programmes are alleviating the burden in some regions.

A study in Brazil found a state-led cash transfer programme, conditional on eligible families sending children to school and giving them basic vaccinations, can improve treatment outcomes for TB by 10%.

“Social protection programmes, such as Brazil’s Bolsa Familia scheme, could potentially lift vulnerable individuals far enough out of poverty that they never contract TB in the first place,” said Carter.

The programme covers around 14 million families – amounting to 25% of the Brazilian population – who have a family per capita income of less than £30 a month. Cash assistance of £35 a month to each household has halved extreme poverty in the region.

Carter said the 10% improvement figure is significant because the programme is not specifically targeted at TB patients. If such a programme was extended to all those suffering from TB it would be incredibly cost-effective.

Carter acknowledges drugs and vaccines for TB play an important role, but added: “Eradicating TB will never be about DNA sequencing or shorter drug regimens. Biomedical innovation takes money and time – two things TB patients do not have.

“Anti-poverty policies are available now and the evidence suggests they work. The battle to end TB is not just against a pathogen, but an ideology.”

Tom Wingfield, clinical lecturer in infectious diseases at Liverpool University, agrees.

“Recent global TB control strategy has been disproportionately focused on medicines and tests rather than addressing the social causes of the TB epidemic.”

Wingfield has been gathering evidence of the links between poverty reduction and TB in shanty towns near Lima, Peru along with the research group, Innovation for Health and Development.

The team examined the hidden costs in TB-affected households including travel to clinics, food and lost income. When the costs exceeded a fifth of a household’s annual income the patient was more likely to abandon treatment or die.

“Our findings had identified a crucial factor explaining why medicines alone were not controlling TB. In response we provided social and financial support for affected households – bank transfers of up to $40 a month and visits by our research nurses,” he said.

“The intervention was a success. Supported TB patients were significantly more likely to complete their treatment or be cured, and their children were more likely to take medicine to prevent TB.”