South Africa Perspective: Tuberculosis
Tuberculosis is a serious public health issue in South Africa. About 450,000 people develop the disease every year, and 270,000 of those are also living with HIV. TB is South Africa’s leading cause of death. About 89,000 people die from it every year; that’s ten people every hour. Effective treatments are available and the country has made considerable progress in fighting the disease, but much more is needed to bring it under control.
The post-2015 agenda being finalised by the international community introduces some ambitious targets to end the global epidemic, and the current South African government has gone beyond these. The government is now committed to screening 90% of those at risk of contracting TB, ensuring that 90% of suspected cases are correctly diagnosed and treated and ensuring that 90% of those treated are cured.
Many people carry a latent infection, with only 5% going on to develop active TB within eighteen months and the same percentage at risk of developing TB later in life. Most cases are drug-sensitive and respond well to standard treatment with a combination of drugs, but failure to complete a proper course of treatment encourages the development of multi-drug resistant TB (MDR-TB), which is difficult and costly to treat and has poorer outcomes. Around 1.8% of new cases of TB in South Africa are multi-drug resistant.
HIV infection is a key factor in the TB epidemic. HIV sufferers have a higher risk of contracting TB and a greater chance of dying. In 2013, almost one million HIV-positive people were screened for TB, but more needs to be done to reach more of the over six million living with HIV. Preventive treatment for those with latent TB is relatively low-cost and can be delivered with HIV treatment (anti-retroviral drugs). But, despite several million people being eligible, only 340,000 were receiving this treatment according to 2014 figures.
Diagnosis is quite complex (particularly for those living with HIV), since many symptoms are similar to those for other common diseases. South Africa has moved towards more intensive and active methods of identifying cases, for example by screening all those attending primary health clinics. The aim is to move from identifying fewer than 70% to 90% of all cases.
Diagnosis using a microscope to screen sputum samples is cheap and the most common method used. However, it may miss substantial numbers of sufferers and more expensive techniques are needed to improved detection rates, particularly of those living with HIV, and find cases of drug-resistant infection. South Africa was one of the first countries to roll out the WHO-recommended Xpert MTB/RIF assay.
But screening is not the only factor. Ways must be found to ensure that patients return for results and also complete their treatment. Over 90% of people can be cured, but the rate is only 77% in South Africa. Treatment of MDR-TB is much more complex and costly (with possibly over half the South African budget for TB going on this). The success rate, at 45%, is also lower than for many other countries.
Poverty contributes to the problem by making people less likely to seek care and finish treatment, and poor nutrition can also reduce the chances of being cured. The average cost of a complete episode of TB can be almost 4,000 Rand, including loss of earnings, which is a major burden for poor families.
Currently, it costs about 2,500 Rand to treat a straightforward case of TB, rising to about 115,000 for treating MDR-TB. Reaching the target of reducing deaths by 90% would cost about 5 billion Rand per year in additional spending. Making this investment between 2016 and 2035 would give a total of 450,000 additional years of life to South Africans.
Valuing a year of life at $5,000 (60,000 Rand) means that each Rand invested would be worth around 5 Rand in benefits (extra years of life). This is probably an under-estimate for a country like South Africa, and does not take account of indirect economic benefits. In any case, tackling the TB epidemic would be a sound economic investment.