One in every four people in the developing world die from tuberculosis - a disease that claims up to 4 million lives each year. These are some of the alarming statistics highlighted at the opening of a TB symposium in Yaoundé, Cameroon this week.
The World Health Organisation (WHO) estimates that between eight and 12 million new infections occur every year, a third of which occur in Africa. Up to 15%, or 450,000, are children on the continent.
South Africa has one of the highest incidence of tuberculosis in the world and is ranked fifth on the WHO's list of high burden countries. In 2007, 111,924 South Africans died of TB while 335,911 new infections occurred in the same year.
Africa is falling well behind global targets for the treatment and control of tuberculosis, Professor Christopher Kuaban from the University of Yaoundé said in his opening address for the TB symposium, hosted by the Novartis Institute for Tropical Diseases.
The reason for Africa's backlog, Kuaban explained, is that countries like South Africa, as well as well as other countries in sub-Saharan Africa, face a unique set of challenges in the fight against tuberculosis.
Conditions fuelling the spread
Poor, overcrowded living conditions, which are a common sight in South Africa, fuels the spread of the disease.
The high burden of HIV/Aids is a great obstacle in the fight against tuberculosis, especially so in South Africa where more than 5,7 million people are living with HIV.
Not only does HIV suppress a person’s immune system, significantly increasing their risk of acquiring TB, but co-infection with HIV and TB creates makes TB more difficult to detect and treat.
TB is also very labour-intensive to treat: it requires good laboratory facilities and skilled laboratory technicians to get an accurate diagnosis; and the treatment regime (DOT or Directly Observed Treatment) requires a DOT-trained person to be present every day for the duration of treatment (five to eight months) when each patient takes their medication.
This is to ensure adherence to the drug regime as failure to take medication, or taking it incorrectly, can lead to drug-resistance in patients and also cause relapse.
These challenges place a great burden on a health-care system like South Africa's, which is already weighed down by the country’s HIV/Aids pandemic.
Drug resistance a battle
Another great challenge in the fight against tuberculosis is drug-resistance. When a patient starts taking anti-TB medication, but don't take the it correctly, or stop treatment before the end of the treatment regime – something that happens regularly as patients stop taking medication once they start to feel better – the bacteria that causes TB is not eliminated from the body, but only suppressed by the drugs, then it becomes more virulent and develops resistance to two of the most powerful drugs used to treat the disease.
Once TB develops into the drug-resistant strain, the drug-resistant patient can infect others with this more virulent strain. These new infections don't go through the process of regular TB developing into drug-resistant TB, but a person can be directly infected with the drug-resistant strain.
Drug-resistant TB is more difficult to treat as the two most powerful drugs (Isoniazid and Rifampicin) are rendered ineffective and other, more expensive drugs have to be given over a much longer period of time (12 to 18 months) to treat it. Treatment for multi drug-resistant (MDR) TB is in the region of R25 000 for drugs alone, while hospitalisation of MDR patients could cost the Department of Health up to R100 000 per patient.
Of the 30,000 cases of drug-resistant TB diagnosed worldwide, 16,000 were in South Africa.
The week-long TB conference in Yaoundé brings together world-renowned TB experts, African scientists and medical tuberculosis experts to discus critical treatment and prevention issues in tuberculosis.
- (Wilma Stassen, Health24/October 2010)