One of South Africa’s foremost tuberculosis (TB) researchers, Dr Francesca Conradie, a principal investigator at the Clinical HIV Research Unit (CHRU), has called for a renewed focus on TB testing in South Africa to help find new TB cases that ‘went missing’ during the Covid-19 lockdown. TB testing, the mainstay of SA’s TB programme, took a severe knock during lockdown which has left many South Africans with undiagnosed TB. “We need to find them,” she says.
Conradie explains, “South Africa has a robust TB testing programme. Every year, we know how many tests we need to conduct to find TB cases. There were 207,000 laboratory-confirmed TB cases in SA in 2019. It is too early to tell how far below this figure we are for 2020. For HIV-positive people, the risk of developing TB is far greater. Among people with latent TB infection, HIV infection is the main risk for progressing to TB disease.
“As part of World Aids Day, the Clinical HIV Research Unit has called on healthcare workers to test patients with TB symptoms, especially HIV positive patients. People with symptoms should also ask for a TB test. TB spreads very easily because it is airborne. If left untreated, it is life-threatening. Delays in treatment can have a devastating impact on a person’s health while spreading it to others,” she says.
The symptoms of TB are coughing, chest pain, loss of weight, loss of appetite, coughing up blood, sweating at night, tiredness, weakness, shortness of breath and difficulty in breathing.
Says Conradie, “Until March this year, SA’s TB testing programme was going well. Then there was a significant drop in the number of people testing for TB when Covid overwhelmed the health system. People were scared to go to facilities. The consequence is that only sick people presented at with severe TB disease. We will be able to quantify this in about six months. TB is a long, insidious illness which is why we need to catch people with ‘a touch of TB’ early. If we do, patients have minimal lung disease and a far better prognosis.”
According to Dr Harry Moultrie, senior medical epidemiologist at the National Institute for Communicable Diseases’ Centre for Tuberculosis, “TB testing dropped by as much as 32% between March and October this year.”
Conradie also predicts that SA may see an increase in childhood TB as a result of the lockdown. “Families were confined to their homes for several weeks. One adult with undiagnosed or untreated TB would have infected children at home.”
SA’s TB testing programme returning to normal
“TB testing is resuming, but we need to catch up to find cases that were missed,” says Conradie. “Doctors in the field are saying that the number of TB cases is increasing to where it should be for South Africa to know it is dealing effectively with the disease, but the data to support this must still come through.”
Moultrie explains, “While there has been substantial recovery in both TB test volumes and detected cases in September and October, both test volumes and detected cases remained slightly below the lower forecast bound for the month of October.
“It is estimated that between the beginning of March and the end of October this year, 501,000 (uncertainty range: 406,000 – 597,000) fewer TB tests were conducted and 27,500 (uncertainty range: 20,500 – 35,000) fewer positive samples were detected as a result of Covid-19.
“The forecast values for tests and cases for each month have considerable uncertainty as they are forecast from historical data trends. The counterfactual – how many tests would have been conducted had there not been Covid – is unknown. The ranges incorporate this uncertainty in the projections.”
The World Health Organization lists South Africa as a priority country given its high infection rates for TB, TB/HIV and drug-resistant TB.