Promising early signs from mobile X-ray TB screening pilots
One of the most intriguing findings from South Africa’s first National Tuberculosis Prevalence Survey was that out of 234 people found to have TB, 58% had abnormal chest X-rays without experiencing any TB symptoms. Not surprisingly, the short report in which the findings were made public recommended the expanded use of X-ray technology for TB screening, something the World Health Organization (WHO) has also recently recommended.
In South Africa the first step in TB diagnosis is to ask people whether they have TB symptoms such as persistent cough, weight loss, night sweats, and fever. In general, only people who report TB symptoms go on to be tested for TB using molecular tests.
However, the expanded use of X-ray technology can change this. X-rays can, for example, be offered to people who do not have symptoms but who live in areas with high TB rates. If the X-ray is suggestive of TB, it can then be followed up with a molecular test to confirm the diagnosis. The hope is that this approach will help find more people with TB more quickly.
Last year, Spotlight reported on the launch of pilot projects in six districts in which such mobile X-ray screening strategies are being tried out. The pilots are coordinated by the National Department of Health in partnership with large donors such as the Global Fund to Fight AIDS, Tuberculosis and Malaria and the United States Agency for International Development (USAID). These donors have contracted several non-profit organisations to run the pilots in the six districts.
According to Yolisa Tsibolane, Director of Global Fund programmes at the National Department of Health, the use of Digital Chest X-Rays (DCXR) in mobile vans or containers remains in the pilot phase. She says an evaluation of the pilot project is currently underway and it is expected to be completed by May this year.
“The results of the evaluation will be used to inform the plans to scale up the use of DCXR in other provinces,” Tsibolane says. “Depending on the outcomes of the evaluation, the national and provincial departments will have to submit funding requests to the National Treasury for the required resources for the scale-up. Based on this, there are no set timeframes for the scale-up plan to other provinces.”
Where are mobile X-ray vans currently deployed
Alison Best, communications manager at TB HIV Care, says decisions around the placement of DCXR containers and mobile vans are made in consultation with Department of Health substructures. TB HIV Care is a non-profit that, among others, runs mobile X-ray projects in the Western Cape and KwaZulu-Natal.
“It is based on the mapping of ‘hot spots’ in high-burden areas using Geographic Information System (GIS) Technology. This technology uses case data and other independent variable datasets to identify and predict emerging hotspots. The GIS TB Hotspot Maps are generated by the GIS officer and provided routinely to the DCXR Mobile Team before screening events to guide them in selection of screening sites,” she says.
Tsibolane says the DCXR movable containers and vans for the Global Fund are staffed with a radiographer, nurse, data capturer, and a driver for the mobile vans.
“All staff are trained on how to operate the equipment before the use of DCXR, including capturing and reporting data,” she says.
Since the start of the pilot project in November 2020, Tsibolane says a total of 89 214 clients visited the 15 DCXR containers in the six districts – OR Tambo in the Eastern Cape, Ehlanzeni in Mpumalanga, Ekurhuleni and Johannesburg in Gauteng, Cape Town in the Western Cape, and eThekwini in KwaZulu-Natal.
According to Tsibolane, of the just over 89 000 clients who visited DCXR units, 95% (83 658) were X-rayed, 73% (61 220) had normal DCXR results, 9% (7 516) were abnormal TB suggestive, 18% (14 922) were abnormal, not suggestive of TB.
Sputum samples were also collected in cases where TB was suspected. “There were 15 466 sputum [samples] collected and tested,” she says. “10% (1 471) were TB positive, 1 359 clients who had DCXR and referred to the medical practitioner were started on treatment after a clinical diagnosis.”
She says a total of 2 712 clients who had DCXR were started on TB treatment – representing a yield of 3% and a TB treatment initiation rate of 92%. (The yield of 3% means that for every 100 people who were X-rayed, three people were eventually diagnosed with TB and started on treatment.)
Below we provide more detail on the X-ray pilot projects in the Western Cape, Eastern Cape, KwaZulu-Natal and Gauteng.
“Of everyone screened in the Western Cape, 2.2% were found to have TB, but about 30% of those clients were asymptomatic, meaning they are unlikely to have been diagnosed without the DCXR as further testing is usually based on symptom identification,” Best says.
She says in the Western Cape there are 11 DCXR units. Seven are modified shipping containers, meaning they can be moved, but require a truck to do so. The other four are modified vans.
In the Global Fund districts in the province (City of Cape Town), there are three movable X-ray containers and one mobile X-ray van. There is no plan to purchase another one for the Western Cape in the new financial year, according to Tsibolane.
The non-profit, Think TB, is supporting X-ray screening projects in four districts in KZN, including uMgungundlovu, uMkhanyakude, uThukela, and Amajuba.
“There are three mobile X-ray vans. One each for Umgungundlovu and uMkhanyakude and one shared by Amajuba and uThukela. The three vans were procured at a time when the project supported three districts, including eThekwini. The Department of Health then directed Think TB to move out of eThekwini and support the two districts [Amajuba and uThukela],” says Dr Panganani Dhliwayo, TB technical lead at Think TB.
As in other provinces, the vans will be used in high TB burden areas, commonly referred to as TB hotspots. “The vans will be stationed at high-burden facilities and will also be utilised in communities deemed hotspots. We propose one van per district should funding be availed to expand to other districts,” says Dhliwayo.
He says the TB technical lead in consultation with the Department of Health decide on the deployment of the vehicle based on the high TB volume areas and facilities.
“The van is also deployed based on the public health activities being carried out in the district. For instance, deploying it when celebrating World TB or World HIV days or any special community days,” he says.
“As part of testing the feasibility and usefulness of the vans,” he says. “We estimated that each vehicle will perform 50 X-rays a day, which translates to 250 a week and 1 000 a month. The three vans are expected to perform 36 000 X-rays in 12 months.”
According to Best, of everyone screened by TB HIV Care in KwaZulu-Natal, 8.8% were found to have TB, but about 16% of those clients were asymptomatic and were likely only detected because the DCXR was used.
In the build-up to World TB Day on 24 March, the Eastern Cape Department of Health received two mobile digital chest X-ray units from USAID through its funded non-governmental organisation, MatCH.
In a statement, MEC for Health Nomakhosazana Meth, said the mobile digital chest X-ray services will help in the department‘s quest to increase TB case findings. The vehicles will service various clinics within the Nelson Mandela and Sarah Baartman districts on a daily basis.
“The mobile X-ray units would ensure that the department takes TB screening and services directly to people,” Meth said.
So far, 1 132 patients (701 in OR Tambo and 431 in Buffalo City Municipality) were screened for TB using DCXR.
Meth said these two mobile X-ray units will assist them to ensure that they get to as many people as possible, particularly those in rural areas and townships who might not know they have TB.
“We want more people to get tested for TB and take treatment for the required months which may be six to 12 months or more so that they can beat TB,” she said in the statement. “We are grateful to our social partners because we would not have been able to deliver some services because of the serious budgetary constraints we have.”
Through The Global Fund, the Amathole District will get two mobile vans in the new financial year. Buffalo City has one mobile van and another will be added in the new financial year. The OR Tambo District has three movable containers and one mobile van.
Kwara Kekana, Gauteng’s Health spokesperson says there is one mobile X-ray van that operates in the West Rand Health District, but the single van is not enough.
“The West Rand Health District has only one mobile truck for the whole district, which is not limited to chest X-rays but all X-rays,” she says, adding that the district was not part of the pilot.
“However, distributing the project to all institutions will be good as there is a high rate of unemployed patients who cannot afford to go to the hospitals for X-ray services,” she says.
Kekana says that the mobile X-ray truck in the West Rand Health District moves daily from clinic to clinic and the rotation schedule is sent to facilities monthly. “Staff training is needed because the mobile truck is not the same as a fixed X-ray room,” she says, adding that overtime is currently being used because of staff shortages.
With the help of the Global Fund, Ekurhuleni has two containers while Johannesburg has three movable containers. The two districts share one mobile van.
From November to end-March this year, Kekana says 234 patients have made use of the mobile X-ray facilities.
Lessons learnt from pilots
Dhliwayo says in KwaZulu-Natal the community has warmed up to the intervention and demand for the service outstrips supply. “We have also learnt that the intervention yields high numbers of TB cases, which could not have been diagnosed otherwise,” he says.
According to Tsibolane, one major limitation with the use of containers was that they could not be moved easily to communities for targeted screening among high-risk populations. “This resulted in the procurement of seven mobile vans to reach community-based clients with DCXR screening,” she says.
Best says there are three critical elements needed for a successful screening campaign with the mobile digital chest X-ray van.
“There is need for collaborating closely with the local facility managers, HAST managers, and [the] Department of Health [and] engaging community leaders prior to the screening to ensure communities are mobilised when the mobile arrives in the area,” says Best. They also keep the truck in one area for at least three consecutive days to ensure that the service is accessible to everyone in the area.