This National Institute for Health Research (NIHR) programme grant was initiated because of the extreme challenges of controlling tuberculosis in socially complex groups that have great difficulty in accessing and using mainstream NHS tuberculosis services. The programme was ambitious and was working in highly challenging and complex settings. As researchers, we needed to adapt our methodologies in response to these challenges and we made these changes in discussion with the funders.
This study demonstrates that there are extremely high levels of latent tuberculosis infection and blood-borne viruses in people experiencing homelessness, prisoners and drug users; it also demonstrates the challenges of implementing screening programmes and ensuring that cases of infection are treated. It also shows that there are low levels of hepatitis B vaccination uptake in these groups. We show that, even at relatively low levels of treatment uptake, screening for latent tuberculosis infection in homeless groups is likely to be cost-effective at a willingness-to-pay threshold of £20,000–£30,000. This cost-effectiveness is likely to be improved by integrating with screening for blood-borne viruses and vaccination. Screening for latent tuberculosis infection and blood-borne viruses is now offered to patients experiencing homelessness screened by the mobile radiographic unit, along with vaccination for hepatitis B, influenza and Streptococcus pneumoniae.
Despite the NHS receiving ring-fenced funding to establish radiographic screening for tuberculosis in prisons and installing equipment in key prisons, none of the prisons had initiated and maintained routine radiographic screening. We provided a radiologist to support the pilot NHS programme and showed that screening was feasible and identified cases. Previous economic analyses have suggested that, if implemented, such screening would be cost-effective.
We have demonstrated that peer educators are no more or less effective than health-care workers in encouraging the uptake of mobile radiographic screening. We consider that the study findings may have been contaminated because the service already used peer educators to support its work. We consider that there are wider benefits of including peer educators as part of the Find&Treat team so that they can continue to work alongside health-care workers to encourage people to be screened and to support those identified with concerning radiographs to engage in further follow-up.
We overcame substantial technical difficulties to establish a polymerase chain reaction facility on the mobile radiographic unit. Although we were unable to fully evaluate this, the service has now been reinstated on the mobile radiographic unit and is used in situations where a strong need is identified, such as in response to tuberculosis outbreaks.
The most important component of our work is our trial of smartphone-enabled video-observed treatment (VOT). To our knowledge this is the first randomised controlled trial (RCT) evidence of this intervention to be published. We have demonstrated that the intervention can achieve high levels of adherence to daily treatment regimes in socially complex groups and is far superior to face-to-face, directly observed treatment (DOT) in ensuring treatment observation. The intervention is also cheaper than DOT. The technology has great potential to improve tuberculosis control internationally, particularly in preventing the development of drug-resistant tuberculosis and managing socially complex patients and those with multidrug-resistant tuberculosis. The London Find&Treat service has been commissioned to provide an NHS VOT service based on the model developed through this research. As part of this, the service provides support to the majority of London multidrug-resistant tuberculosis (MDRTB) cases. The service also provides VOT for selected cases nationally. Long-term funding arrangements for the VOT service, however, remain uncertain. VOT is now recommended in the World Health Organization (WHO) treatment guidelines1 and is being increasingly used internationally.
Although focused on tuberculosis, this research programme has implications for control of other infections and non-communicable diseases in socially complex groups. The emphasis on outreaching active case finding for tuberculosis and providing support for engagement in treatment is relevant across the spectrum of health conditions experienced by these groups.