Background There are high rates of active tuberculosis (TB) in London’s hard to reach groups (homeless people, substance misusers and prisoners). However no systematic data are available regarding the prevalence of latent TB infection (LTBI) and blood borne viruses (BBV) - HIV, Hepatitis B and C (HBV, HCV). Hard to reach groups often present late for healthcare. We undertook a TB/BBV screening programme to assess the prevalence of LTBI and co-infection with BBVs within homeless hostels, drug services and a prison in London. We also investigated management outcomes in those referred on to healthcare services.
Design/method Recruitment took place from May 2011–June 2013. Service users screened for TB on a mobile chest x-ray unit and in prison using the static digital x-ray machine were approached and, with consent, blood was drawn for IGRA (Quantiferon In-Tube) and HIV, HCV and HBV. Results were provided to participants with onward referral to healthcare services in line with current guidance. Treatment outcomes were collected via telephone follow up one year post referral for the positive cases.
Results Prison (n = 511) (Table 1)
LTBI: 65(13%) participants were IGRA positive [3(5%) co-infected with HCV]. Of these, 37(57%) were referred for preventive treatment, 16(43%) did not attend (DNA) appointments and were discharged or were lost to follow up (LFU). Of the 15 who commenced treatment, 9(60%) completed treatment.
HCV: 22 participants were positive and referred, of which 11(50%) DNA/LFU, 11(50%) were under review and none commenced treatment.
HBV: 10 participants were positive, of which 6(60%) DNA/LFU, 4(40%) were under review and none commenced treatment.
There were no HIV positives.
Community (N=696) (Table 1)
LTBI: 116(17%) participants were IGRA positive [22(19%) co-infected with HCV]. Of the 14(12%) referred to services, 8(57%) DNA/LFU and 3(21%) commenced treatment (2 completed).
HCV: 84 were positive and referred (8 new diagnosis), 42(50%) DNA/LFU/declined referral, and 37(44%) under review. Five (6%) commenced treatment, one completed.
HBV: 9 participants had current infection, none started treatment; 6 were under review and 3 DNA/LFU.
HIV: 9 participants were positive and known to healthcare services.
Conclusion The prevalence of LTBI, BBVs and co-infection within the hard to reach group is high compared to the general population with fewer patients starting TB prophylaxis/HCV treatment. The high overall rates of DNA/LFU (47%) seen indicate that current approaches to onward referral and retention in care for this group appear to be poor and effective measures to improve engagement with clinical services are essential.
This study was supported by NIHR Programme Grant for Applied Research (RP-PG-0407–10340).