High rates of drug-resistant TB among prisoners

Prisoners in the UK are significantly more likely to have drug-resistant TB than other people with the disease, suggests research published in the Journal of Epidemiology and Community Health.
And one in four of TB cases fall through the healthcare net once they leave prison, researchers at the London-based Health Protection Agency Centre for Infections have found.

The team profiled the features of newly diagnosed adult cases reported to the national TB surveillance service for England and Wales between 2004 and 2007.
During this period, 29,340 cases of TB disease were reported, of which 205 were prison inmates.
An overseas birth is a known risk factor for TB. But prisoners with TB were almost twice as likely to be born in the UK rather than overseas — 47 per cent vs 25 per cent — compared with other TB patients.
And they were nine times more likely to be of black Caribbean ethnicity (18 per cent vs 2 per cent). Three out of four also had TB disease in their lungs, compared with just over half (56 per cent) of other TB patients, and those prisoners with TB in their lungs were significantly more likely to be infectious — 69 per cent vs 57 per cent.
Rates of drug-resistant disease were also extremely high among prisoners. More than one in three (35 per cent) had a strain of TB that was resistant to the drug normally prescribed as treatment — isoniazid. This means that a minimum 4 per cent of all drug resistant cases occurred in prisoners during this period, the researchers point out, and among drug-resistant cases born in the UK, 11 per cent were known to be prisoners (25 out of 228 cases).
Prisoners also fare worse than other TB patients, the study shows: fewer than half completed their treatment within a year (48 per cent vs 80 per cent). And one in four of those still receiving treatment when they left prison fell through the healthcare net and did not get further check-ups. More than half of them (55 per cent) had the drug-resistant form of TB.
Compared with other TB patients, fewer prisoners died before they completed their treatment, but their average age at death was significantly lower, at 48 compared with 70. The authors warn that their figures are likely to underestimate the true prevalence of TB disease among UK prisoners as the study did not include former prisoners or those with latent/unreported infection.
“High rates of [TB], especially drug-resistant tuberculosis, among prisoners with low levels of successful treatment mean prisoners present a particular challenge for tuberculosis control,” they stated.
J Epidemiol Community Health (2009). doi:10.1136/jech.2009.094375.