Enhanced tuberculosis (TB) surveillance was introduced in Scotland in 2000 through the Enhanced Surveillance of Mycobacterial Infections (ESMI) scheme. In 2018, a total of 271 cases of TB were reported to the ESMI scheme, equating to an annual incidence of 5.0 cases per 100,000 of the population. This was a 7.5% decrease in case numbers and a 7.7% decrease in annual incidence when compared with 2017 (293 cases, 5.4 cases per 100,000 of the population). This represents the eighth consecutive annual decrease in TB case numbers and incidence since 2010, with TB case numbers and incidence now both at their lowest levels since ESMI began.
Drug resistance was noted to have increased in 2018, with the proportion of isolates with resistance to at least one first line drug (15.8%) and to isoniazid (8.7%) and pyrazinamide (8.7%) individually all at the highest levels seen since enhanced surveillance began. There were two cases of multidrug-resistant TB and no cases of extensively drug-resistant TB in 2018. This is a concerning finding, as drug-resistant TB is more difficult and expensive to treat and, as a result, patients can remain infectious for longer.
Treatment outcomes at 12 months were recorded for 94.5% of cases initially reported in 2017, of whom 85.8% successfully completed treatment. This is the highest treatment completion rate reported since outcome reporting began in 2001. The number of TB cases with death recorded as an outcome at 12 months decreased from 34 cases in 2016 to 19 in 2017.
The full report, published on 29 October 2019, can be viewed on the Health Protection Scotland (HPS) website.