Tuberculosis in Hong Kong has dropped to its lowest level since 1947, with 40 fewer cases reported last year than the year before, but the health authority urged the public to stay vigilant due to the city’s risk factors and ageing population. On Saturday, World Tuberculosis Day, the Hospital Authority and Tuberculosis Chest and Heart Diseases Association jointly sought to raise awareness of the contagious and airborne disease, which killed 1.7 million people worldwide in 2016 according to the World Health Organisation (WHO). Between 2000 and 2016, tuberculosis was one of the top 10 causes of death globally despite the mortality rate falling by 37 per cent during that period, according to the WHO. Girl infected with drug-resistant tuberculosis held in quarantine at Hong Kong hospital Statistics from the Health Department showed that in 2017 the number of reported cases dropped for the fifth consecutive year, to 4,306, and the report rate per 100,000 people declined to 58.3, the lowest over the past 70 years for both. In total, 162 people died of tuberculosis in Hong Kong last year – two more than in 2016. Undersecretary for Food and Health Dr Chui Tak-yi said the report rate had seen “a sharp 90 per cent reduction” as compared with the 1950s and 1960s, but was still higher than rates in some parts of Europe and the Americas. Explainer: a brief history of TB in Hong Kong, as experts fear global comeback of the disease The incidence rate per 100,000 people was 27 in the Americas and 32 in Europe in 2016, according to the WHO. Centre for Health Protection controller Dr Wong Ka-hing said tuberculosis prevention work still “faced challenges” such as high mobility among those living in neighbouring countries with high rates of the disease, an ageing population and a rising number of patients with chronic illness in Hong Kong. Among the city’s 4,306 cases in 2017, 117 involved Chinese immigrants in the city – the highest number for that group since 2004. Eight cases of tuberculosis confirmed at Hong Kong secondary school Mainland China, with an incidence rate of 64 per 100,000 people, ranked fifth among countries the WHO ranked for tuberculosis. Angola, Bangladesh, Brazil and Cambodia topped the list, whose top 30 also included India, Indonesia , Myanmar, Pakistan, the Philippines , Thailand , and Vietnam . Wong reminded the public that tuberculosis treatment entailed multiple medicines that must be taken for at least six months. He said strict compliance was required for successful treatment.