ACCORDING to Dr. Selwyn Clarke, the director of medical services, Hong Kong, in his annual report for 1939, the colony's chief health problem is the large number of Chinese refugees from the Sino-Japanese War. In July 1939 the number of persons entering the colony exceeded the number leaving it by 327,833. Many of the immigrants were destitute, ill–nourished and diseased, and the overcrowded conditions in which they lived were a most serious menace to public health. The largest number of deaths in 1939 were caused by non–tuberculous diseases of the respiratory system. Tuberculosis came next, the majority of the deaths being due to the pulmonary form. 24 per cent of 1,500 refugees whose blood was examined showed a malarial infection. There were more than 9,000 cases of beriberi, 800 cases of cholera and 3,000 of influenza during the year.