179. In the crowded areas where the houses are packed with humans and their belongings, the periodical cleansing of premises is a most important factor in the prevention of the spread of this disease. All the furniture, moveable fittings and household goods are removed from the rooms and cubicles and all floors and woodwork washed down with an emulsion of soap and kerosene oil. This is done either by the Sanitary staff or by the occupiers under the general supervision of the district inspector; in addition, accumulated rubbish of all kinds is cleared away and the premises thoroughly searched for rat-holes. Altogether 211,657 floors were dealt with during the year.
180. Thirty members of the cleansing staff were employed in setting traps, bird-lining boards, distributing barium carbonate baits, and collecting rodents which had been taken living or dead. By far the greatest number of rats were taken dead from the numerous rat reception bins or tins which are placed in convenient situations throughout the two cities. The Chinese take exception to the rats being found on their premises by the Sanitary staff, probably through fear of extra sanitary measures being taken against them, and it is not uncommon for them to kill the rodents found in the Government traps and to throw the carcases into the reception bins. The total number of rats collected was 174,239, of which 12,792 only were taken alive. All rats collected were sent to the Public Mortuaries for examination by the Medical Officer in charge.
181. During the year, no rats were found to be plague-infected.
Preventive Measures Against Smallpox.
182. Under the Vaccination Ordinance, all Public Vaccinators are under the Director of Medical and Sanitary Services, who is Superintendent of Vaccination. As Registrar of Births and Deaths, the Director is responsible for ensuring the vaccination of all children whose births are registered.
183. During the year, 279,420 persons, or nearly one-third of the total population, were vaccinated.
The following table shows the principal bodies engaged in vaccinating and the number of operations performed by each.
The Public Vaccinators 51,054 The Government Hospitals 2,997 The Chinese Public Dispensaries 37,875 The St. John Ambulance Brigade 187,494 Total 279,420