PUBLIC HEALTH
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as far as possible and include all well-populated parts of the Colony.
In order to delay as long as possible the development of resistance on the part of the malaria vectors, Anti-malaria Mixture (oil) has, since the early part of 1957, been more widely used as the general purpose larvicide, and Gammexane Dispersible Powder (P520), the larvicide previously em- ployed, has been reserved for areas where the application of oil is contra-indicated, e.g. agricultural lands. Another fea- ture which has been encountered is that Gammexane Disper- sible Powder at the usual dosage is in many instances no longer effective against the breeding of the non-malarial culicine mosquito, particularly Culex fatigans, which fre- quently occurs in, or adjacent to, potential anopheline breed- ing places.
Tuberculosis. Tuberculosis remained the principal health problem during the year. X-ray surveys indicate that approximately 2% of the adult population are suffering from active pulmonary tuberculosis, while the death rate still exceeds 100 per 100,000 population. The total number of deaths ascribed to tuberculosis during the year was greater than last year due to abnormal figures recorded during the influenza epidemic in April and May. It appears that some headway is being made in reducing the number of deaths from tuberculosis in infants.
Control measures are based upon the protection of infants and young children by B.C.G. vaccination and reducing the number of infectious cases in the community by large scale ambulatory chemotherapy backed by minimal hospital provi- sion, and, more recently, by treating tuberculin positive children with isonicotinic acid hydrazide even in the absence of overt disease.
The principal efforts in the B.C.G. campaign are con- centrated upon new-born babies, over one-third of whom are now vaccinated within a few days of birth. Vaccination
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