Medical Officer's annual report [to] Durban Corporation.

  • Durban (South Africa). Public Health Department.
Date:
[1946]
Catalogue details

Licence: Public Domain Mark

Credit: Medical Officer's annual report [to] Durban Corporation. Source: Wellcome Collection.

    19/56 (page 17)
    Equipment. Of the many types of pumps and applicators, those characterised by simplicity of design and operation are preferable. Foci to be treated are often inaccessible and away from electric power, thus nar¬ rowing the field of choice to small hand-operated equipment. Many liquid insecticides have cresyllic or carbolic acid as a base. Pumps must be made of a material not susceptible to the corrosive action of this acid and must be of simple design with spares available for replacement. Summary.—With respect to : (a) Equipment.—Hand-operated, manageable pumps of simple type assuring a good “ wetting ” or “ contact ” spray are preferable ; (7) Material—Any liquid contact spray with a rapid “ knockdown ” factor is suitable. Apathy on the part of the majority of householders in conducting regular and active roach control measures can only be explained on the assumption that existing methods are too “ troublesome” for general adoption. Perhaps insecticidal “ smokes ” used as a fumigant may supply the answer. Departmental control measures comprise regular and systematic spraying of foci such as sewers, storm¬ water drains, gutter-bridges, culverts and the many Municipal-owned and occupied premises. Science has not yet provided private enterprise with the ideal means for solving this problem of the private householder. The Department’s inspectional staff is every ready to advise and demonstrate control measures. Statistical.— Sewer-manholes sprayed Stormwater-manholes sprayed Gutter-bridges sprayed. Water-valves sprayed . D.C. premises treated . Private properties treated Gallons of spray fluid . Total number of foci treated... 70,645 82.507 49.508 60,126 111 21,932 5,776 284,829 Having regard to the fact that upwards of a score of roaches are killed by each treatment, it will be appreciated that the control programme contributes materially in keeping down these pests, but again it must be emphasised :— (1) That the ready and constant co-operation of householders is necessary ; and (2) That the ideal insecticide has not yet been evolved or, at least, become available. Cimex (Bed Bugs).—The control of this pest relates to :— (1) Actual work carried out departmentally ; and (2) Supervision of work carried out by private enterprise. With regard to (1), activities are limited strictly to Municipally-owned or occupied premises, particularly in the Indian Sub-Economic housing schemes. In these schemes it is incumbent upon all tenants, immediately they are allotted a house, to have their furniture and personal effects fumigated by cyanide. The usual practice is to place these articles in one or two rooms of the house and treat with HCN (180 grammes per 1,000 cu. ft.). The programme also includes control work in Native quarters, etc., attached to the larger Municipal institutions, such as beer halls and police barracks. With regard to the supervision of private enterprise, the position is that before the promulgation of the present Government Hydrogen Cyanide regulations, the fumigator was obliged to give 24 hours notice of any intended fumigation. At present, however, departmental supervision is confined to inspection of fumigation registers and the “ follow-up ” of particular operations selected for investigation. Private fumigators have, as a rule, co-operated with the Department in maintaining an efficient fumigation service. D.D.T. and Kindred Preparations.—The Department continues to follow closely all literature and infor¬ mation in regard to these preparations. It is possible that highly important advances in technique and efficiency may be achieved by the use of D.D.T. and Gammexane “ smokes ” which are now under test overseas on a large scale. Sectional equipment has been kept up-to-date to undertake any type of work entailing the use of these preparations. With regard to the efficacy of D.D.T. preparations, sectional experiments have proved that it is an ideal material for the control of slow-moving pests whose harbourages or habitats are restricted to a short radius of personal environment. It is particularly useful in preventing re-infestation of Native quarters and, coupled with preliminary cyanide fumigation, has proved effective in treating recognised harbourages. This Department carried out 153 HCN fumigation treatments whilst private enterprise catered for 4,356 cyanide fumigations. The following is a summary of the Field Hygiene Section’s activities during the year Rodents : Premises trapped for plague index . Baits laid. Traps set... Cynogas used : lbs. Rodents destroyed. Rodents sent to Laboratory, Government. Rodents sent to Laboratory, Field Hygiene Mosquitoes : Larvacide used : gallons . Ditches cleared : yards. Land cleared : acres . Disinfectant used : gallons . Other spraying fluids . Larvae examined in Departmental Laboratory ... Cimex: Premises fumigated by City Health Department Premises fumigated by private enterprise . 930 355,873 18,843 1,709 6,223 326 634 7,856* 600,318 68 281 89* 3,258 153 4,356