Ortho-isopropoxphenyl methylcarbamate (OMS-33) as a residual spray for control of anopheline mosquitos. With special reference to its evaluation in the WHO programme for evaluating and testing new insecticides.

More than 1300 compounds have so far been included in the WHO Programme for Evaluating and Testing New Insecticides, which is designed to disclose compounds that may satisfactorily replace those to which insect vectors of disease have become resistant. The authors describe the successful passage of o-isopropoxyphenyl methylcarbamate (OMS-33) through the first 6 stages of the 7-stage programme that has been established for compounds intended for use against anopheline mosquitos and conclude that this product is suitable for testing in the final stage-large-scale epidemiological evaluation.In operational field trials (at 2 g/m(2)) OMS-33 has been shown capable of controlling Anopheles stephensi (in Iran), An. gambiae and An. funestus (in Nigeria) for 3-4 months, An. albimanus (in El Salvador) for 2-4 months and An. dthali (in Iran) for 2(1/2) months. It has an airborne effect by which anophelines are killed for a considerable time after OMS-33 has been sprayed, even though they do not make contact with a sprayed surface; this quality would appear advantageous in areas where anophelines enter houses and bite man but do not rest long enough on sprayed surfaces to acquire a lethal dose of insecticide or where significant outdoor biting occurs. The observance of simple safety precautions protects occupants of sprayed houses, spraymen and others from danger. Chemical studies have indicated that commercially produced water-dispersible powders of OMS-33 are stable under field conditions of storage and use.

Efectos de la suspensión del rociamiento residual y del paludismo importado en el control de la malaria en Estados Unidos / Effects of suspended residual spraying and of imported malaria on malaria control in the USA

The activities of the National Malaria Eradication Program, a cooperative campaign inaugurated in July 1947 by the United States Public Health Service and certain State and local health agencies, are outlined. Control operations reached their maximal level in 1948, when 1,364,950 dwellings in 13 "malarious" States were sprayed with residual DDT, and the percentage of mosquito control achieved was 83.2

In 1950, only 2,227 cases of malaria were reported as compared with 16,203 in 1947 and 9,797 in 1948. But the return of infected servicemen from Korea caused a temporary increase in the incidence in 1951 and 1952, when the totals were 5,600 and 7,023, respectively. In 1953, however, only 559 civilian cases were reported; of the cases appraised, 28 were of local origin, and, of these, at least 24 are known to have been infected in 1952

The Public Health Service ceased active participation in the Program in 1951, but continued to give technical advice. At the same time, State authorities received Federal support in activating malaria surveillance-and-prevention programs. More selective anti-anopheline activities have replaced residual insecticide spraying, which is now carried out in only a few isolated areas. It is believed that these measures have prevented imported malaria from increasing the diminishing incidence of primary indigenous cases in the USA(AU)

Efectos de la suspensión del rociamiento residual y del paludismo importado en el control de la malaria en Estados Unidos / Effects of suspended residual spraying and of imported malaria on malaria control in the USA

The activities of the National Malaria Eradication Program, a cooperative campaign inaugurated in July 1947 by the United States Public Health Service and certain State and local health agencies, are outlined. Control operations reached their maximal level in 1948, when 1,364,950 dwellings in 13 "malarious" States were sprayed with residual DDT, and the percentage of mosquito control achieved was 83.2

In 1950, only 2,227 cases of malaria were reported as compared with 16,203 in 1947 and 9,797 in 1948. But the return of infected servicemen from Korea caused a temporary increase in the incidence in 1951 and 1952, when the totals were 5,600 and 7,023, respectively. In 1953, however, only 559 civilian cases were reported; of the cases appraised, 28 were of local origin, and, of these, at least 24 are known to have been infected in 1952

The Public Health Service ceased active participation in the Program in 1951, but continued to give technical advice. At the same time, State authorities received Federal support in activating malaria surveillance-and-prevention programs. More selective anti-anopheline activities have replaced residual insecticide spraying, which is now carried out in only a few isolated areas. It is believed that these measures have prevented imported malaria from increasing the diminishing incidence of primary indigenous cases in the USA(AU)