premises under study, 288 were cleared of rats, and presumably of typhus, and 34 remained infested. The largest area freed of rats was 25 square miles.

Plague: Surveillance was continued in port cities of the western United States where plague has occurred. Studies in the San Francisco Bay area indicated an intermingling of wild and domestic rodents that permitted an interchange of their common fleas. Other findings suggest that "permanent" reservoirs of enzootic plague exist in the continental United States and in Hawaii.

Q-Fever: Studies revealed that the greatest amount of infectious material in sheep was discharged during the lambing period. It was found that these materials, even though dried, remained infectious for many weeks. At present, the infection is presumed to be airborne. Studies have shown that the usual commercial pasteurization temperatures do not destroy all Q-fever organisms which may be found in milk from infected cows. Temperatures of 145° F. for 30 minutes were needed to kill all rickettsiae in experimentally contaminated milk.

Rabies: Rabies infection has been found in three genera of insectivorous bats in Florida. Studies to determine the significance of findings related to bat rabies in the United States are being conducted. A joint program of surveillance and control of rabies in wildlife was initiated in New Mexico to include a search for rabies infection in bats in the southwestern part of the United States.

Ringworm: In a study of the spread of ringworm infections between animals and humans, lesions were reported in 10 human contacts of 31 dogs and cats infected with Microsporum canis. Four species of dermatophytes were isolated from 47 percent of samples of animal hair received from 13 States and from Canada.

Schistosomiasis: Cooperative surveys with the Commonwealth of Puerto Rico Department of Health to measure the rates of schistosomiasis among school children show that the incidence of the disease in different geographic areas varies from 0 to 27 percent. In some schools, rates up to 53 percent were encountered.

Division of Dental Public Health

The Division of Dental Public Health provides technical assistance to State and local health departments and conducts studies designed to develop, test, or improve dental public health practices.

In working toward a solution of dental health problems, the Division utilizes knowledge gained from its own studies and develops competence in the use of procedures advanced by others. Dental programs are conducted in 46 States, but many of these are of a minimum nature; hence, there is continuing request for professional and technical as

sistance. Through consultation and field activities, the Division meets these requests on a limited basis.

CONSULTATIVE ACTIVITIES

A working document was developed which provides a practical method for States to use in developing dental health programs. The document, which culminates several years of effort, outlines the elements which must be considered in planning and carrying out successful State dental health programs.

Pilot studies in specialized fields are being conducted in 20 States. These serve as a stimulus to State and local health departments in improvement of dental health programs.

Assistance was given to the Commission on Chronic Illness in developing the dental parts of the Baltimore Health Survey, including the preparation of a set of dental questions for the household interview survey and physical examination card. The Division will also participate in the physical examination of persons interviewed as a part of the multiple screening procedure.

FIELD PROJECT ACTIVITIES

The Grand Rapids water fluoridation project continued into its 10th year, in cooperation with the National Institute of Dental Research. Beneficial effects were exemplified by the 62-percent reduction in dental caries in 7-year-old children, and a 45 percent reduction in tooth decay in 14-year-olds who have been drinking fluoridated water part of their lives. Intervening age groups showed corresponding reductions.

Two studies have been initiated to determine the dental service requirements of children receiving the full benefit of naturally fluoridated water in Cambridge, Md., and the changing dental needs of children living in Gainesville, Fla., whose supply has been fluoridated since 1949. Other studies dealt with the effectiveness of topically applied caries preventives, the development of more precise measures for determining the prevalence of periodontal disease in child populations, and the fluid intake of infants and youth.

The problem of a variable fluoride intake related to differences in temperature and other climatic factors is being studied in several of the Western States. Current investigations are aimed at determining the optimum concentration in lower temperature areas.

The pilot defluoridation studies in Bartlett, Tex., and Britton, S. Dak., are continuing. During the year improved regeneration procedures have reduced the fluoride concentration of finished water to a desirable level. The procedures employed are now believed to be economical and practical enough for general adoption.

Division of International Health

The Public Health Service continued its participation in international public health work during 1954 through both the international health agencies and agencies of the United States Government operating abroad, such as the Foreign Operations Administration. Through the Division of International Health, the Public Health Service maintains active relationships with the World Health Organization and the Pan American Sanitary Organization. Matters of policy are conducted through the Department of State, and technical matters directly with the two organizations.

During the year the Service furnished members of official delegations and participated in the formulation of policy and preparation of instructions to the delegations to the following meetings: Seventh World Health Assembly; sessions of the Directing Council of the Pan American Sanitary Organization; meetings of the Executive Committee of the Pan American Sanitary Organization; WHO Regional Committee for the Western Pacific; and WHO Regional Committee for the Americas.

The Chief of the Division and the International Health Representative, hold Presidential appointments as United States Representative and Alternate, respectively, on the Executive Board of the World Health Organization. Under these appointments they serve in their personal capacities and not as representatives of the Government.

During the year the Division worked out arrangements in this country in connection with the WHO program to establish internationally recognized nonproprietary names for drugs moving in international commerce. Arrangements were completed to provide for review of proposed nonproprietary names by interested groups in this country.

In addition, procedures were worked out to provide for adequate review of monographs proposed for inclusion in the International Pharmacopoeia. Volume I of this publication was issued in October 1951 by the World Health Organization, and volume II was under preparation. At a series of meetings attended by representatives of the American Pharmaceutical Association, the U. S. Pharmacopoeia, the National Formulary, and the American Homeopathic Pharmacopoeia, industry, and government, it was agreed that a United States Committee on International Standards for Drugs be established to provide competent and representative previewing of monographs proposed for inclusion in the International Pharmacopoeia.

Initially the membership of the Committee includes representatives of the U. S. Pharmacopoeia and National Formulary Revision Committees, the American Homeopathic Pharmacopoeia Committee on

Manufacture, the Combined Contact Committee of the American Drug Manufacturers Association and American Pharmaceutical Manufacturers Association. The American Pharmaceutical Association provides administrative support for the Committee. WHO now sends each monograph to the American Pharmaceutical Association in its capacity as administrative staff for the Committee. The Committee decides on proper distribution for review and forwards comments to WHO for consideration.

VOLTA RIVER BASIN DEVELOPMENT

In April the Special Commissioner of the Preparatory Commission for the Development of the Volta River Basin in Gold Coast, Africa, and his special consultant were in Washington to discuss problems in medical entomology, preventive medicine, occupational health and housing in connection with public health, medical care, and housing problems of the Volta River Development Authority. These conference were arranged by the Division of International Health.

COOPERATION WITH FOA

Early in the year the Director of the Foreign Operations Administration and the Secretary of Health, Education, and Welfare set forth the principles governing relationships between FOA and constituents of the Department. Following this, detailed operational guides and operating agreements, covering the nature and extent of Public Health Service and Children's Bureau participation in FOA programs, were developed.

Public Health Service responsibility in FOA programs was considerably increased when the Service was asked to accept staffing and programming responsibility in Latin American countries on the same basis as for other countries throughout the world. In previous years, these functions had been handled directly by the Institute of InterAmerican Affairs.

Representatives of the Division of International Health, the Children's Bureau, and the Public Health Division of FOA prepared a statement of health program priorities for international technical assistance programs. This statement was transmitted to all FOA field missions as a basic guide for fiscal year 1954 programs and for development of the budget for fiscal year 1955. It was later adopted as a basic guide for continuing use in planning and developing technical assistance programs in health.

A significant project was the work done on specifications and standards for insecticides and spraying equipment. A number of problems had developed in connection with DDT, which is used in substantial quantities in malaria control programs, and which in some instances had been received overseas in unusable condition. The

Division arranged discussions of these problems with major DDT manufacturers, the National Agricultural Chemical Association, the Department of Agriculture, and the Communicable Disease Center. The Center agreed to develop specification for DDT to be used in the technical assistance programs, and a continuing review is under way. Malaria control operations are being carried on in 17 countries with the assistance of FOA and PHS staffs. Approximately 100 million people were protected against malaria by these programs during the fiscal year. Surveys have shown that industrial production increases when workers and their families are free from attacks of malaria. Tremendous savings are effected through increases in earning power and in land value and through decreases in medical expenses and individual indebtedness. In Mysore, India, for example, it was found that such savings in the course of a year amounted to 93 times the amount of money spent to protect the community. During the year approximately 11,000 tons of DDT, and some small amounts of dieldrin were purchased for use in FOA malaria programs, and further increases in malaria control programs are anticipated.

Although designed primarily for the control of malaria, these programs also have other beneficial effects. For example, in Pakistan, kala-azar has also been effectively controlled through the DDT spraying program, and in Thailand, where dieldrin has been used, there has been a remarkable reduction in the transmission of filariasis.

Technical assistance programs in health were continued in 38 countries during the year. Toward the end of the year Saudi Arabia requested that such assistance in that country be discontinued, and arrangements were undertaken to withdraw the health personnel assigned to that mission. A new program was inaugurated in Surinam. During the year 100 professional health workers were recruited for assignment to overseas missions. Of this number, 23 are medical officers, 36 are sanitary engineers or sanitarians, 25 are nurses, and 16 are in other professional categories.

TRAINING OF FOREIGN NATIONALS

The Division prepared or assisted in the programs arranged for 792 foreign health workers from 66 countries who were in this country for study or observation. This number is 42 fewer than those who were trained in fiscal year 1953, but 168 more than in 1952.

During the year, 48 schools, 29 clinical centers, and 10 inservice training organizations were utilized in the placement of participants for training and observation. Many Federal, State, and local agencies, as well as private and voluntary organizations, cooperated in the training of foreign students and visitors. Of the 792 health workers, 352 came from the Far East, 261 from the Western Hemisphere, and the remainder from Europe, Africa, and the Middle East.