Showing papers by "World Health Organization published in 1983"

From the national institutes of health. Summary of a workshop on the clone concept in the epidemiology, taxonomy, and evolution of the enterobacteriaceae and other bacteria.

Abstract: Participants in this workshop included Mark Achtman, Max-Planck Institut ffir Molekulare Genetik, Berlin; Alan G. Barbour, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Rocky Mountain Laboratory, Hamilton, Mont; Michael Barile, US Food and Drug Administration, Bethesda, Md; Louis S. Baron, Walter Reed Army Institute of Research, Washington, DC; Mark Beaubien, Fogarty International Center, NIH; Thomas M. Buchanan, University of Washington, Seattle; B. Wesley Catlin, The Medical College of Wisconsin, Milwaukee; P. Patrick Cleary, University of Minnesota, Minneapolis; Mitchell L. Cohen, Center for Infectious Diseases, Centers for Disease Control (CDC), Atlanta; Alan S. Cross, Walter Reed Army Institute of Research; J. P. Duguid, University of Dundee Medical School, Scotland; Robert Edelman, NIAID; John J. Farmer, III, Center for Infectious Diseases, CDC; Samuel B. Formal, Walter Reed Army Institute of Research; Carl E. Frasch, US Food and Drug Administration; Peter Gemski, Walter Reed Army Institute of Research; Robert C. Goldman, National Institute of Arthritis, Diabetes, and Digestive and Kidney Diseases, NIH; Carolyn M. Hardegree, US Food and Drug Adminstration; James B. Kaper, University of Maryland School of Medicine, Baltimore; Dennis J. Kopecko, Walter Reed Army Institute of Research; Loretta Leive, National Institute of Arthritis, Diabetes, and Digestive and Kidney Diseases; Bruce R. Levin, University of Massachusetts, Amherst; Myron M. Levine, University of Maryland School of Medicine, Baltimore; Frits and Ida Orskov, International Escherichia and Klebsiella Centre, Statens Seruminstitut, Copenhagen; John B. Robbins, US Food and Drug Administration; Bernard Rowe, Central Public Health Laboratory, London; R. Bradley Sack, The Johns Hopkins University, Baltimore; J. C. Sadoff, Walter Reed Army Institute of Research; Rachel Schneerson, US Food and Drug Administration; Robert K. Selander, University of Rochester, New York; Richard Silver, US Food and Drug Administration; David H. Smith, University of Rochester, New York; Lucy S. Tompkins, University of Washington, Seattle; Kaye Wachsmuth, Center for Infectious Diseases, CDC; the late Lewis Wannamaker, University of Minnesota Medical School, Minneapolis; T. S. Whittam, University of Rochester, New York; Richard A. Wilson, Pennsylvania State Bethesda, Md. Investigators from Europe and the United States discussed epidemiologic, pathophysical, genetic, and evolutionary problems relating to the clone concept. T e workshop was opened by Dr Mark Beaubien, Acting Director of the Fogarty International Center, and by Dr Frits Orskov, who noted that Herbert John Webber first used the word clone in 1903 to designate a population in which all members have been derived from one and the same progenitor by nonsexual multiplication. For present purposes, the word clone will be used to denote bacterial cultures isolated independently from different sources, in different locations, and perhaps at different times, but showing so many identical phenotypic and genetic traits that the most likely explanation for this identity is a common origin. Dr Orskov pointed out that the concept of a clonal connection between isolates from a clear-cut outbreak of disease caused by a phenotypically well-characterized pathogen has probably always been accepted, even though the word "clone" itself may not have been used. In recent years, however, the clone concept has also been applied to bacteria (such as many serotypes of Escherichia coli) that usually do not cause clearcut outbreaks or epidemics. Dr Orskov concluded by expressing the hope that recently developed techniques would make it possible to characterize phenotypes within the many bacterial groups, thereby allowing a more precise definition of bacterial clones.

Prevalence of diabetes and impaired glucose tolerance in the biracial (melanesian and indian) population of fiji: a rural-urban comparison

Abstract: Rural-urban and ethnic comparisons of impaired glucose tolerance and diabetes mellitus were made in the biracial population of Fiji in 1980. No statistically significant differences existed in age-standardized impaired glucose tolerance prevalence between rural and urban groups or between Melanesians and Indians. The age-standardized prevalence of diabetes in the rural Melanesian male population was one-third that of the urban male population (1.1 vs. 3.5%). In females, there was a sixfold rural-urban difference (1.2 vs. 7.1%). By contrast, rural and urban Indians had similar rates (12.1 vs. 12.9% for males; 11.3 vs. 11.0% for females). Standardization of two-hour plasma glucose for age and obesity did not eliminate the rural-urban difference in plasma glucose concentration for Melanesian males and females. The results in Melanesians confirm previously reported rural-urban diabetes prevalence differences, and suggest that factors other than obesity, such as differences in physical activity, diet, stress, or other, as yet undetermined, factors contribute to this difference. The absence of a rural-urban difference in diabetes prevalence in Indians may suggest that genetic factors are more important for producing diabetes in this ethnic group, or that causative environmental factors such as diet operate similarly upon both the rural and the urban populations.

Associations among cataract prevalence, sunlight hours, and altitude in the himalayas

Abstract: The relationship between cataract prevalence, altitude, and sunlight hours was investigated in a large national probability sample survey of 105 sites in the Himalayan kingdom of Nepal, December 1980 through April 1981. Cataract of senile or unknown etiology was diagnosed by ophthalmologists in 873 of 30,565 full-time life-long residents of survey sites. Simultaneously, the altitude of sites was measured using a standard mountain altimeter. Seasonally adjusted average daily duration of sunlight exposure for each site was calculated by a method which took into account latitude and obstructions along the skyline. Age- and sex-standardized cataract prevalence was 2.7 times higher in sites at an altitude of 185 meters or less than in sites over 1000 meters. Cataract prevalence was negatively correlated with altitude (r = -0.533, p less than 0.0001). However, a positive correlation between cataract prevalence and sunlight was observed (r = 0.563, p less than 0.0001). Sites with an average of 12 hours of sunlight exposure had 3.8 times as much cataract as sites with an average of only seven hours of exposure. Sunlight was blocked from reaching certain high altitude sites by tall neighboring mountains.

The WHO collaborative study on strategies for extending mental health care, II: The development of new research methods.

Abstract: Teams in seven developing countries under sponsorship of the World Health Organization have been carrying out collaborative operational research on providing mental health care through primary health care services. New techniques of identifying mental disorders in children and adults have been developed and tested. Methods of assessing the skills and attitudes of health workers toward mental health work and of gauging community attitudes toward mental illness have also been developed. Results have been directly applied in planning better mental health care. The authors conclude that cross-cultural collaborative research is effective in improving mental health care for those in greatest need.

Measles: Summary of Worldwide Impact

Abstract: Nearly every measles infection results in well-recognized clinical disease. In nonimmunized populations almost every child will get measles early in life. The universality of the disease in nonimmunized communities, particularly those in the developing world, has led to a more or less passive acceptance of measles as an unavoidable risk of early life. The clinical spectrum of measles ranges from a mild, self-limiting illness to a fatal disease. Conditions encountered mainly in the developing world, e.g., unfavorable nutrition, high risk of concurrent infection, and inadequate case management -- particularly at home -- favor the development of complications and adverse outcome. Conversely, good clinical management of an otherwise healthy child, a situation seen mostly in the developed world, greatly influences the course of the disease. Hence many in the medical profession believe that measles is a mild disease except among populations living under particularly unfavorable conditions. Measles vaccine is effective in preventing disease in the individual and in controlling it in the community if it is given at the critical age when maternal antibodies wane and the risk of natural infection increases sharply and if a high immunization rate is maintained in the target population. The experience with immunization, particularly in sub-saharan Africa, is rewarding: mothers who had previously accepted measles as an unavoidable risk clamour for immunization of their children once its effectiveness has been demonstrated. No reason exists for measles to claim its present toll of morbidity and mortality. With extension of the Expanded Programme on Immunization of the World Health Organization, the impact of measles should progressively decline.

Colonization factor antigens I and II and type 1 somatic pili in enterotoxigenic Escherichia coli: relation to enterotoxin type.

Abstract: Enterotoxigenic Escherichia coli (ETEC) isolates from 36 persons with acute traveler's diarrhea from whom no other pathogens were recovered were tested (after no more than three subcultures) for the presence of colonization factor antigens I and II (CFA/I and CFA/II) and type 1 somatic pili. CFA/I or CFA/II was identified in 7 of 10 strains with heat-labile and heat-stable enterotoxins (LT+/ST+), but in only 2 of 12 LT-/ST+ (P less than 0.05) and 0 of 14 LT+/ST- (P less than 0.02) strains. CFA pili were not found among 74 non-enterotoxigenic E. coli strains. Type 1 somatic pili were demonstrable in 42% of the 36 ETEC and in 49% of the 74 non-enterotoxigenic E. coli isolates. The nine ETEC isolates bearing a CFA were serially subcultured on 10 consecutive days and retested for CFA and toxin. After five subcultures only one strain had lost a CFA, but after 10 passages three strains were negative: two lost CFA/I and one lost CFA/II. The strain that lost CFA/II became negative for both LT and ST as well and was found to lack a 48- and a 60-megadalton plasmid. The two strains that lost CFA/I also became negative for ST, but plasmid analysis revealed no plasmid loss. Disappearance of the CFA/I phenotype without loss of a plasmid can be explained by phase variation, as exhibited by type 1 somatic pili, or by rearrangement of base sequences in the CFA/I plasmid genome. If purified pili vaccines are to provide broad-spectrum protection against ETEC diarrhea, the search must be intensified to identify the antigens responsible for adhesion to intestinal mucosa in the many ETEC strains that lack CFA/I and CFA/II.

The adverse consequences of heavy Trichuris infection

Abstract: Sixty-seven children with heavy Trichuris trichiura infection (Group A) were compared to 73 control children of similar socio-economic status but with light or no T. trichiura (Group B), for nutritional status, rates of concomitant bacterial and protozoal, and symptoms and clinical signs associated with heavy T. trichiura infection. Anoscopy was used to determine heavy T. trichiura infection. Measurements and physical examination were done on Group A on admission to and discharge from hospital; 46% were seen on follow-up visit two to eight months later. Children in Group B were seen only once. There were significant differences for nutritional status (p < 0·01) and rates of bacterial and protozoal co-infection (p < 0·01) and a significantly greater rate of invasive amoebiasis in Group A. After treatment, nutritional parameters of Group A children improved significantly, symptoms and clinical signs decreased and there was also a significant decrease in the rate of concomitant bacterial and protozoal infection. Subgroups of Group A children, with and without concomitant enteropathogens, revealed that infection with Entamoeba histolytica and bacterial enteropathogens had had no significant impact on clinical and nutritional status.

Clinical Aspects in Man

Abstract: The other chapters in this book present knowledge based mainly on experimental work; in contrast, this chapter dealing with the clinical aspects of trichinosis is based primarily on clinical observations and experience. Here I wish to quote Dr. C.C. Booth (1980), who said that “those who decry the observational aspect of clinical research should recall that astronomy, whose scientific credentials have never been questioned, is an entirely observational science.” In trichinosis, the links between clinical research and basic science are strong. Much of the modern knowledge and techniques used in parasitology, immunology, and clinical pathology have been introduced for better understanding of trichinosis as a disease. On the other hand, clinical studies of human trichinosis have promoted interest in the basic biological problems such as differences in various Trichinella spiralis strains. In the last two decades, great progress has been made in understanding the pathological mechanisms, symptoms, and signs of human trichinosis as well as in more rational treatment of the infection. However, many aspects of clinical trichinosis still remain unknown or vague, due in part to the limited possibilities for studying trichinosis in man.

Visual ictal phenomena in a case of Lafora disease proven by skin biopsy.

Abstract: Summary: A seizure with visual symptoms was recorded for the first time in a patient with Lafora disease. The utility of skin biopsy as a diagnostic tool is discussed. RESUME Dans le present travail une crise epileptique a semeiologie visuelle enregistree chez un patient qui presente la maladie de Lafora est decrite pour la premiere fois. L'utilite de la biopsie cutanee pour le diagnostic est discutee. RESUMEN En esta comunicacion se documenta por primera vez el registro de un ataque con sintomas visuales en un caso de enfermedad de Lafora. Tambien se discute la utilidad de una biopsia de piel como metodo di-agnostico. ZUSAMMENFASSUNG In dieser Arbeit wird ein Anfall mit optischen Symptomen bei einem Patienten mit Lafora-Krankheit zum ersten Mai dokumentiert. Die Nutzlichkeit der Hautbiopsie als Diagnostikum wird diskutiert.

The Clonal Nature of Enteropathogenic Escherichia coli Strains

Abstract: Enteropathogenic Escherichia coli belonging to O groups O111 and O55 and isolated from cases of infantile diarrhea in 26 countries all over the world during 1950-1960 were examined for their outer-membrane protein (OMP) patterns; nine O:H serotypes of O111 and 11 serotypes of O55 were represented. Characteristic biotypes have earlier been described as closely associated with the most common O:H serotypes: O111:H2, O111:H12, O55:H6, and O55:H7. Different OMP patterns characterized each of the common O:H serobiotypes. The OMP patterns can be looked upon as another set of stable phenotypic characters in addition to the serotype antigens and the fermentative characters. The description of geographically widely spread, stable sero-/bio-/OMP types supports the concept that the typical enteropathogenic E coli strains also have a clonal connection.

Food-borne Hepatitis A: Recommendations for Control

Abstract: Because hepatitis A virus (HAV) is transmitted by the fecal-oral route [1], contamination of food or water has been an important means of spreading infection. Hundreds of foodborne outbreaks of hepatitis A have been associated with significant mortality and morbidity [2]. Approximately 1,000 food handlers with hepatitis A were reported yearly to the Centers for Disease Control (CDC) between 1975 and 1980 and accounted for approximately 7% of reported cases per year. The identification of such individuals raises important questions about the risk of transmission and the need for prophylaxis with immune globulin (IG). During outbreaks, IG is frequently first administered far past the two-week period in which it is effective [3], a delay that can generally be attributed to the mechanics of outbreak recognition and mass IG administration; however, administering IG to the entire population at risk after a food handler is found to have hepatitis A appears to be unwarranted, since only a handful of hepatitis A outbreaks are recognized each year, even though ,',1,000 food handlers are reported to contract hepatitis A yearly. In an attempt to clarify these issues, we examined the epidemiologic characteristics of 20 foodborne outbreaks of hepatitis A that occurred in the United States during 1968-1980, in which a source case or presumed source case was identified. These outbreaks were identified by a review of all published outbreaks reported to the CDC.

Response to tetanus immunization in onchocerciasis patients.

Abstract: Fifty-five people were examined for tetanus antitoxin level two months after immunization with a single 0.5 ml dose of concentrated tetanus toxoid vaccine; only 7.1% of patients infected with onchocerciasis became immunized, whereas 44.5% were immunized in the control group. These results are consistent with previous observations of a reduced level of both cell-mediated and humoral immunity in patients heavily infected with parasitic diseases, especially onchocerciasis. This study raises doubts about the efficacy of immunization in young adult age groups and re-emphasizes the need for immunization in infancy.

Management of clinical trials in developing countries.

Abstract: Clinical trials need to consider specifics in trial circumstances when novel measures to improve health call for assessment in developing countries. Predictions regarding safety and efficacy under regional conditions deriving from data of trials in affected populations in another part of the world cannot always be accepted as reliable indicators of future regional performance. The primary objective should be to reveal new information. This discussion of the management of clinical trials in developing countries focuses on the following: the protocol; staff and supervision; locations and logistics; the use of a pilot study; drugs and compliance; and ethics. At an initial workshop a planning group with the broadest possible representation draws up a protocol. Ideally the protocol is never imposed but is developed through extensive consultation and coordination. Its initial objective is an agreement on how to make a specific study feasible. Initial goals should be restricted to answering a few simple but meaningful questions. Information in the study protocol includes: aims and objectives; precise definitions of clinical variables; detailed description plus frequency and timing of clinical procedures laboratory tests and so forth; case report forms; consent forms and any warning notices written in the local language; work manuals for the pharmacist of drug supervisor; the treatment allocation procedure and individual treatment charts; the labeling code emergency code breaking and referral procedures; precise guidelines for evaluation and management of known adverse reactions; and an investigational data brochure. Selection of a competent dependable and enthusiastic principal investigator available for the full duration of the study is essential. Suitable trial sites should be carefully chosen to avoid conditions that might prevent application of adequate scientific standards. In case of doubt about the logistical feasibility starting with a trial run of the test procedures or with a pilot study using an established drug should be considered in order to detect potential problems concerning availability of scientific and technical expertise equipment or reagents. It is necessary to check national clearances for investigating new agents. Permits may be required from a review body a manufacturer or from an authority. All needed drug supplies should be obtained at once together with information on stability under expected storage conditions. An independent measure of patient compliance needs to be agreed upon. Projects should be reviewed as well as approved by an independent local group practicing the highest standards of protection of the rights of the individual. Data collection begins with identification of subjects by photographs of faces in addition to careful records of name household domicile and occupation.

On vagrancy and psychosis.

Abstract: Paradoxically, due to recent mental health legislation, the mentally handicapped of the developed world find themselves in the same situation as the majority of those in the developing world who never had contact with a mental health service. A survey of the literature and of the situation in Egypt and Lesotho suggests marked coincidence of vagrancy and chronic mental illness. In both the developed and developing world, adequate services to support these people are lacking.

Decreased Microfilarial Load and its Effect on the Calculation of Prevalence and the Rate of False Negatives in the Detection of Onchocerciasis

Abstract: It has been shown in the epidemiological evaluation of onchocerciasis that the method of taking two or more snips per person contains information about the probabilities of false negatives which can be extracted and used to improve the prevalence estimates. Using the method of maximum likelihood, one can obtain expressions for estimating the prevalence, adjusted for the false negatives, and for estimating the proportion of false negatives. The variances of all estimates are also available, making confidence interval estimation possible.

Primary health care in the context of rapid urbanization.

Abstract: A review of demographic trends and health and social problems in the fast growing urban areas of the world indicates that in the future increasing numbers of people will be living in precarious socioeconomic conditions which impede the achievement of health. It is estimated that from 4.4 billion in 1980 the worlds population will increase to 6.2 billion by the year 2000. The urban population will increase from 1.8 to 3.2 billion during the same period over 2 billion of which will be in developing countries. The rapid and often uncontrollable demographic growth of cities especially in the developing world stimulates the demand for resources intensifies their utilization and creates an intolerable pressure on the urban infrastructure and physical environment. A number of action oriented projects to combat disease and contamination have been successful. Projects in Addis Ababa Ethiopia Colombo Sri Lanka Hyderabad India Guayaquil Ecuador Lima Peru and Rio de Janeiro have been implemented under a partnership among WHO UNICEF the Netherlands Aid Agency the World Bank and other international organizationals and governments. These projects all emphasize the fundamental role of community organizations especially that of women; low-cost technology and the need to mobilize and efficiently use locally available resources; an ecological multisectoral concept of health whereby action concerning the environment education income generation and the availability of food all with a powerful disease preventive potential carry equal if not greater weight than the efforts to provide the population with health centers or implement curative practices. All these projects are focused on marginal groups; many were initiated by imaginative individuals or groups with a considerable amount of social orientation and motivation and often at least in the beginning without the support of governments nongovernmental or international organizations. It is important to study these projects in their accomplishments and failures; to help describe them and disseminate related information when appropriate; and to promote political and technical support for those which are successful so that they can rapidly come out of the experimental/demonstration phase and be expanded to become part of routine programs.

Primary Health Care as a Practical Means for Measles Control

Abstract: In 1977 the 30th World Health Assembly affirmed that the main social target of governments and the World Health Organization in the coming decades should be "the attainment by all citizens of the world by the year 2000 of a level of health that will permit them to lead a socially and economically productive life." The International Conference on Primary Health Care in Alma-Ata, USSR in 1978 identified primary health care as the fundamental approach for attaining this social target. What relevance do these pronouncements have concerning the worldwide control of measles? Is primary health care a prerequisite to control? Is it sufficient? It is concluded that little chance for global measles control exists unless national policy makers and health workers at all levels adopt the general approach of primary health care but that it is unlikely this approach, by itself, will assure measles control. Special efforts to reduce or stop measles transmission will also be required. In most developing countries at least, the goal of measles control can best be pursued as part of a broader program to reduce morbidity and mortality from several diseases of children preventable by immunization.

Effects of early thiamin deficiency and subsequent rehabilitation on the cholinergic system in developing rat brain.

Abstract: The effects of thiamin deficiency during pregnancy and/or lactation on brain cholinergic system in rat pups were studied. Dietary rehabilitation for a period of 5 weeks from the 28th day was instituted to study possible 'catch-up' in the brain acetylcholine levels. Brain acetylcholine level was found to be significantly decreased on the 21st and 28th days in pups of the dams fed thiamin deficient diet during gestation and lactation, whereas it was decreased on the 28th day in pups of the dams fed thiamin deficient diet during lactation. Activities of cholinergic enzymes remained unaltered in both the deficient groups. Subsequent dietary rehabilitation was found to reverse the deficits in brain acetylcholine levels.