Showing papers by "World Health Organization published in 1991"

Nomenclature and research case definitions for neurologic manifestations of human immunodeficiency virus-type 1 (HIV-1) infection

Abstract: Infection with human immunodeficiency virus-type 1 (HIV-1) has been associated with avariety of neurologic disorders thought to be caused, directly or indirectly, by HIV-1.1-6 Although these disorders have been described clinically, there is no consensus terminology or criteria for diagnosis. To develop consensus nomenclature and case definitions for HIV-1-associated neurologic conditions for research purposes, the American Academy of Neurology AIDS Task Force convened a working group of neurologists, neuropsychologists, psychiatrists, and sociologists that included representatives of the American Neurological Association, the World Federation of Neurology, the International Neuropsychological Society, the National Academy of Neuropsychology, the American Psychological Association, the American Psychiatric Association, the World Health Organization, and the Centers for Disease Control (CDC). These definitions have been developed in conjunction with the International Classification of Diseases-10 (ICD-10, unpublished draft of the World Health Organization) and the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV, unpublished draft of the American Psychiatric Association). Although consistent with the ICD-10, the definitions are not identical. HIV-2 may cause similar disorders, but the neurologic manifestations of HIV-2 are unknown and are not addressed in this article.

Narrow excision (1-cm margin) : a safe procedure for thin cutaneous melanoma

Abstract: We analyzed the results at 8 years of an international, randomized, prospective study carried out by the World Health Organization Melanoma Programme aimed at evaluating the efficacy of 1-cm-margin excision of primary melanomas not thicker than 2 mm. Data for 612 patients were assessable; 305 were randomized to receive 1-cm-margin excision and 307 to receive wide excision (margins of greater than or equal to 3 cm). The major prognostic criteria were similar in the two groups. Breslow thickness was 0.99 mm in the narrow excision group and 1.02 mm in the wide excision group. Disease-free and overall survival rates (mean follow-up period, 90 months) were similar in the two groups. Only four patients had a local recurrence as a first relapse. All underwent narrow excision, and each had primary melanomas thicker than 1 mm.

The pathways to psychiatric care: a cross-cultural study

Abstract: This paper describes the referral pathways taken by 1554 patients newly referred to the mental health services in 11 countries, and documents factors associated with delays in referral. The pathways in centres relatively well provided with psychiatric staff were dominated by general practitioners and to a lesser extent hospital doctors: the relatively less well resourced centres showed a variety of pathways with native healers often playing an important part. Delays were remarkably short in all centres regardless of psychiatric resources, but in some centres we found longer delays on pathways involving native healers. Somatic problems were a common presentation in all centres, and in some centres there was a tendency for patients presenting with somatic problems to have longer delays than those with symptoms of depression or anxiety. The implications of these findings are discussed in the context of an ongoing programme of WHO research activities aimed at improving the quality of mental illness care available in community settings.

Abdominal Obesity and Physical Inactivity as Risk Factors for NIDDM and Impaired Glucose Tolerance in Indian, Creole, and Chinese Mauritians

Abstract: Objective We wanted to determine whether obesity, abdominal fat distribution, and physical inactivity act similarly and independently as risk factors for noninsulin- dependent diabetes mellitus (NIDDM) and impaired glucose tolerance (IGT) in Hindu and Muslim Asian Indians, African-origin Creoles, and Chinese Mauritians. Research Design and Methods We examined a population-based random cluster sample of 5080 adult subjects from the Indian Ocean island of Mauritius. Glucose tolerance was assessed with a 75-g oral glucose tolerance test and World Health Organization criteria. Results Univariate data and multiple logistic regression models indicated that age, family history of diabetes, body mass index (BMI), waisthip ratio (WHR), and physical inactivity conveyed similar risk for NIDDM (and IGT) in each ethnic group. After adjusting for all other factors, Hindu ethnicity conferred additional risk for NIDDM (but not IGT) in men, but in women there were no clear ethnic differences. Although BMI and WHR were independently significant risk factors, WHR conveyed relatively stronger risk for NIDDM than BMI in women, whereas the converse was true in men. For ethnic groups combined, the independent odds ratios for IGT associated with moderate and low physical activity scores (relative to high) were 1.56 and 1.71 ( P P P P Conclusions These data indicate that BMI, abdominally distributed fat, and physical inactivity are important independent risk factors for both IGT and NIDDM in diverse ethnic groups. Attributable risk fractions for Mauritius suggest that populationwide modification of levels of these risk factors could potentially result in substantially lower occurrence of NIDDM (and IGT). Such interventions should be attempted in high-risk populations.

User charges for health care: a review of recent experience.

Abstract: This paper reviews recent experiences with increases in user charges and their effect on the utilization of health care. Evidence from several countries of differences in utilization between rich and poor is presented, and recent accounts of sharp, and often sustained, drops in utilization following fee increases, are presented and discussed. Fee income, appropriately used, represents a small but significant additional resource for health care. Recent national experiences appear to have concentrated on achieving cost recovery objectives, rather than on improving service quality and health outcomes. Appraisal of financing changes must be linked to probable health outcomes. Successful large-scale experience in linking these two is in short supply.

Mycobacterial heat-shock proteins as carrier molecules.

Abstract: We have previously shown that the priming of mice with live Mycobacterium tuberculosis var. bovis (Bacillus Calmette-Guerin, BCG) and immunization with the repetitive malaria synthetic peptide (NANP)40 conjugated to purified protein derivative (PPD), led to the induction of high and long-lasting titers of anti-peptide IgG antibodies, overcoming the requirement of adjuvants and the genetic restriction of the antibody response to the peptide (Lussow et al., Proc. Natl. Acad. Sci. USA 1990. 87:2960). This initial work led us to the following observations. BCG had to be live for priming to lead to the induction of anti-peptide antibodies. Surprisingly, priming with other living microorganisms which chronically infect the macrophage (e.g. Salmonella typhimurium and Leishmania major) also induced anti-peptide antibodies in mice immunized with PPD-(NANP)40 conjugate. It was, thus, hypothesized that molecules expressed during active infection and also known to be highly conserved between species, namely the heat-shock proteins (hsp), could mediate the T cell sensitization required for the production of anti-peptide antibodies. In fact, when the PPD protion of the conjugate was replaced by a highly purified recombinant protein corresponding to the 65-kDa (GroEL-type) hsp of M. bovis, this resulted in the production of anti-(NANP) IgG antibodies in BCG-primed mice, irrespective of the major histocompatibility complex-controlled responsiveness to the (NANP) sequence itself. Further, similar induction of anti-peptide antibody response was also obtained with a recombinant 70-kDa (DnaK-type) hsp of M. tuberculosis, but not with a small molecular mass (18 kDa) of M. leprae. Finally, an adjuvant-free carrier effect for anti-peptide IgG antibody production in BCG-primed mice, was also exerted by the GroEL hsp of Escherichia coli. This finding that hsp can act as carrier molecules without requiring conventional adjuvants is of potential importance in the development of vaccine strategies.

Diabetes in adults is now a Third World problem. The WHO Ad Hoc Diabetes Reporting Group.

Abstract: Since 1988, WHO has been collecting standardized information on the prevalence of diabetes mellitus and impaired glucose tolerance (IGT) in adult communities worldwide. Within the age range 30-64 years, diabetes and IGT were found to be absent or rare in some traditional communities in Melanesia, East Africa and South America. In communities of European origin, the prevalences of diabetes and IGT were in the range of 3-10% and 3-15% respectively, but migrant Indian, Chinese and Hispanic American groups were at higher risk (15-20%). The highest risk was found in the Pima Indians of Arizona and in the urbanized Micronesians of Nauru, where up to one-half of the population in the age range 30-64 years had diabetes. The prevalence of total glucose intolerance (diabetes and IGT combined) was greater than 10% in almost all populations, and was within the range 11-20% for European and U. S. white populations. However, the prevalence of total glucose intolerance reached almost 30% in Arab Omanis and in U. S. blacks and affected one-third of all adult Chinese Mauritians, migrant Indians, urban Micronesians and lower-income urban U. S. Hispanics. In Nauruans and Pima Indians, approximately two-thirds of all adults in the age range were affected. These results lead to three important conclusions. (1) An apparent epidemic of diabetes has occurred--or is occurring--in adult people throughout the world. (2) This trend appears to be strongly related to life-style and socioeconomic change. (3) It is the populations in developing countries, and the minority or disadvantaged communities in the industrialized countries who now face the greatest risk.(ABSTRACT TRUNCATED AT 250 WORDS)

The interrelationship of sexually transmitted diseases and HIV infection: implications for the control of both epidemics in Africa.

Abstract: There is a high burden of sexually transmitted diseases (STDs) in many parts of Africa. As for HIV the highest rates of STDs are found in urban men and women aged 15-35 years. STDs may be responsible for up to 17% of productive life years lost to disease in sub-Saharan urban populations. Despite this heavy burden of STDs however their diagnosis and treatment remain neglected by public health in most of the developing world. Many factors drive the epidemiology of STDs in Africa. The disproportionate number of men relative to women in many cities prompts many men in urban areas to have sex with a core group of prostitutes who facilitate the spread of STDs. In other cities the frequent change of sex partners economic factors access to health services lack of health education health seeking behavior and lack of political will play roles in the spread of STDs. Genital ulcer disease is also more frequent in Africa than in developed countries. The authors discuss the interactions between HIV and other STDs the impact of HIV infection upon other STDs the impact of the HIV/STD interactions upon the HIV and STD epidemics and implications for STD and HIV control programs.

The use of focus groups in social and behavioural research: some methodological issues.

Abstract: The use of focus groups as a qualitative method for rapid assessment is discussed. A focus-group session is an in-depth discussion in which a small number of people (usually 8-12) from the target population discuss topics that are of importance for a particular study or project. Generally the participants are chosen purposively, and it is recommended that they should be homogeneous with respect to characteristics which might otherwise impede the free flow of discussion. Focus groups can be used for idea generation, in conjunction with a quantitative method, or as a primary data-collection method. However, if focus groups are used as a primary data-collection method, their results must be treated with caution. The main advantage of using focus-group discussions during rapid assessment is that they provide in-depth information without requiring full-scale anthropological investigations. The informal group setting is believed to make people feel at ease, encouraging them to express their views freely. However, there are a number of limitations to focus-group discussions. The samples are small and purposively selected, and therefore do not allow generalization to larger populations. In addition, as with other qualitative methods, the chances of introducing bias and subjectivity into the interpretation of the data are high. There are a number of methodological issues which still need to be addressed in order to further develop the method. Little is known about how many discussion sessions are needed to be reasonably sure that most aspects related to the subject of inquiry have been explored.(ABSTRACT TRUNCATED AT 250 WORDS)

Sexual culture, HIV transmission, and AIDS research

Abstract: The spread of the international AIDS pandemic has drawn attention to the urgent need for data on human sexual behavior; yet the absence of an established tradition of theory and method in sex research has limited the development of initiatives in this area. This has been particularly evident in the lack of attention given to the ways in which cross‐cultural differences structure the meaning of sexual experience. While survey research can play an important role in documenting sexual behavior, qualitative research on sexual culture is equally important in order to develop a framework for the comparative analysis of behavioral data. This article seeks to contribute to the development of theory and method in sex research by outlining key research issues and possible methodologies for the qualitative investigation of sexual culture in relation to HIV/AIDS.

An immunogenic Onchocerca volvulus antigen: a specific and early marker of infection

Abstract: Onchocerciasis (river blindness) is a serious health problem and a severe obstacle to social and economic development, especially in Africa. A complementary DNA fragment coding for an Onchocerca volvulus antigen (OV-16) was cloned and expressed in the plasmid vector pCG808fx. Immune responses to this O. volvulus-specific recombinant antigen were detectable in patients with documented onchocerciasis; the antibody response was also detectable at 3 months and at more than 1 year before infection could otherwise be detected in humans and in chimpanzees experimentally infected with O. volvulus third-stage larvae.

Minor and Trace Elements in Human Milk from Guatemala, Hungary, Nigeria, Philippines, Sweden, and Zaire Results from a WHO/IAEA Joint Project

Abstract: Concentrations of As, Ca, Cd, Cl, Co, Cr, Cu, F, Fe, Hg, I, K, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Sn, V, and Zn were determined in human whole milk samples from Guatemala, Hungary, Nigeria, Phillippines, Sweden, and Zaire; in most of these countries, three groups of subjects representing different socioeconomic conditions were studied. Analytical quality control was a primary consideration throughout. The analytical techniques used were atomic absorption spectrophotometry, atomic emission spectrometry with an inductively coupled plasma, colorimetry, electrochemistry, using an ionselective electrode and neutron activation analysis. The differences between median concentrations of Ca, Cl, Mg, K, Na, and P (minor elements) were lower than 20% among the six countries. Among trace elements, concentrations observed in Filipino milk for As, Cd, Co, Cr, Cu, F, Fe, Mn, Mo, Ni, Pb, Sb, Se, and V were higher than for milk samples from other countries. The remaining five countries showed a mixed picture of high and low values. In the case of at least some elements, such as, F, I, Hg, Mn, Pb, and Se, the environment appears to play a major role in determining their concentrations in human milk. The nutritional status of the mother, as reflected by her socioeconomic status, does not appear to influence significantly the breast milk concentrations of minor and trace elements. Significant differences exist between the actual daily intakes observed in this study and current dietary recommendations made by, for example, WHO and the US National Academy of Sciences. These differences are particularly large (an order of magnitude or more!) for Cr, F, Fe, Mn, and Mo; for other elements, such as, Ca, Cu, Mg, P, and Zn, they amount to at least a factor 2. In the opinion of the present authors, these findings point to the need for a possible reassessment of the dietary requirements of young infants, with respect to minor and trace elements, particularly for the elements Ca, Cr, Cu, F, Fe, Mg, Mn, Mo, P, and Zn.

Establishment of resistance to Leishmania major infection in susceptible BALB/c mice requires parasite-specific CD8+ T cells

Abstract: Although CD4+ T cells are generally accepted to be responsible for the determination of resistance to infection in experimental murine cutaneous leishmaniasis, a contribution of CD8+ lymphocytes to immunity can be demonstrated under certain well-defined conditions. Normally highly susceptible BALB/c mice can be rendered resistant to infection with Leishmania major promastigotes by a single injection of monoclonal anti-CD4 antibodies at the beginning of infection. Mice treated in such a way can heal their primary cutaneous lesions and acquire immunity to subsequent challenge infection. Both the resolution of the primary infection and the induced state of immunity to reinfection in these mice is shown to be dependent upon the anti-leishmanial effector functions of CD8+ T cells. Furthermore, in contrast to control infected BALB/c mice, which are unable to mount a delayed-type hypersensitivity (DTH) response to viable parasites, mice cured as a result of treatment with anti-CD4 antibodies in vivo exhibit a strong DTH response, which can be significantly reduced by injection of either anti-CD4 or anti-CD8 monoclonal antibodies prior to antigenic challenge with viable promastigotes. Moreover, increased numbers of specific CD8+ T cells, able to transfer Leishmania-specific DTH responses, were found in lymphoid organs of BALB/c mice rendered resistant to infection by immunointervention with anti-CD4 monoclonal antibodies at the beginning of infection. Neutralization in vivo of interleukin 4 during the course of infection in BALB/c mice also enables these otherwise susceptible mice to resolve their cutaneous lesions and to decrease the parasite burden in infected tissues. CD8+ T cells are required for both of these beneficial effects. Taken together, these results indicate that in the immune BALB/c mouse, as in the normally resistant CBA mouse, CD8+ lymphocytes are involved in the elimination of L. major and in the establishment and maintenance of immunity against infection with this parasite.

Community‐oriented medical education: what is it?

Abstract: Summary. The pressing need for this com­ munication has emerged from the author's experience in conducting educational workshops, seminars and meetings for the ori­ entation of health professionals in community­ oriented medical education. Many questions are raised and many statements made which clearly indicate that the term 'community-oriented medical education' (COME) is still misunder­ stood. It carries a different meaning for different people. Many give it their own meaning and attach to it their own interpretations. This has resulted in wide propagation of the wrong concepts to the detriment of promoting the approach. (It is worth noting that 'community medicine' has over the years suffered the same fate. Is it because both terms include the word 'community', which often has a poor image for much of the medical profession?) An attempt is made here to clarify the situation by a process of questions and answers, the questions being those frequently asked as such or posed in the form of statements. They are by no means exhaustive. Seven major such questions are addressed with reference to personal experience and the literature.

Depot‐medroxyprogesterone acetate (dmpa) and risk of edometrial cancer

Abstract: The use of depot-medroxyprogesterone acetate (DMPA), a long-acting progestational contraceptive, in relation to risk of epithelial ovarian cancer was examined in a hospital-based case-control study conducted in Mexico and Thailand. Women with histologically confirmed epithelial ovarian cancer (n = 224) diagnosed between 1979 and 1988 were compared with hospital controls (n = 1,781) matched on age, hospital and year of interview. Overall, 9.8% of cases and 12.9% of controls had ever used DMPA. The relative-risk (RR) estimate in women who had ever used DMPA, controlling for the confounding effects of number of live births and oral contraceptive use, was 1.07 (95% CI 0.6, 1.8). No consistent patterns of increasing or decreasing risk were noted according to duration of use, time since first or most recent use or age at first use of DMPA. These results suggest that the risk of epithelial ovarian cancer is not altered by the use of DMPA.

Estimation and projection of adult AIDS cases: a simple epidemiological model.

Abstract: Many HIV/AIDS (acquired immunodeficiency syndrome) models have been developed to help our understanding of the dynamics and interrelationships of the determinants of HIV (human immunodeficiency virus) spread and/or to develop reliable estimates of the eventual extent of such spread. These models range from very simple to very complex. WHO has developed a simple model for short-term projections of AIDS, details of which are presented here along with results obtained using the model to estimate and project AIDS cases for the USA, sub-Saharan Africa, and south/south-east Asia. WHO has also developed, based on the model described in this paper, a computer program (Epi Model), which will enable the user to easily change the values of any of the variables required by the WHO model.

Dietary intake of pesticide residues: Cadmium, mercury, and lead

Abstract: Information on the dietary intake of chemical contaminants has been obtained from institutions participating in GEMS/Food. Contaminants studied include certain organochlorine and organophosphorous pesticides, PCBs, cadmium, mercury, and lead. The intakes are compared with toxicologically acceptable intake levels established by international expert groups. In most cases, dietary intakes of organochlorine and organophosphorous pesticides are well below the Acceptable Daily Intake (ADI) of the respective pesticide. Of some 21 countries providing information on the average dietary intake of cadmium, only in one case is the Provisional Tolerable Weekly Intake (PTWI) exceeded. Several countries identified cereals and cereal products and root and tuber vegetables as the main contributors to the dietary intake of cadmium. For mercury, all reported intakes are below the PTWI of methylmercury. The contribution of fish to the total intake of mercury varied from 20% to 85%, depending on the country. Therefore, the general assumption that fish is the main contributor to the total dietary intake of mercury may, at times, not be justified. Average dietary intake of lead exceeding or approaching the PTWI are reported for adults and infants and children in some countries. Foodstuffs which contribute most to the intake of lead vary from country to country, and have been identified as being alternately drinking water, beverages, cereals, vegetables and fruit.

Response Bias in a Case-Control Study: Analysis Utilizing Comparative Data Concerning Legal Abortions from Two Independent Swedish Studies

Abstract: Independent reports of legal abortions in two Swedish epidemiologic studies of breast cancer in young women, covering the same women and overlapping the same time period, have been compared in order to estimate a putative response bias. One study used case-control methods and obtained data by retrospective interviews from 317 cases and 512 controls. The other study was based on objectively documented information froma nationwide registry covering legally induced abortions. Analysis demonstrated a ratio between the odds ratios from the two studies of 1.5 (95 percent confidence interval 1.1-2.1) and an observed ratio of 22.4 (p less than 0.007) between underreporting of previous induced abortions among controls relative to overreporting among cases. This response bias may explain the tendency toward increased risk of breast cancer which, according to several case-control studies, appears to be associated with induced abortion.

Transmission of HIV, hepatitis B virus, and other bloodborne pathogens in health care settings : a review of risk factors and guidelines for prevention

Abstract: This article discusses the risk factors for HIV hepatitis B virus (HBV) and other blood-borne pathogen transmission in the health care setting and the specific guidelines for its prevention Reports confirmed that the transmission of HIV HBV as well as other blood-borne pathogens in health care settings have caused considerable public health concern and constitute infectious hazards in certain settings Transmission of blood-borne pathogens were believed to be from patient to patient patient to health care and rarely from health care worker to patient Although the risk of infection is certainly real it is largely preventable it may occur due to the use of unscreened blood for transfusion the use of improperly sterilized medical and dental equipment accidental punctures with contaminated needles and exposures to non-intact skin or mucus membrane to infectious materials The risk of transmission depends on the dose of pathogen contaminated and the frequency or probability of exposure to infectious material General guidelines for the prevention of transmission in the health care settings are given including the concept of "universal precautions" the need for adequate supplies of sterile equipment; the reduction of unnecessary injections and transfusions; and the appropriate use of hepatitis B vaccine In addition areas of research and development are highlighted to provide both the health care workers and the patients an improved understanding on the risks of transmission of these blood-borne pathogens

Epidemiology and social costs of low back pain and fibromyalgia.

Abstract: Low back pain and fibromyalgia represent two of the most common disorders in developed countries. On the whole, up to 75% of the general population has, at some time, suffered from low back pain. A percentage ranging between 5 and 10% of them develops a chronic illness. In most countries, the incidence rate per year of low back pain is 5%. Most low back pain episodes occur between the ages of 25 and 55 years. Most studies have not found any clear influence between genders and frequency of low back pain. There is a relationship between low back pain and occupation, with those who have physically demanding jobs being more at risk. As regards fibromyalgia, the prevalence rates range between 6 and 20%, with a higher frequency among females and between the ages of 25 and 55 years. The direct and indirect costs of low back pain approach $24 billion per year in the U.S. It is in view of its high prevalence among populations of developed countries, of its heavy psychosocial and financial implications, and of the burden imposed on health services, that low back pain represents a severe public health problem.

Maternal anthropometry for prediction of pregnancy outcomes: Memorandum from a USAID/WHO/PAHO/MotherCare meeting

Abstract: The memorandum is an abbreviated version of a prepared report on maternal anthropometry which summarizes the general recommendations of a consensus of 50 experts on field applications and priority research issues in developing countries. Consensus was reached at a meeting on Maternal Anthropometry for Prediction of Pregnancy Outcomes held in Washington D.C. in April 1990. 15 general recommendations are identified for field applications and research priorities. Specific recommendations differentiating field applications from research priorities are provided for prepregnancy weight weight gain in pregnancy height arm circumference and weight for height and body mass index. For example the discussion of arm circumference indicates that it is useful as an indicator of maternal nutritional status in nonpregnant women because of its correlation with maternal weight or weight for height. During pregnancy it is useful as a screen for risk of low birth weight (LBW) and late fetal and infant mortality. Maternal arm circumference has been found to be stable during pregnancy in developing countries and is independent of gestational age. Field applications involve the use 1) to assess the nutritional status of pregnant and nonpregnant women 2) to screen women at risk of poor maternal stores postpartum because it reflects maternal fat and lean tissue stores for instance 3) to screen women and refer to facilities for a more thorough assessment of nutritional risk and 4) to assess the extent of undernutrition in an area particularly for surveillance. Community level workers especially birth attendants (TBAs) should be trained and have access to arm circumference tapes. The technology is simple enough also for use by women in the home. Cutoff points for assessing biological risk are fairly consistent across developing country populations and range between 21-23.5 cm. Routine monitoring during pregnancy is not necessary because the changes are too small to detect. Where prepregnancy weight is unavailable and weight is monitored arm circumference may serve as a proxy for prepregnancy weight. All women of childbearing age should be measured. Research priorities are to explore the functional significance with women of difference body compositions (fat versus lean upper arm) the relationship to pregnancy related outcomes arm changes relative to stages throughout the reproductive period and to weight changes different instruments such as color-coded tapes or 1 tape for arm measurement and uterine height combinations of different measurements the relationship with prepregnancy weight and the development of arm circumference in weight gain charts as a proxy for prepregnancy weight.