Malaria as anthropo-ecosystem. Part III: Diversity of MAES

Diversity being one of the main characteristics of Malaria Anthropo-Ecosystem (MAES) is reflected in time and space. Temporal diversity of MAES generally may be divided into two types--long time periods usually on a global scale, and various local fluctuations expressed as malaria periodicity. Geographical confinement of MAES is determined by interactions of various elements of the latter with biotic and abiotic components of the environment. The diversity of the MAES within climatic zones of South and South-East Asia is shown to be of many types of sub-systems depending, apart from climatic conditions, on types of human activity in those ecosystems.     

Malaria as anthropo-ecosystem. Part VI: Demographic subsystem (DSS)

Demographic Subsystem (DSS) comprising structure, distribution, along with its dynamic process has been identified to influence Malaria as Anthropo-Ecosystem (MAES) broadly in two ways. Innate characters of some essential elements of DSS viz. growth, age and sex composition, infants, children, young and old adults, non-pregnant and pregnant and lactating mothers exert direct influence while other elements, viz. spatial distribution, density, configuration of settlements and migration are influenced by environmental factors and affect MAES indirectly. Attempt has been made to discuss each of these factors in the light of present knowledge and available data.     

Malaria as anthropo-ecosystem (MAES): Part V. Self-regulation and stability of MAES

In biological ecosystems, population tends to fluctuate above or below asymptotic level or the 'carrying capacity'. Self-regulation is achieved by extrinsic, that is, environmental limiting factors and intrinsic, that is, physiological and genetic factors. In Malaria Anthropo-Ecosystem (MAES) which is much more intricate and complex system, Plasmodium being endoparasite is required not only to interact with intrinsic factors of its vertebrate and invertebrate host but also to regulate itself to environmental factors to which its both the hosts are subjected. Attempt has been made to provide, on the basis of present knowledge, the probable explanation of self-regulatory mechanisms from molecular, cell, organ/organism, population/community levels of vertebrate and invertebrate hosts which give stability to MAES as a whole system.     

Part I. General practitioner-specialist relationship

This article is the first of a two-part series that seeks to explore the relationship and interaction between general practitioners (GPs) and medical specialists. A historical account of the medical profession is given, beginning from the tripartite division (i.e. the physicians, surgeons or barbers and the apothecaries), the Apothecaries Act of 1815, and the Medical Act of 1858. An account is also given of factors that exacerbated the division and friction between GPs and specialists, and how general practice developed in Australia. The role of the GP is stated as the provision of primary care, preventive care, patient-centred care, continuing care, comprehensive care, and community-based care to individuals and their families. The role of the specialists on the other hand is that of a consultant to advise GPs who carry on the management after the patient leaves the specialist. The dynamics of the GP-specialist relationship are discussed in relation to power, interdependence, morale, public image, education and training, and support from the Colleges, and we conclude by discussing the importance of collaboration between professions.     

Prevention and screening. Part I: General principles.

Currently, a substantial part of clinical practice is involved with health maintenance and disease prevention. However, there continue to be deficiencies in the delivery of preventive care, and it is sometimes difficult to identify which interventions are effective--for lack of randomized clinical trials--and the theoretical basis of this approach is not always clear. In this paper, the first in a series of two, we will present the general conceptual principles of preventive medicine, starting with levels of prevention and followed by the criteria for selecting a preventive intervention. Regarding the latter, the characteristics of the disease to be screened and the respective screening test will be discussed, as well as therapy for positive cases. Finally, we will discuss the possible consequences of screening for disease. In our second paper, to be published in the next issue, we will present guidelines for the critical appraisal of an article about screening.     

Malaria as Anthropo-Ecosystem. Part IV. Adaptation of elements of MAES

Adaptations have been recognized as an essential facets of evolution. These broadly cover two types exemplified by change (adjustments) and that leads to creation of new species. The former is generally in response to environmental factors, while the others are genetic and heritable and enable the population to continue its existence. These are also accompanied by biological and behavioural changes. In the study of MAES, adaptations appear to be main mechanism which facilitate the dynamics of the malaria system in time and space. Schematically, three broad groups of resultant factors of adaptations within MAES. viz. genetical, biological and environmental have been identified and briefly discussed with regard to their diversity in all the three elements of MAES.     

Heart failure in patients seeking medical help at outpatients clinics. Part I. General characteristics

BACKGROUND: During the last decade, the beneficial changes in lifestyle and in medical care increased average life expectancy, particularly in patients with chronic diseases such as hypertension and coronary heart disease. Unfortunately this also increased the number of patients, particularly among the elderly, who are susceptible to complications of these conditions such as heart failure. Uncontrolled hypertension is known to be a primary cause of heart failure and is also known to be very prevalent and frequently uncontrolled in the Polish population. AIM: To estimate the prevalence and characteristics of heart failure among patients of 65 years and older seeking medical care in outpatient clinics in Poland. METHODS: The study is a cross-country epidemiological project in which 417 physicians from outpatient clinics were asked to register 50 consecutive patients aged 65 years and above seeking medical care for any cause. Information on case history, physical examination (diagnosis of heart failure, NYHA class, heart failure symptoms), laboratory tests (resting ECG, chest X-ray, echocardiogram) and data concerning pharmacology management during the 2 weeks prior to the index visit was obtained. RESULTS: Over 5 months, 19877 eligible patients (7324 men and 12553 women) presented to the 417 participating physicians (90% physicians registered 46-50 patients). Among the patients, 53% were diagnosed with heart failure (3901 men and 6678 women), prevalence did not differ by gender. Among patients with heart failure there were 38% of men in NYHA class III or IV and 34% of women. Coronary heart disease was a predominant cause of heart failure in 87% of men (26% of cases with isolated coronary heart disease, 53% with concomitant hypertension and 8% with other diseases), while percentages for women were 80% (15%, 61% and 4%, respectively). Isolated hypertension was a further cause of heart failure in 8% of men and 13% of women. Cardiac arrhythmia was found in approximately 20% of patients, enlargement of heart size in 32% of patients and peripheral leg edema in 54% of men and 64% of women. These symptoms increased with age. Chest X-ray revealed cardiomegaly in 68% of men and women and increased cardiothoracic ratio (>50%) in approximately 40% of patients. From resting ECGs, cardiac arrhythmia was recorded in 21% of patients with heart failure, with atrial fibrillation as a predominant disorder (19%). Left ventricular hypertrophy on resting ECG was noted in 42% of men and women and old myocardial infarction or cardiac ischemia was diagnosed in 71% of men and 66% of women. CONCLUSIONS: (1) Heart failure was diagnosed in over half of outpatients aged 65 and older; in more than a third of these it was NYHA class III and IV. (2) Outpatients with heart failure had a high frequency of co-existing diseases such as arrhythmia, coronary heart disease and hypertension.     

Part II. General practitioner-specialist referral process

This is the second of two articles that explore the general practitioner (GP)-specialist relationship. In this article, we explore the nature of the referral process, beginning with referrals frequently made by GPs in Australia and reasons for referral to specialists. In Australia, GPs commonly refer patients to specialists, particularly orthopaedic surgeons, ophthalmologists, surgeons and gynaecologists for a variety of reasons, including diagnosis or investigation, treatment and reassurance (reassurance for themselves as well as reassurance for the patient). GPs will choose a specialist after considering a variety of factors, such as the specialist's medical skill, their previous experience with the specialist, the quality of communication between them, office location and patient preferences. The referral is generally made by telephone or by letter, the latter of which is known to vary significantly in content and quality. The specialist, GP and patient expectations of the referral and the consultation process are also described. Specialists expect the GP to provide information about the problem to be addressed and adequate patient history, GPs expect a clear response regarding diagnosis and management as well as justification for the course of action, and patients expect clear communication and explanation of the diagnosis, treatment and follow-up requirements. When these expectations remain unmet, GPs, specialists and patients end up dissatisfied with the referral process.