bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cyclospora and cyclosporiasis
Authors: Kelly Paul , Lainson Ralph 
Published: February 2020

Abstract
Most species of Cyclospora (Protozoa: Apicomplexa: Eimeriidae) are parasites of various reptiles and mammals. C. cayetanensis, which probably infects only humans, is transmitted by way of resistant oocysts voided in the faeces and contaminating food or water. Distribution is worldwide, particularly in regions with a low level of hygiene. Clinical presentation is with explosive outbreaks of acute diarrhoea, with this infection now regarded as an important causative agent of traveller’s diarrhoea. Diagnosis is dependent on detection of oocysts in faeces by direct examination or in stained faecal smears. Aside from supportive care, treatment with trimethoprim–sulfamethoxazole has proved effective in eliminating the parasite in immunocompetent patients, but relapses are common in those with AIDS. Prevention is by ensuring good general hygiene, and in areas of high endemicity water should be boiled before drinking or use in preparation of fruits/vegetables that are to be eaten raw.
Sarcocystosis (sarcosporidiosis)
Authors: Cooper John E. 
Published: February 2020

Abstract
Sarcocystosis is characterized by the invasion of various tissues by protozoa of the genus Sarcocystis. S. hominis (intermediate host domestic cattle) and S. suihominis (domestic pig) are the most significant to humans, to whom they are transmitted by ingestion of uncooked beef or pork. Camel meat can be a significant source of S. cameli in Arabia. Humans and other primates serve as either intermediate or final host: (1) intermediate host—presence of cysts in muscle is usually asymptomatic, but might cause myositis or myopathy; detected on clinical examination or muscle biopsy; (2) final host—can be asymptomatic or cause fever and gastrointestinal upset; oocysts or sporocysts can be detected in faeces. There is no specific treatment. Prevention is by not eating uncooked meat from any animal and by improving food hygiene in poorer countries.
Giardiasis and balantidiasis
Authors: Eckmann Lars , Heyworth Martin F. 
Published: February 2020

Abstract
Infection with Giardia intestinalis, a common flagellate protozoan that colonizes the lumen of the small intestine, is acquired by ingesting environmentally resistant cysts of the parasite, typically in water or food, or after contact with faecal material from infected individuals. Strains of the parasite that can potentially infect humans are also harboured by various mammals, including dogs and cattle. Manifestations include watery diarrhoea, abdominal discomfort, distension and pain, nausea and vomiting, weight loss, and malabsorption, with the infection typically being persistent and severe in individuals with certain immunodeficiencies. Chronic G. intestinalis infection can lead to micronutrient deficiencies, and impairment of growth and cognitive development in children.
Leishmaniasis
Authors: Bryceson Antony D.M. , Lockwood Diana N.J. 
Published: February 2020

Abstract
Leishmaniasis is caused by parasites of the genus Leishmania, which are transmitted to humans from human or animal reservoirs by the bites of phlebotomine sandflies. In places the disease is common and important, with perhaps 500,000 cases of visceral leishmaniasis and 1.5–2 million cases of cutaneous leishmaniasis worldwide each year. Diagnosis is by demonstration of leishmania organisms in tissue smears or biopsy material by microscopy, culture, or detecting leishmaniai DNA by polymerase chain reaction. As an imported disease, cutaneous leishmaniasis is common in travellers, military personnel, and immigrants coming from endemic areas, while the diagnosis of the less common visceral leishmaniasis is frequently overlooked. Prevention is by controlling reservoir hosts and sandfly vectors, or by avoiding bites by vectors. There is no vaccine.
Lymphatic filariasis
Authors: Knight Richard 
Published: February 2020

Abstract
Wuchereria bancrofti, Brugia malayi, and B. timori are mosquito-borne lymphatic-dwelling nematode parasites that are important causes of morbidity, disability, and social stigma in tropical and subtropical countries. The total population at risk is now estimated to be 856 million in some 52 countries where these infections are endemic. In 2000 before systematic control programmes 120 million people were infected, of whom about 40 million had clinical disease and some 80 million had hidden lymphatic damage. Bancroftian filariasis due to W. bancrofti, which has no animal reservoir, accounts for 90% human infections worldwide; it was introduced into the Americas from Africa by the Atlantic slave trade.
Cysticercosis
Authors: Garcia Hector H. , Gilman Robert H. 
Published: February 2020

Abstract
Cysticercosis, infection by larvae of the pork tapeworm Taenia solium, is the most common helminthic infection of the human central nervous system. It accounts for up to 30% of all seizures and epilepsy in endemic countries, and travel and immigration now lead to its more frequent presentation in industrialized countries. Ingestion of raw or undercooked pork can lead to infection with the T. solium cysticercus, formerly known as ‘Cysticercus cellulosae’, which is an encysted immature tapeworm. Once attached to the person’s small intestine, the head, or scolex, evaginates from the cysticercus, anchors in the intestinal mucosa and develops segments (proglottids) to become an adult tapeworm. Only by ingesting T. solium ova can humans develop cysticercosis. The commonest syndromes are late-onset epilepsy or intracranial hypertension. Diagnosis is based on brain imaging studies (CT or MRI) and supported by highly specific serology.
Liver fluke infections
Authors: Andrews Ross H. , Khuntikeo Narong , Sithithaworn Paiboon , Petney Trevor N. 
Published: February 2020

Abstract
Liver flukes, otherwise known as trematodes, are leaf-like hermaphroditic flatworms. In certain parts of the world, the hepatobiliary system of humans is commonly infected by flukes of the genera Clonorchis and Opisthorchis and occasionally by other species. Humans acquire liver fluke infection by the ingestion of viable metacercariae that are found in second intermediate hosts through raw or partially cooked food, predominately cyprinid fish. These infections are usually diagnosed by finding eggs in the faeces. The diseases caused by liver flukes range from asymptomatic, mild disease to fatal bile duct cancer. Currently the drugs of choice for treatment of liver fluke infection are praziquantel and triclabendazole.
Lung flukes (paragonimiasis)
Authors: Silachamroon Udomsak , Vanijanonta Sirivan 
Published: February 2020

Abstract
Paragonimiasis is an infection by flukes of the genus Paragonimus, with foci of disease in Asia, Africa, and Central and South America. Humans acquire infection by eating metacercariae in improperly cooked freshwater crabs or crayfish. Acute inflammatory and allergic symptoms are rarely serious and usually resolve spontaneously. Chronic manifestations may be (1) pulmonary—most remarkably with a chronic, productive cough with jam-like, brownish-red sputum; and (2) extrapulmonary—most importantly in the central nervous system, often presenting with seizures. Diagnosis is by demonstrating ova in sputum, stool, or pleural fluid. Serology can be used to support the diagnosis, especially in extrapulmonary paragonimiasis. Treatment with praziquantel is almost always effective. Prevention is by health education and the mass treatment of infected people in an endemic area.
Intestinal trematode infections
Authors: McGregor Alastair 
Published: February 2020

Abstract
It is notoriously difficult to estimate the prevalence of intestinal trematode infection, but the most widely accepted figures suggest that 40–50 million people worldwide are infected with at least one of these organisms. Most of these infections are found in tropical South and East Asia, mostly as a result of local culinary practice. The most important intestinal flukes are Fasciolopsis buski and members of the families Echinostomatidae and Heterophyidae. Infection is acquired through the ingestion of the second intermediate host—undercooked freshwater fish, molluscs, frogs, or vegetation contaminated with live metacercariae. Fasciolopsis buski, one of the largest (at 20–77 mm) and most important flukes, is acquired by ingestion of contaminated water plants. Heavy infections may cause abdominal discomfort and diarrhoea, but most infections are entirely asymptomatic. Praziquantel is the drug of choice for all of these infections, which can be prevented by thoroughly cooking potentially infected foodstuffs.
Nonvenomous arthropods
Authors: Paul John 
Published: February 2020

Abstract
Most arthropods are harmless, but there is a select group of medically significant species. Invertebrates with jointed limbs belong to the phylum Arthropoda. Most of the medically important arthropods are in the classes Insecta (insects) or Arachnida (spiders, ticks, mites, scorpions). Some members of the class Chilopoda (centipedes) may bite humans, and some of the larger members of the Crustacea (crabs, lobsters) may cause injury with pincers or spines. Categories of medical significance include: envenoming by bites or stings; allergic reactions to bites, stings, hairs, or inhaled allergens; transmission of infectious agents; infestation; the pain and trauma from bites or penetrating spines; phobia and delusory parasitosis. Arthropods may cause nuisance by their presence or the noises they may make, or by being perceived as unhygienic. It is helpful to identify the species involved, although this may not always be possible, so generic approaches can help the management of problems.
Pentastomiasis (porocephalosis, linguatulosis/linguatuliasis, or tongue worm infection)
Authors: Warrell David A. 
Published: February 2020

Abstract
Pentastomida are dioecious, obligate parasites that are currently grouped in subclass Branchiura (fish lice and cycloids) of class Maxillopoda, subphylum Crustacea, phylum Arthropoda. Common names are ‘pentastomes’ (referring to two pairs of hooks above the mouth that give the impression of five stomata) or ‘tongue worms’ (alluding to the tongue-like appearance of some, such as adult Linguatula). Adult pentastomes inhabit the upper respiratory tracts of their end hosts (vertebrates such as reptiles, fish, birds, and mammals) where they feed on blood and other tissues. Their larvae infect internal organs of vertebrate or arthropod intermediate hosts. Pentastomes appear to have coevolved with other maxillopodan/branchiuran parasites and their vertebrate hosts. There are about 100 living species in the orders Cephalobaenida (e.g. genus Raillietiella) and Porocephalida (e.g. genera Linguatula, Armillifer, Porocephalus, Leiperia, and Sebekia).
Epidemiology of sexually transmitted infections
Authors: Mabey David , Vas-Falcao Anita 
Published: February 2020

Abstract
Although accurate incidence figures are not available in most countries, sexually transmitted infections (STIs) are a large cause of morbidity worldwide. The burden falls especially heavily on women and infants, with up to half a million perinatal deaths attributable to syphilis annually. Mobile populations, those with many sexual partners, and those whose partners have many partners are at increased risk, and the prevalence of treatable STIs is many times higher in poor populations. Other STIs, especially those that cause genital ulceration, increase the risk of HIV transmission. In Western countries, the reported incidence of many STIs fell during the 1980s and 1990s, probably as a result of changes in sexual behaviour resulting from the HIV epidemic, but has increased subsequently. Although accurate data are not available from most low- and middle-income countries (LMICs), there is no doubt that STIs are more prevalent in the developing world.
Sexual behaviour
Authors: Mercer Catherine H. , Johnson Anne M. 
Published: February 2020

Abstract
Discussion of sexual lifestyle and the ability to take a sexual history are relevant to many types of clinical practice. The age at which people first have sex has decreased and the age at which people start cohabiting has become later in recent decades, increasing the time available to accumulate sexual partners and thus be at risk of sexually transmitted infections (STIs), including human immunodeficiency virus (HIV). While many people have few partners, a small proportion of the population has many. People with many partners are most at risk of STIs, but there are many other influences including the gender, age, and ethnicity of their partners and the type of sexual practice. This chapter covers the adverse consequences of sexual behaviour (including STIs and unintended pregnancy), and initiatives to encourage reducing partner numbers, using condoms and effective contraception, and engaging in less risky practices.
Vaginal discharge
Authors: Nyirjesy Paul 
Published: February 2020

Abstract
Vaginal symptoms are a frequent source of discomfort and distress for many women. Bacterial vaginosis, vulvovaginal candidiasis, and trichomoniasis are considered the most common causes in premenopausal women, but atrophic vaginitis and non-infectious disorders seem to occur more often in menopausal women. Self-diagnosis and syndromic management, although increasingly encouraged in many parts of the world, are fraught with inaccuracy. A proper diagnosis depends on a thorough history, examination, and readily available tests in the clinic. Ancillary tests to be considered in selective circumstances include culture for yeast, culture or nucleic acid amplification testing (NAAT) for Trichomonas vaginalis, Neisseria gonorrhoeae, or Chlamydia trachomatis, and Gram stain or (rarely) maturation index. Once a proper diagnosis is obtained, appropriate treatment can be selected.
Pelvic inflammatory disease
Authors: Ross Jonathan D.C. 
Published: February 2020

Abstract
Pelvic inflammatory disease (PID) is an infection of the endometrium, fallopian tubes, and adnexae caused by a wide variety of bacteria, including Chlamydia trachomatis, Neisseria gonorrhoeae, and genital tract bacteria, most notably anaerobes. PID is often asymptomatic but clinical manifestations can range from mild pelvic pain and tenderness to severe peritonitis. Pelvic abscess formation is a serious infectious complication. However, only about 5% of patients with PID have a fever or severe infectious manifestations. An accurate clinical diagnosis of PID is difficult and it is commonly confused with other pelvic conditions, including ectopic pregnancy, appendicitis, and rupture or torsion of an ovarian cyst. Antibiotic therapy is aimed primarily at C. trachomatis, N. gonorrhoeae, and anaerobic bacteria, with prompt identification and treatment of PID recommended in an attempt to reduce the 15% rate of tubal infertility and 40% risk of chronic pelvic pain following this infection.
Principles of contraception
Authors: Haider Zara 
Published: February 2020

Abstract
There are many contraceptive methods available (increasing year on year) which can be classified as: hormonal and non-hormonal, longer lasting, and those with a shorter duration of action, reversible and irreversible. No contraceptive method is 100% effective (apart from abstinence) and where there is potential risk of conception due to unprotected sex or an error with a contraceptive regimen, the patient must be informed about methods of emergency (post-coital) contraception, the most effective being the post-coital intrauterine device (PCIUD). Education of the public about the benefits of contraception is vital and must be done in a timely way (e.g. through school sex education, media, and online resources).
Environmental medicine, occupational medicine, and poisoning—Introduction
Authors: Ayres Jon G. 
Published: February 2020

Abstract
The environment, both occupational and beyond, can affect health in many ways, adversely as well as beneficially. While to date many of these effects have been well understood, most specifically for the work environment, the importance of the wider environment as a cause of ill health has been less well studied on the basis that there is not much one can do about general exposures, such as the weather, or specific events, such as volcanic eruptions, apart from deal with the direct effects. However, increasing awareness of the importance of the environment on health, such as exposure to air pollution (both indoor and outdoor) and the short-, medium-, and long-term effects of climate change, has resulted in better understanding of interventions that can improve health or at least abrogate deleterious effects. This section discusses these aspects in detail.
Occupational and environmental health
Authors: Agius Raymond , Sen Debasish 
Published: February 2020

Abstract
Occupational diseases are those for which work or, specifically, exposures in the workplace are necessary causes. The most prevalent occupational diseases in developed countries today are musculoskeletal and psychological disorders (usually stress-related conditions), but generally occupationally related malignancies (e.g. mesothelioma related to asbestos exposure) have the most serious outcomes. The proportion of all cancers attributable to occupational exposures is about 4%, with occupationally related cancers almost exclusively concentrated in manual workers aged 20 or over in sectors such as mining, agriculture, and industry. When presented with a patient whose illness might possibly have been caused or aggravated by work or by other environmental factors, the physician can usefully adopt an approach similar to that used for determining causation in epidemiological studies; the key issues being the temporality, reversibility, exposure-response, strength of association, and specificity of the illness with exposure to the factor in question.
Aviation medicine
Authors: Bagshaw Michael 
Published: February 2020

Abstract
Travel by air is a safe means of transport, but puts people at various physiological risks and is a potential means of spreading infectious disease. Physiological risks associated with flying include hypoxia, as atmospheric pressure falls with altitude. The minimum cabin pressure in commercial passenger aircraft (565 mm Hg, 75.1 kPa) brings a healthy individual’s arterial P along the plateau of the oxyhaemoglobin dissociation curve until just at the top of the steep part, but does not cause desaturation. By contrast, people with respiratory disease and a low arterial oxygen pressure may desaturate, which can be overcome by administering 30% oxygen, this being equivalent to breathing air at ground level. There is no evidence that the pressurized aircraft cabin itself encourages transmission of disease, and recirculation of cabin air is not a risk factor for contracting symptoms of upper respiratory tract infection.
Heat
Authors: Stroud Michael A. 
Published: February 2020

Abstract
Rising body temperature triggers behavioural and physiological responses including reduction in physical activity, alterations of clothing, skin vasodilatation, and sweating. Heat-related illness is relatively common, especially with high humidity or prolonged physical activity. Risk can be reduced by acclimatization with repeated heat exposure, but some individuals seem to be particularly susceptible. Clinical presentations of heat-related illness include (1) ‘heat exhaustion’—the commonest manifestation, with symptoms including nausea, weakness, headache, and thirst. Patients appear dehydrated, complain of being hot, and are flushed and sweaty. Treatment requires rest and fluids, given orally or (in severe cases) intravenously. (2) ‘Heat stroke’ victims often complain of headache, may be drowsy or irritable, and may claim to feel cold. Core temperature is usually 38–41°C, but the patient is shivering with dry, vasoconstricted skin. Treatment requires (a) aggressive rapid cooling; (b) close biochemical monitoring; (c) supportive care for organ failure. There is significant mortality.
Radiation
Authors: Meara Jill 
Published: February 2020

Abstract
Ionizing radiation has sufficient energy to break chemical bonds and produce charged ions in living tissue. These changes might cause cell death, but breaks of both strands of a DNA molecule that do not kill a cell can be a precursor of cancer. Excluding medical exposures, natural radiation accounts for most human exposure, which produces health effects that might be (1) stochastic, where the probability of manifesting the effect depends on the radiation dose, including carcinogenesis and induction of heritable defects; (2) psychological, especially following accidental exposures; and (3) tissue reactions, occurring when sufficient cells are killed after exposure to radiation doses above a certain threshold, including the acute radiation syndrome (radiation sickness) and radiation burns.
Injuries, envenoming, poisoning, and allergic reactions caused by animals
Authors: Warrell David A. 
Published: February 2020

Abstract
Attacks by wild and domesticated animals are increasing worldwide. They are best prevented by taking local advice about minimizing exposure. Injuries usually occur in places remote from medical care. They may involve extensive trauma, haemorrhagic shock, and a high risk of bacterial contamination. First aid consists of resuscitation, control of bleeding and perforating injuries, intravenous fluid replacement, and rapid evacuation to hospital for emergency surgery and treatment of infection. In hospital, specific antivenom (hyperimmune equine or ovine immunoglobulins) is given if there is evidence of systemic or severe local envenoming. Early anaphylactic or pyrogenic reactions and late serum sickness antivenom reactions are common but not predictable by hypersensitivity tests.
Poisonous fungi
Authors: Persson Hans , Warrell David A. 
Published: February 2020

Abstract
This chapter covers poisoning by members of the fungal subkingdom Dikarya that includes most of the ‘higher fungi’. The phylum Ascomycota contains the medically important toxic fungi Claviceps purpurea, the cause of ergotism, Aspergillus flavus, a source of hepatotoxic and carcinogenic aflatoxins, the edible but potentially toxic morel mushrooms (Morchella species), Gyromitra species, and Podostroma cornudamae that has caused multisystem symptoms and signs. The phylum Basidiomycota includes the order Agaricales (gilled mushrooms/toadstools or agarics) to which most of the medically important larger fungi belong. ‘Mushroom’ and ‘toadstool’ may suggest ‘edible’ and ‘poisonous’ respectively, but these terms are not strictly applied. Poisonous species must be distinguished from field (Agaricus campestris) and cultivated (A. bisporus) mushrooms and from the many other mushrooms that are considered to be delicious and are passionately sought after by mycophiles worldwide.
Nutrition: Macronutrient metabolism
Authors: Frayn Keith N. , Evans Rhys D. 
Published: February 2020

Abstract
Food intake is sporadic and, in many cultures, occurs in three daily boluses. At the same time, energy expenditure is continuous and can vary to a large extent independently of the pattern of energy intake, although fixed or predictable demands (e.g. through occupation) means that in most persons food intake and energy expenditure are soon balanced. The body has developed complex systems that direct excess nutrients into storage pools; as they are needed, they also regulate the mobilization of nutrients from these pools. Carbohydrate, lipid, and protein (the latter a source of amino acids) are the three types of energy supply that are stored variably and assimilated from food each day. That we can carry on our daily lives without thinking about whether to store or mobilize fuels, and which to use, attests to the remarkable efficiency and refinement of these systems of metabolic control.