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Acute poisoning?, Acute pesticide poisoning?, Organophosphates/carbamates?, Acute poisoning with pharmaceuticals/chemicals?, Mushroom poisoning?, Methanol poisoning?, Fish and shellfish poisoning?, Snake bite?, Scorpion sting?, Spider bite?, Fish stings?, Jelly fish stings?

Differential diagnosis of fevers?, Fever without localizing features?, Sepsis?, Cancer?, General rules of cancer management?, Rheumatoid arthritis?, Osteoarthritis?, Systemic lupus erythematosus?, Typhoid and paratyphoid fevers?, Rickettsioses?, Bartonella?, Ehrlichia?, Coxiella?, Relapsing fevers?, Leptospirosis?, Brucellosis?, Plague?, Melioidosis?, Anthrax?, African trypanosomiasis?, American trypanosomiasis?, Visceral leishmaniasis (kala-azar)?, Infectious mononucleosis?, Measles?, Arboviruses and zoonotic haemorrhagic fever viruses , Ebola and Marburg virus diseases, Crimean-Congo haemorrhagic fever, Rift Valley fever, Lassa fever, Hantavirus infections, Severe fever and thrombocytopenia, Zika virus, Japanese encephalitis , Dengue virus, Yellow fever, West Nile virus , Kyasanur Forest Disease, Chikungunya, Ross River fever, O'nyong nyong

Human pathogens are found in six genera of Reoviridae: Reovirus, Rotavirus, Orthoreovirus, and three arthropod-borne genera: Coltivirus (Colorado tick fever, Salmon River virus, and Eyach viruses); Orbivirus (Kemerovo, Changuinola, Orungo, and Lebombo); and Seadornavirus (Banna virus). Colorado tick fever is common in parts of north-western North America; acquired from tick (ixodid) bites, most often by hikers and campers, presenting 3–6 days later with sudden fever, rigors, generalized aches, myalgia, headache and backache, rashes (12%), and gastrointestinal symptoms (20%). Diagnosis is confirmed by detection of viral antigen in erythrocytes or serum, or by serodiagnosis. Management is symptomatic. Illness usually resolves in 10–14 days, but convalescence may be prolonged. Prevention is by avoiding, repelling, and rapidly removing ticks; no vaccines are available.

Molluscum contagiosum is caused by a Molluscipox DNA virus which infects keratinocytes of the epidermal stratum spinosum, producing distinctive small umbilicated papules on the skin. Its genome encodes a variety of proteins that suppress the host’s immune response. In children it is spread by skin contact, producing few or many lesions, while in sexually active adults it causes anogenital lesions. Molluscum is self-limiting within a few years in the immunocompetent, but those with pre-existing atopic eczema and immunosuppression, notably AIDS, commonly develop persistent diffuse eruptions with larger papules. Lesions can be removed mechanically or chemically. More severe infections can be treated with imiquimod or cidofovir.

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.

The Rhabdoviridae are a large family of RNA viruses, two genera of which infect animals: the genus Lyssavirus contains rabies and rabies-related viruses that cause at least 55,000 deaths annually in Asia and Africa. The risks and problems posed by rabies and other lyssaviruses vary across the world. Viruses can penetrate broken skin and intact mucosae. Humans are usually infected when virus-laden saliva is inoculated through the skin by the bite of a rabid animal, usually a dog. Although the greatest threat to man is the persistent cycle of infection in stray dogs, several other terrestrial mammal species are reservoirs of infection. In the Americas, bat viruses and also classic type 1 rabies and insectivorous bats have become the principal vectors of infection to humans in the United States of America. Elsewhere in the world, there is increasing evidence of widespread rabies-related lyssavirus infection of bats.

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).

This chapter looks at how enteroviruses are responsible for most cases of viral meningitis where a pathogen is identified; many other viruses can also cause meningitis with considerable geographical and seasonal variation. Their typical presentation is with sudden onset of fever, headache, neck stiffness, and photophobia. There is no change in conscious level. Prognosis is generally good, though recent data suggest not always. Viruses invade and damage the central nervous system in two ways: directly, by infecting the leptomeninges, brain, and spinal cord; and, indirectly, by inducing an immunological reaction resulting in para and postinfectious diseases. In both cases, the terms ‘meningitis’, ‘encephalitis’, and ‘myelitis’ are used alone or in combination.

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.

This chapter covers orf and milker’s nodule, which are characteristic nodular skin lesions caused by parapox viruses of sheep and goats, or cattle, respectively. These viruses are epitheliotropic and able to suppress the host’s immune response. The infections are occupational zoonoses of people working with ruminants. A single or small number of somewhat painful pustules develops, usually on the hand, at the site of contact with an animal’s lesions. Fever is unusual, but local lymphadenopathy, erythema multiforme, or secondary infection may occur. Spontaneous resolution within 6 weeks is usual. Multiple, giant lesions may develop in the immunosuppressed. Topical cidofovir is effective in severe cases.