Ascochyta blights occur throughout the world and can be of significant economic importance. Three fungi contribute to the ascochyta blight disease complex of pea ("Pisum sativum"). "Ascochyta pinodes" (sexual stage: "Mycosphaerella pinodes") causes Mycosphaerella blight. "Ascochyta pinodella" (synonym: "Phoma medicaginis" var. "pinodella") causes Ascochyta foot rot, and "Ascochyta pisi" causes Ascochyta blight and pod spot. Of the three fungi, "Ascochyta pinodes" is of the most importance. These diseases are conducive under wet and humid conditions and can cause a yield loss of up to fifty percent if left uncontrolled. The best method to control ascochyta blights of pea is to reduce the amount of primary inoculum through sanitation, crop-rotation, and altering the sowing date. Other methods—chemical control, biological control, and development of resistant varieties—may also be used to effectively control ascochyta diseases.

"Verticillium" wilt begins as a mild, local infection, which over a few years will grow in strength as more virile strains of the fungus develop. If left unchecked the disease will become so widespread that the crop will need to be replaced with resistant varieties, or a new crop will need to be planted altogether.

Control of "Verticilium" can be achieved by planting disease free plants in uncontaminated soil, planting resistant varieties, and refraining from planting susceptible crops in areas that have been used repeatedly for solanaceous crops. Soil fumigation can also be used, but is generally too expensive over large areas.

In tomato plants, the presence of ethylene during the initial stages of infection inhibits disease development, while in later stages of disease development the same hormone will cause greater wilt. Tomato plants are available that have been engineered with resistant genes that will tolerate the fungus while showing significantly lower signs of wilting.

"Verticillium albo-altrum", "Verticilium dahliae" and "V. longisporum" can overwinter as melanized mycelium or microsclerotia within live vegetation or plant debris. As a result, it can be important to clear plant debris to lower the spread of disease. "Verticilium dahliae" and "V. longisporum" are able to survive as microsclerotia in soil for up to 15 years.

Susceptible tomato seedlings inoculated with arbuscular mycorrhizal fungi and "Trichoderma Harzianum" show increased resistance towards "Verticillium" wilt.

Because "O. sericea" is both frequently encountered and relatively palatable to livestock, it is an important cause of economic losses in livestock production. Keeping livestock away from locoweed infested pasture in spring and fall when grass and other forbs are not actively growing is recommended. Another suggested remedy is to provide palatable supplemental nutrients if animals are to be kept in infested pasture. These remedies take into account livestock preference for locoweed during seasons when grass is dry and not very nutritious. Conditioned food aversion has been used experimentally to discourage livestock from eating it. In horses, a small study has shown promising results using lithium chloride as the aversive agent.

Verticillium wilt is a wilt disease of over 350 species of eudicot plants caused by six species of Verticillium genus, "V. dahliae", "V. albo-atrum", "V. longisporum", V. nubilum, V. theobromae and

V. tricorpus. (See, for example, Barbara, D.J. & Clewes, E. (2003). "Plant pathogenic Verticillium species: how many of them are there?" Molecular Plant Pathology 4(4).297-305. Blackwell Publishing.) Many economically important plants are susceptible including cotton, tomatoes, potatoes, oilseed rape, eggplants, peppers and ornamentals, as well as others in natural vegetation communities. Many eudicot species and cultivars are resistant to the disease and all monocots, gymnosperms and ferns are immune.

Symptoms are superficially similar to "Fusarium" wilts. There is no chemical control for the disease but crop rotation, the use of resistant varieties and deep plowing may be useful in reducing the spread and impact of the disease.

Certain techniques can be used to determine which pathogen is causing disease. One standard technique for distinguishing strains is microscopy. Under a microscope, "M. pinodes" can be diagnosed by the presence of pseudothecia. "P pinodella" can be diagnosed by the size of conidia produced. "P. pinodella" produces conidia that are smaller than the conidia of "M. pinodes" or "A. pisi". "A. pisi" can be diagnosed by the color of the conidia. In comparison to the light colored, buff spore masses of "M. pinodes" and "P. pinodella" produced on oatmeal agar, "A. pisi" spores masses are carrot red.

Other techniques for diagnosis involve serological assays, isoenzyme analysis, restriction fragment length polymorphisms (RFLPs), random amplified polymorphic DNA (RAPD) assays, and by using monoclonal antibodies.

Locoweed (also crazyweed and loco) is a common name in North America for any plant that produces swainsonine, a phytotoxin harmful to livestock. Worldwide, swainsonine is produced by a small number of species, most in three genera of the flowering plant family Fabaceae: "Oxytropis" and "Astragalus" in North America, and "Swainsona" in Australia. The term locoweed usually refers only to the North American species of "Oxytropis" and "Astragalus", but this article includes the other species as well. Some references may list "Datura stramonium" as locoweed.

Locoweed is relatively palatable to livestock, and some individual animals will seek it out. Livestock poisoned by chronic ingestion of large amounts of swainsonine develop a medical condition known as locoism (also swainsonine disease, swainsonine toxicosis, locoweed disease, and loco disease; North America) and pea struck (Australia). Locoism is reported most often in cattle, sheep, and horses, but has been reported also in elk and deer. It is the most widespread poisonous plant problem in the western United States. Agricultural Research Service and New Mexico State University scientists have been collaborating since 1990 to help solve the problem that locoweed presents to livestock farmers. The research involved identifying the fungal species that produces the locoweed toxins, pinpointing levels of toxicity in animals once they have ingested locoweed, observing the effects of locoweed toxins on livestock’s reproduction and grazing preferences, etc. Together, the scientists assembled a grazing management scheme to help farmers avoid the poisonous locoweed.

Most of the 2000 species of "Astragalus", including many that are commonly known as locoweeds, do not produce swainsonine. Some species, including a few that produce swainsonine, accumulate selenium. This has led to confusion between swainsonine poisoning and selenium poisoning due to this genus.

Coral diseases, comprising the diseases that affect corals, injure the living tissues and often result in the death of part or the whole of the colony. These diseases have been occurring more frequently in the twenty-first century as conditions become more stressful for many shallow-water corals. The pathogens causing the diseases include bacteria, fungi and protozoa, but it is not always possible to identify the pathogen involved.

Grapevine trunk diseases (GTD) are the most destructive diseases of vineyards worldwide. Fungicides (such as sodium arsenite or 8-hydroxyquinoline, used to fight esca) with the potential to control GTD have been banned in Europe and there are no highly effective treatments available. Action to develop new strategies to fight these diseases are needed.

The following fungal species are responsible for grapevine trunk diseases:

- "Botryosphaeria dothidea" and other "Botryosphaeria" species, such as , "B. obtusa", "B. parva" and "B. australis",

- "Cylindrocarpon" spp., "Ilyonectria" spp., "Dactylonectria" spp. and "Campylocarpon" spp.(cause of black foot disease)

- "Diplodia seriata" (cause of bot canker)

- "Diplodia mutila" (cause of Botryosphaeria dieback)

- "Dothiorella iberica"

- "Dothiorella viticola"

- "Eutypa lata" (cause of Eutypa dieback)

- "Fomitiporia mediterranea" (cause of esca)

- "Lasiodiplodia theobromae" (cause of Botryosphaeria dieback)

- "Neofusicoccum australe"

- "Neofusicoccum luteum"

- "Neofusicoccom parvum"

- "Phaeoacremonium minimum" (cause of esca and Petri disease) and other "Phaeoacremonium" species

- "Phaeomoniella chlamydospora" (cause of esca and Petri disease)

Corals growing in the Caribbean Sea are particularly affected by disease, perhaps because of the limited water circulation and the density of the human population on the surrounding land masses. Disease is also present in the tropical Indo-Pacific, but it is not so widespread, perhaps because of the more dispersed locations of the reefs.

Up until the advent of modern therapies, favid was widespread worldwide; prior to Schönlein's recognition of it as a fungal disease, it was frequently confused with Hansen's disease, better known as leprosy, and European sufferers were sometimes committed to leprosaria. Today, due to this species' high susceptibility to the antifungal drug griseofulvin, it has been eliminated from most parts of the world except rural central Asia and scattered rural areas of Africa. It is mainly a disease connected to demographic poverty and isolation, but is so readily treatable that it is among the diseases most likely to be completely eliminated by modern medicine.

Osteolathyrism is a collagen cross-linking deficiency brought on by dietary over-reliance on the seeds of "Lathyrus sativus" or grass pea, a legume often grown as a famine crop in Asia and East Africa. Other members of the genus are also known to cause the disease, including "L. sylvestris", "L. cicera", and "L. clymenum". "L. sativus" grows well under famine conditions, often severe drought, where it is cultivated. The condition results in damage to bone and mesenchymal connective tissues. It is seen in people in combination with neurolathyrism and angiolathyrism in areas where famine demands reliance on a crop with known detrimental effects. It occurs in cattle and horses with diets overreliant upon the grass pea. Osteolathyrism is caused by a variety of osteolathyrogenic compounds, specifically excitatory amino-compounds. The most widely-studied of these compounds is beta-aminopropionitrile (BAPN), which exerts its deleterious effect by an unknown yet potently irreversible mechanism. Other instigators are ureides, semicarbazides and thiosemicarbazides, which are believed to chelate the prosthetic Cu(II)-bipyridine cofactor complex in the enzyme lysyl oxidase.

It was the first disease in which a fungus was discovered by J. L. Schönlein in 1839; the discovery was published in a brief note of twenty lines in Millers Archive for that year (p. 82), the fungus having been subsequently named by Robert Remak; "Achorion schoenleinii" after its discoverer.

In 1892, two additional "species" of the fungus were described by Paul Gerson Unna, the "Favus griseus", giving rise to greyish-yellow scutula, and the "Favus sulphureus celerior", causing sulfur-yellow scutula of a rapid growth. This was in the days before scientists learned to rigorously distinguish microorganism identities from disease identities, and these antique, ambiguous disease-based names no longer have status either in mycology or in dermatology.

Similar looking infections, sometimes diagnosed as favid but more often as atypical inflammatory tinea, may rarely be produced by agents of more common dermatophyte fungal infections, in particular "Microsporum gypseum", the most common soil-borne dermatophyte fungus, and "Trichophyton mentagrophytes" (name used in post-1999 sense for a phylogenetic species formerly referred to as "Trichophyton mentagrophytes" var. "quinckeanum"), the agent of favid infection of the mouse.

A boil may clear up on its own without bursting, but more often it will need to be opened and drained. This will usually happen spontaneously within two weeks. Regular application of a warm moist compress, both before and after a boil opens, can help speed healing. The area must be kept clean, hands washed after touching it, and any dressings disposed of carefully, in order to avoid spreading the bacteria. A doctor may cut open or "lance" a boil to allow it to drain, but squeezing or cutting should not be attempted at home, as this may further spread the infection. Antibiotic therapy may be recommended for large or recurrent boils or those that occur in sensitive areas (such as the groin, breasts, armpits, around or in the nostrils, or in the ear). Antibiotics should not be used for longer than one month, with at least two months (preferably longer) between uses, otherwise it will lose its effectiveness. If the patient has chronic (more than two years) boils, removal by plastic surgery may be indicated.

Furuncles at risk of leading to serious complications should be incised and drained if antibiotics or steroid injections are not effective. These include furuncles that are unusually large, last longer than two weeks, or occur in the middle of the face or near the spine. Fever and chills are signs of sepsis and indicate immediate treatment is needed.

Staphylococcus aureus has the ability to acquire antimicrobial resistance easily, making treatment difficult. Knowledge of the antimicrobial resistance of "S. aureus" is important in the selection of antimicrobials for treatment.

The treatment of choice by dermatologists is a safe and inexpensive oral medication, griseofulvin, a secondary metabolite of the fungus "Penicillium griseofulvin". This compound is "fungistatic" (inhibiting the growth or reproduction of fungi) and works by affecting the microtubular system of fungi, interfering with the mitotic spindle and cytoplasmic microtubules. The recommended pediatric dosage is 10 mg/kg/day for 6–8 weeks, although this may be increased to 20 mg/kg/d for those infected by "T. tonsurans", or those who fail to respond to the initial 6 weeks of treatment. Unlike other fungal skin infections that may be treated with topical therapies like creams applied directly to the afflicted area, griseofulvin must be taken orally to be effective; this allows the drug to penetrate the hair shaft where the fungus lives. The effective therapy rate of this treatment is generally high, in the range of 88–100%.

Other oral antifungal treatments for tinea capitis also frequently reported in the literature include terbinafine, itraconazole, and fluconazole; these drugs have the advantage of shorter treatment durations than griseofulvin. However, concern has been raised about the possibility of rare side effects like liver toxicity or interactions with other drugs; furthermore, the newer drug treatments tend to be more expensive than griseofulvin.

On September 28, 2007, the U.S. Food and Drug Administration stated that Lamisil (Terbinafine hydrochloride, by Novartis AG) is a new treatment approved for use by children aged 4 years and older. The antifungal can be sprinkled on a child's food to treat the infection. Lamisil carries hepatotoxic risk, and can cause a metallic taste in the mouth.

Lysyl oxidase is an important enzyme for the creation of crosslinks between collagen triple-helices in connective tissue. By oxidizing the terminal amino group of lysine, an aldehyde is created. This aldehyde can undergo several reactions with neighboring aldehydes or amines to create strong covalent cross-links between collagen tertiary structures in bone and cartilage. The main product of these reactions is the aldimine compound dehydrohydroxylysinonorleucine. This unique crosslink can be formed by the Schiff base mechanism in which the lone pair of electrons on a primary amine react with the carbonyl carbon of an aldehyde. Other crosslinks include the formation of an α,β-unsaturated ketone via aldol condensation and hydroxylysinonorleucine.

If these crosslinks are not formed, as in the case of osteolathyrism, the synthesis of strong mesenchymal and mesodermal tissue is inhibited. Symptoms of osteolathyrism include weakness and fragility of connective tissue (i.e., skin, bones, and blood vessels (angiolathyrism) and the paralysis of the lower extremities associated with neurolathyrism. For these reasons, compounds containing lathyrogens should be avoided during pregnancy and growth of a child.

Tinea capitis caused by species of "Microsporum" and "Trichophyton" is a contagious disease that is endemic in many countries. Affecting primarily pre-pubertal children between 6 and 10 years, it is more common in males than females; rarely does the disease persist past age sixteen. Because spread is thought to occur through direct contact with afflicted individuals, large outbreaks have been known to occur in schools and other places where children are in close quarters; however, indirect spread through contamination with infected objects ("fomites") may also be a factor in the spread of infection. In the USA, tinea capitis is thought to occur in 3-8% of the pediatric population; up to one-third of households with contact with an infected person may harbor the disease without showing any symptoms.

The fungal species responsible for causing tinea capitis vary according to the geographical region, and may also change over time. For example, "Microsporum audouinii" was the predominant etiological agent in North America and Europe until the 1950s, but now "Trichophyton tonsurans" is more common in the USA, and becoming more common in Europe and the United Kingdom. This shift is thought to be due to the widespread use of griseofulvin, which is more effective against "M. audounii" than "T. tonsurans"; also, changes in immigration patterns and increases in international travel have likely spread "T. tonsurans" to new areas. Another fungal species that has increased in prevalence is "Trichophyton violaceum", especially in urban populations of the United Kingdom and Europe.

Recent research suggests that sulfur amino acids have a protective effect against the toxicity of ODAP.

Eating the chickling pea with grain having high concentrations of sulphur-based amino acids reduces the risk of lathyrism if grain is available. Food preparation is also an important factor. Toxic amino acids are readily soluble in water and can be leached. Bacterial (lactic acid) and fungal (tempeh) fermentation is useful to reduce ODAP content. Moist heat (boiling, steaming) denatures protease inhibitors which otherwise add to the toxic effect of raw grasspea through depletion of protective sulfur amino acids. During times of drought and famine, water for steeping and fuel for boiling is frequently also in short supply. Poor people sometimes know how to reduce the chance of developing lathyrism but face a choice between risking lathyrism or starvation.

The underlying cause for excessive consumption of grasspea is a lack of alternative food sources. This is a consequence of poverty and political conflict. The prevention of lathyrism is therefore a socio-economic challenge.

Other causes include poor immune system function such as from HIV/AIDS, diabetes, malnutrition, or alcoholism. Poor hygiene and obesity have also been linked. It may occur following antibiotic use due to the development of resistance to the antibiotics used. An associated skin disease favors recurrence. This may be attributed to the persistent colonization of abnormal skin with "S. aureus" strains, such as is the case in persons with atopic dermatitis.

Boils which recur under the arm, breast or in the groin area may be associated with hidradenitis suppurativa (HS).

A remedy, which can work within hours, perhaps by countering constipation, is to feed green pea to affected fish. Fish surgeons can also adjust the buoyancy of the fish by placing a stone in the swim bladder or performing a partial removal of the bladder.

The toxicological cause of the disease has been attributed to the neurotoxin ODAP which acts as a structural analogue of the neurotransmitter glutamate. Ingestion of legumes containing the toxin occurs, although knowledge of how to detoxify Lathyrus is present, but drought conditions can lead to fuel and water shortages preventing the necessary steps from being taken, particularly in impoverished countries. Lathyrism usually occurs where the despair of poverty and malnutrition leaves few other food options. Lathyrism can also be caused by food adulteration.

Fancy goldfish are among the fish most commonly affected by this disorder. The disease may be caused by intestinal parasites or by constipation induced by high nitrate levels from over feeding.

Surgical excision is required to treat a trichilemmal cyst. The method of treatment varies depending on the physician's training. Most physicians perform the procedure under local anesthetic. Others prefer a more conservative approach. This involves the use of a small punch biopsy about 1/4 the diameter of the cyst. The punch biopsy is used to enter the cyst cavity. The content of the cyst is emptied, leaving an empty sac. As the pilar cyst wall is the thickest and most durable of the many varieties of cysts, it can be grabbed with forceps and pulled out of the small incision. This method is best performed on cysts larger than a pea which have formed a thick enough wall to be easily identified after the sac is emptied. Small cysts have walls that are thin, and easily fragmented on traction. This increases the likelihood of cyst recurrence. This method often results in only a small scar, and very little if any bleeding.

Some ways to prevent airborne diseases include washing hands, using appropriate hand disinfection, getting regular immunizations against diseases believed to be locally present, wearing a respirator and limiting time spent in the presence of any patient likely to be a source of infection.

Exposure to a patient or animal with an airborne disease does not guarantee receiving the disease. Because of the changes in host immunity and how much the host was exposed to the particles in the air makes a difference to how the disease affects the body.

Antibiotics are not prescribed for patients to control viral infections. They may however be prescribed to a flu patient for instance, to control or prevent bacterial secondary infections. They also may be used in dealing with air-borne bacterial primary infections, such as pneumonic plague.

Additionally the Centers for Disease Control and Prevention (CDC) has told consumers about vaccination and following careful hygiene and sanitation protocols for airborne disease prevention. Consumers also have access to preventive measures like UV Air purification devices that FDA and EPA-certified laboratory test data has verified as effective in inactivating a broad array of airborne infectious diseases. Many public health specialists recommend social distancing to reduce the transmission of airborne infections.

Noxious gases can be categorized as : Simple asphyxiants, chemical asphyxiants, and irritant gases. The simple asphixiants are nitrogen, methane, and carbon dioxide.

The chemical asphyxiants are carbon monoxide, sulfuretted hydrogen and hydrogen cyanide.

The irritant gases are sulfur dioxide, ammonia, nitrogen dioxide, chlorine, phosgene, and fluorine and its compounds, which include luroine and hydrofluoric acid, fluorspar, fluorapatite, cryolite, and organic fluorine compounds.

Additionally, there are environmental diseases caused by the aromatic carbon compounds including : benzene, hexachlorocyclohexane, toluene diisocyanate, phenol, pentachlorophenol, quinone and hydroquinone.

Also included are the aromatic nitro-, amino-, and pyridilium-deratives: nitrobenzene, dinitrobenzene, trinitrotoluene, paramethylaminophenol sulfate (Metol), dinitro-ortho-cresol, aniline, trinitrophenylmethylnitramine (tetryl), hexanitrodiphenylamine (aurantia), phenylenediamines, and paraquat.

The aliphatic carbon compounds can also cause environmental disease. Included in these are methanol, nitroglycerine, nitrocellulose, dimethylnitrosamine, and the halogenated hydrocarbons: methyl chloride, methyl bromide, trichloroethylene, carbon tetrachloride, and the chlorinated naphthalenes. Also included are glycols: ethylene chlorhydrin and diethylene dioxide as well as carbon disulfide, acrylonitrile, acrylamide, and vinyl chloride.