Wheat yellow rust ("Puccinia striiformis" f.sp. "tritici"), also known as stripe rust, is one of the three wheat rust diseases principally found in wheat grown in cooler environments. Such locations are generally associated with northern latitudes or cooler seasons.

As R.P. Singh, J. Huerta-Espino, and A.P. Roelfs say in their (undated) comprehensive review of literature on the wheat rusts for UN FAO:

"Although Gadd first described stripe rust of wheat in 1777, it was not until 1896 that Eriksson and Henning (1896) showed that stripe rust resulted from a separate pathogen, which they named P. glumarum. In 1953, Hylander et al. (1953) revived the name P. striiformis."

Leaf rust is a fungal disease of barley caused by "Puccinia hordei". It is also known as brown rust and it is the most important rust disease on barley.

Velvet disease (also called gold-dust, rust and coral disease) is a fish disease caused by dinoflagellate parasites of the genus "Piscinoodinium", specifically "Amyloodinium" in marine fish, and "Oodinium" in freshwater fish. The disease gives infected organisms a dusty, brownish-gold color. The disease occurs most commonly in tropical fish, and to a lesser extent, marine aquaria.

The single-celled parasite's life cycle can be divided into three major phases. First, as a tomont, the parasite rests at the water's floor and divides into as many as 256 tomites. Second, these juvenile, motile tomites swim about in search of a fish host, meanwhile using photosynthesis to grow, and to fuel their search. Finally, the adolescent tomite finds and enters the slime coat of a host fish, dissolving and consuming the host's cells, and needing only three days to reach full maturity before detaching to become a tomont once more.

Pustules of leaf rust are small and circular, producing a mass of orange-brown powdery spores. They appear on the leaf sheaths and predominantly on the upper leaf surfaces. Heavily infected leaves die prematurely.

Citrus Black Spot is a fungal disease caused by Guignardia citricarpa. This Ascomycete fungus affects citrus plants throughout subtropical climates, causing a reduction in both fruit quantity and quality. Symptoms include both fruit and leaf lesions, the latter being critical to inter-tree dispersal. Strict regulation and management is necessary to control this disease since there are currently no citrus varieties that are resistant.

False melanose lesions are characterized by many small, tan, slightly raised lesions. The lesions are much smaller than the hard spot variety with an average diameter of less than 1 mm (.04 in).

They are found on unripe fruit and are difficult to observe later in the season. Unlike hard spot lesions, no pycnidia are present.

The lesions are most frequent on the lower limbs, but may occur anywhere on the body, including the hands, arms, torso and even the neck. They may vary in number and erupt in mass numbers.

They consist of irregular patches of orange or brown pigmentation with characteristic "cayenne pepper" spots appearing within and at the edge of old lesions.

There are usually no symptoms, although there may be some slight itching, but there is no pain.

The eruption may persist for many years. The pattern of the eruption changes, with slow extension and often some clearing of the original lesions.

Schamberg's disease, or progressive pigmented purpuric dermatitis, is a chronic discoloration of the skin which usually affects the legs and often spreads slowly. This disease is more common in males and may occur at any age from childhood onward. This condition is observed worldwide and has nothing to do with race or ethnic background.

Although many people with a defective AMPD gene are asymptomatic, others may have symptoms such as exercise intolerance, muscle pain, and muscle cramping.

- Fatigue

- MADD lowers aerobic power output, so increased anaerobic power is needed to perform the same amount of work.

- Without myoadenlyate deaminase, heavy activity causes adenosine to be released into the cell or perfused into the surrounding tissues. Fatigue and sedation after heavy exertion can be caused by excess adenosine in the cells which signals muscle fiber to feel fatigued. In the brain, excess adenosine decreases alertness and causes sleepiness. In this way, adenosine may play a role in fatigue from MADD.

- Recovery from over-exertion can be hours, days or even months. In cases of rhabdomyolysis, which is the rapid breakdown of muscle fibers, time to recovery is dependent on duration and intensity of original activity plus any excess activity during the recovery period.

- Muscle pain

- Muscle pain from MADD is not well understood, but is partially due to high levels of lactate. Increased levels of free adenosine temporarily decrease pain, allowing over-exertion without awareness. The over exertion can cause mild to severe cases of rhabdomyolysis, which is painful.

- Adenosine mediates pain through adenosine receptors. MADD causes an increase of free adenosine during heavy activity which may cause exercise-induced muscle pain. Over time, excess free adenosine down-regulates primary A1 adenosine receptors, leading to increased muscle pain. Secondary receptors (A3) increase peripheral inflammation, which also increases pain.

- Muscle cramping

- The cause of cramping is unknown, but may be related to elevated lactate, increased calcium signaling across the sarcoplasmic reticulum caused by membrane instability from reduced levels of ATP, or increased levels of free adenosine.

- Muscle weakness

- Muscle weakness is not a major symptom, though the progressive effects of chronic muscle damage from rhabdomyolysis will eventually cause significant weakness. Similarly, the long-term metabolic effects may result in nerve damage.

The muscle weakness of botulism characteristically starts in the muscles supplied by the cranial nerves—a group of twelve nerves that control eye movements, the facial muscles and the muscles controlling chewing and swallowing. Double vision, drooping of both eyelids, loss of facial expression and swallowing problems may therefore occur. In addition to affecting the voluntary muscles, it can also cause disruptions in the autonomic nervous system. This is experienced as a dry mouth and throat (due to decreased production of saliva), postural hypotension (decreased blood pressure on standing, with resultant lightheadedness and risk of blackouts), and eventually constipation (due to decreased forward movement of intestinal contents). Some of the toxins (B and E) also precipitate nausea, vomiting, and difficulty with talking. The weakness then spreads to the arms (starting in the shoulders and proceeding to the forearms) and legs (again from the thighs down to the feet).

Severe botulism leads to reduced movement of the muscles of respiration, and hence problems with gas exchange. This may be experienced as dyspnea (difficulty breathing), but when severe can lead to respiratory failure, due to the buildup of unexhaled carbon dioxide and its resultant depressant effect on the brain. This may lead to respiratory compromise and death if untreated.

Clinicians frequently think of the symptoms of botulism in terms of a classic triad: bulbar palsy and descending paralysis, lack of fever, and clear senses and mental status ("clear sensorium").

Adenosine monophosphate deaminase deficiency type 1, also called myoadenylate deaminase deficiency (MADD), is a recessive genetic metabolic disorder that affects approximately 1–2% of populations of European descent. It appears to be considerably rarer in Asian populations. The genetic form is caused by a defect in the gene for AMP deaminase though there is also an acquired form of AMP deficiency.

Botulism is a rare and potentially fatal illness caused by a toxin produced by the bacterium "Clostridium botulinum". The disease begins with weakness, blurred vision, feeling tired, and trouble speaking. This may then be followed by weakness of the arms, chest muscles, and legs. The disease does not usually affect consciousness or cause a fever.

Botulism can be spread in several different ways. The bacterial spores which cause it are common in both soil and water. They produce the botulinum toxin when exposed to low oxygen levels and certain temperatures. Foodborne botulism happens when food containing the toxin is eaten. Infant botulism happens when the bacteria develops in the intestines and releases the toxin. This typically only occurs in children less than six months old, as protective mechanisms develop after that time. Wound botulism is found most often among those who inject street drugs. In this situation, spores enter a wound, and in the absence of oxygen, release the toxin. It is not passed directly between people. The diagnosis is confirmed by finding the toxin or bacteria in the person in question.

Prevention is primarily by proper food preparation. The toxin, though not the organism, is destroyed by heating it to more than for longer than 5 minutes. Honey can contain the organism, and for this reason, honey should not be fed to children under 12 months. Treatment is with an antitoxin. In those who lose their ability to breathe on their own, mechanical ventilation may be necessary for months. Antibiotics may be used for wound botulism. Death occurs in 5 to 10% of people. Botulism also affects many other animals. The word is from Latin, "botulus", meaning sausage. Early descriptions of botulism date from at least as far back as 1793 in Germany.

Schamberg's disease, (also known as "progressive pigmentary dermatosis of Schamberg", "purpura pigmentosa progressiva" (PPP), and "Schamberg's purpura") is a chronic discoloration of the skin found in people of all ages, usually affecting the legs. It slowly spreads throughout the body, and is most common in males. It is named after Jay Frank Schamberg, who described it in 1901. There is no known cure for this disease and it is not a life-threatening condition. The skin lesions may cause itching, which can be treated by applying cortisone cream. The cortisone cream will only help with the itching and the discoloration of the skin will remain, which may cause a cosmetic concern in the future. Schamberg's disease is usually asymptomatic meaning that it shows no signs of this condition, except for the discoloration of the skin. This condition is caused by leaky blood vessels, where red blood cells escape near the surface of skin and release its iron into the surrounding tissue. The cause of the leaky capillaries is unknown.

Tetanus often begins with mild spasms in the jaw muscles—also known as lockjaw or trismus. The spasms can also affect the facial muscles resulting in an appearance called risus sardonicus. Chest, neck, back, abdominal muscles, and buttocks may be affected. Back muscle spasms often cause arching, called opisthotonos. Sometimes the spasms affect muscles that help with breathing, which can lead to breathing problems.

Prolonged muscular action causes sudden, powerful, and painful contractions of muscle groups, which is called "tetany". These episodes can cause fractures and muscle tears. Other symptoms include drooling, excessive sweating, fever, hand or foot spasms, irritability, difficulty swallowing, suffocation, heart attack, breathing problems, irregular heartbeat, and uncontrolled urination or defecation.

Even with treatment, about 10% of people who contract tetanus die. The mortality rate is higher in unvaccinated people and people over 60 years of age.

Generalized tetanus is the most common type of tetanus, representing about 80% of cases. The generalized form usually presents with a descending pattern. The first sign is trismus, or lockjaw, and the facial spasms called risus sardonicus, followed by stiffness of the neck, difficulty in swallowing, and rigidity of pectoral and calf muscles. Other symptoms include elevated temperature, sweating, elevated blood pressure, and episodic rapid heart rate. Spasms may occur frequently and last for several minutes with the body shaped into a characteristic form called opisthotonos. Spasms continue for up to four weeks, and complete recovery may take months.

Sympathetic overactivity (SOA) is common in severe tetanus and manifests as labile hypertension, tachycardia, dysrhythmia, peripheral vasculature constriction, profuse sweating, fever, increased carbon dioxide output, increased catecholamine excretion and late development of hypotension.

Death can occur within four days.

Gougerot–Blum syndrome (also known as "pigmented purpuric lichenoid dermatitis", and "pigmented purpuric lichenoid dermatitis of Gougerot and Blum") is a variant of pigmented purpuric dermatitis, a skin condition characterized by minute, rust-colored to violaceous, lichenoid papules that tend to fuse into plaques of various hues. Relative to other variants, it is characterized clinically by a male predominance, pruritus, with a predilection for the legs, and histologically, it features a densely cellular lichenoid infiltrate.

It was characterized in 1925.

Gougerot–Blum syndrome is named after the French dermatologists Henri Gougerot (1881–1955) and Paul Blum (1878–1933).

Lichen aureus (also known as "lichen purpuricus") is a skin condition characterized by the sudden appearance of one or several golden or rust-colored, closely packed macules or lichenoid papules.

Malnutrition is a condition that results from eating a diet in which nutrients are either not enough or are too much such that the diet causes health problems. It may involve calories, protein, carbohydrates, vitamins or minerals. Not enough nutrients is called undernutrition or undernourishment while too much is called overnutrition. Malnutrition is often used to specifically refer to undernutrition where an individual is not getting enough calories, protein, or micronutrients. If undernutrition occurs during pregnancy, or before two years of age, it may result in permanent problems with physical and mental development. Extreme undernourishment, known as starvation, may have symptoms that include: a short height, thin body, very poor energy levels, and swollen legs and abdomen. People also often get infections and are frequently cold. The symptoms of micronutrient deficiencies depend on the micronutrient that is lacking.

Undernourishment is most often due to not enough high-quality food being available to eat. This is often related to high food prices and poverty. A lack of breastfeeding may contribute, as may a number of infectious diseases such as: gastroenteritis, pneumonia, malaria, and measles, which increase nutrient requirements. There are two main types of undernutrition: protein-energy malnutrition and dietary deficiencies. Protein-energy malnutrition has two severe forms: marasmus (a lack of protein and calories) and kwashiorkor (a lack of just protein). Common micronutrient deficiencies include: a lack of iron, iodine, and vitamin A. During pregnancy, due to the body's increased need, deficiencies may become more common. In some developing countries, overnutrition in the form of obesity is beginning to present within the same communities as undernutrition. Other causes of malnutrition include anorexia nervosa and bariatric surgery.

Efforts to improve nutrition are some of the most effective forms of development aid. Breastfeeding can reduce rates of malnutrition and death in children, and efforts to promote the practice increase the rates of breastfeeding. In young children, providing food (in addition to breastmilk) between six months and two years of age improves outcomes. There is also good evidence supporting the supplementation of a number of micronutrients to women during pregnancy and among young children in the developing world. To get food to people who need it most, both delivering food and providing money so people can buy food within local markets are effective. Simply feeding students at school is insufficient. Management of severe malnutrition within the person's home with ready-to-use therapeutic foods is possible much of the time. In those who have severe malnutrition complicated by other health problems, treatment in a hospital setting is recommended. This often involves managing low blood sugar and body temperature, addressing dehydration, and gradual feeding. Routine antibiotics are usually recommended due to the high risk of infection. Longer-term measures include: improving agricultural practices, reducing poverty, improving sanitation, and the empowerment of women.

There were 793 million undernourished people in the world in 2015 (13% of the total population). This is a reduction of 216 million people since 1990 when 23% were undernourished. In 2012 it was estimated that another billion people had a lack of vitamins and minerals. In 2015, protein-energy malnutrition was estimated to have resulted in 323,000 deaths—down from 510,000 deaths in 1990. Other nutritional deficiencies, which include iodine deficiency and iron deficiency anemia, result in another 83,000 deaths. In 2010, malnutrition was the cause of 1.4% of all disability adjusted life years. About a third of deaths in children are believed to be due to undernutrition, although the deaths are rarely labelled as such. In 2010, it was estimated to have contributed to about 1.5 million deaths in women and children, though some estimate the number may be greater than 3 million. An additional 165 million children were estimated to have stunted growth from malnutrition in 2013. Undernutrition is more common in developing countries. Certain groups have higher rates of undernutrition, including women—in particular while pregnant or breastfeeding—children under five years of age, and the elderly. In the elderly, undernutrition becomes more common due to physical, psychological, and social factors.

Kwashiorkor is mainly caused by inadequate protein intake. The main symptoms are edema, wasting, liver enlargement, hypoalbuminaemia, steatosis, and possibly depigmentation of skin and hair. Kwashiorkor is further identified by swelling of the belly, which is deceiving of actual nutritional status. The term means ‘displaced child’ and is derived from a Ghana language of West Africa, means "the sickness the older one gets when the next baby is born," as this is when the older child is deprived of breast feeding and weaned to a diet composed largely of carbohydrates.

Conditions which commonly involve hemoptysis include bronchitis and pneumonia, lung cancers and tuberculosis. Other possible underlying causes include aspergilloma, bronchiectasis, coccidioidomycosis, pulmonary embolism, pneumonic plague, and cystic fibrosis. Rarer causes include hereditary hemorrhagic telangiectasia (HHT or Rendu-Osler-Weber syndrome), Goodpasture's syndrome, and granulomatosis with polyangiitis. In children, hemoptysis is commonly caused by the presence of a foreign body in the airway. The condition can also result from over-anticoagulation from treatment by drugs such as warfarin.

Blood-laced mucus from the sinus or nose area can sometimes be misidentified as symptomatic of hemoptysis (such secretions can be a sign of nasal or sinus cancer, but also a sinus infection). Extensive non-respiratory injury can also cause one to cough up blood. Cardiac causes like congestive heart failure and mitral stenosis should be ruled out.

The origin of blood can be identified by observing its color. Bright-red, foamy blood comes from the respiratory tract, whereas dark-red, coffee-colored blood comes from the gastrointestinal tract. Sometimes hemoptysis may be rust-colored.

The most common cause of minor hemoptysis is bronchitis.

- Lung cancer, including both non-small cell lung carcinoma and small cell lung carcinoma.

- Sarcoidosis

- Aspergilloma

- Tuberculosis

- Histoplasmosis

- Pneumonia

- Pulmonary edema

- Pulmonary embolism

- Foreign body aspiration and aspiration pneumonia

- Goodpasture's syndrome

- Granulomatosis with polyangiitis

- Eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome)

- Bronchitis

- Bronchiectasis

- Pulmonary embolism

- Anticoagulant use

- Trauma

- Lung abscess

- Mitral stenosis

- Tropical eosinophilia

- Bleeding disorders

- Hughes-Stovin Syndrome and other variants of Behçet's disease

- Squamous Cell Carcinoma Of Esophagus

Hemoptysis is the coughing up of blood or blood-stained mucus from the bronchi, larynx, trachea, or lungs. This can occur with lung cancer, infections such as tuberculosis, bronchitis, or pneumonia, and certain cardiovascular conditions. Hemoptysis is considered massive at . In such cases, there are always severe injuries. The primary danger comes from choking, rather than blood loss.