Here is the list of the diseases beginning with letter “S“:
- Sandhoff disease
- Scarlet fever
- Sepsis / Septicemia
- Short bowel syndrome / Short gut
- Sickle-cell disease (SCD)
- Sjögren’s syndrome
- Spasmodic dysphonia
- Swine influenza
Salmonellosis is an infection with Salmonella bacteria. Most people infected with Salmonella develop diarrhea, fever, vomiting, and abdominal cramps 12 to 72 hours after infection. In most cases, the illness lasts 4 to 7 days and most people recover without treatment. However, in some cases the diarrhea may be so severe that the patient becomes dangerously dehydrated and must be taken to a hospital. At the hospital, the patient may receive intravenous fluids to treat the dehydration, and may be given medications to provide symptomatic relief, such as fever reduction. In severe cases, the Salmonella infection may spread from the intestines to the blood stream, and then to other body sites, and can cause death unless the person is treated promptly with antibiotics. The elderly, infants, and those with impaired immune systems are more likely to develop severe illness. Some people afflicted with salmonellosis later experience reactive arthritis, which can have long-lasting, disabling effects. There are different kinds of Salmonella, including Salmonella bongori and Salmonella enterica.
Sandhoff disease also known as Hexosaminidase A and B deficiency, is an autosomal recessive, genetic, lipid storage disorder. An autosomal recessive disease is one passed down from two carrier parents to their offspring. The disease causes a lysosomal storage disorder where the patient has the inability to create the beta-hexosaminidase A and beta-hexosaminidase B, which is an enzyme that leads to a build-up of GM2 gangliosides in tissues of the body. This build-up is toxic at high levels, which leads to a progressive destruction of the central nervous system, damages the tissues and eventually leads to death. There are three subsets of the disease based on when the patient shows symptoms: classic infantile, juvenile and adult late onset.
Sandhoff disease symptoms are clinically indeterminable from Tay-Sachs Disease. The classic infantile form of the disease has the most severe symptoms and is incredibly hard to diagnose at this early age. The first signs of symptoms begin before 6 months of age and the parents’ notice when the child begins digressing in their development. If the children had the ability to sit up by themselves or crawl they will lose this ability. This is caused by a slow deterioration of the muscles in the child’s body from the buildup of GM2 gangliosides. Since the body is unable to create the enzymes it needs within the central nervous system it is unable to attach to these gangliosides to break them apart and make them non-toxic. With this buildup there are several symptoms that begin to appear such as muscle/motor weakness, sharp reaction to loud noises, blindness, deafness, inability to react to stimulants, respiratory problems and infections, mental retardation, seizures, cherry red spots in the retina, enlarged liver and spleen (hepatosplenomegaly), pneumonia, or bronchopneumonia.
Currently Sandhoff disease does not have any standard treatment and does not have a cure. However, a person suffering from the disease needs proper nutrition, hydration, and maintenance of clear airways. To reduce some symptoms that may occur with Sandhoff disease, the patient may take anticonvulsants to manage seizures or medications to treat respiratory infections, and consume a precise diet consisting of puree foods due to difficulties swallowing. Infants with the disease usually die by the age of 3 due to respiratory infections. The patient must be under constant surveillance because they can suffer from aspiration or lack the ability to change from the passage way to their lungs versus their stomach and their spit travels to the lungs causing bronchopneumonia. The patient also lacks the ability to cough and therefore must undergo a treatment to shake up their body to remove the mucus from the lining of their lungs.
SAPHO syndrome includes a variety of inflammatory bone disorders that may be associated with skin changes. These diseases share some clinical, radiologic, and pathologic characteristics. An entity initially known as Chronic recurrent multifocal osteomyelitis (CRMO) was first described in 1972. Subsequently, in 1978, several cases of CRMO were associated with blisters on the palms and soles (palmoplantar pustulosis). Since then, a number of associations between skin conditions and osteoarticular disorders have been reported under a variety of names, including sternocostoclavicular hyperostosis, pustulotic arthro-osteitis, and acne-associated spondyloarthropathy. The term SAPHO was coined in 1987 to represent this spectrum of inflammatory bone disorders that may or may not be associated with dermatologic pathology.
Bisphosphonate therapy has been suggested as a first-line therapeutic option in many case reports and series. Treatment with tumor necrosis factor alpha antagonists (TNF inhibitors) have been tried in few patients with limited success. Other drugs which are used in psoriatic arthritis, to which SAPHO syndrome is closely related, have also been used in this condition. They include NSAIDs, corticosteroids, sulfasalazine, methotrexate, ciclosporin and leflunomide.
Some patients have responded to antibiotics. The rationale for their use is that Propionibacterium acnes, a bacterium known for its role in acne, has been isolated from bone biopsies of SAPHO patients.
Sarcoidosis, also called sarcoid, Besnier-Boeck disease or Besnier-Boeck-Schaumann disease, is a disease in which abnormal collections of chronic inflammatory cells (granulomas) form as nodules in multiple organs. The cause of sarcoidosis is unknown. Granulomas most often appear in the lungs or the lymph nodes, but virtually any organ can be affected. Normally the onset is gradual. Sarcoidosis may be asymptomatic or chronic. It commonly improves or clears up spontaneously. More than 2/3 of people with lung sarcoidosis have no symptoms after 9 years. About 50% have relapses. About 10% develop serious disability. Lung scarring or infection may lead to respiratory failure and death.
Between 30 and 70% of patients do not require therapy. Corticosteroids, most commonly prednisolone, have been the standard treatment for many years. In some patients, this treatment can slow or reverse the course of the disease, but other patients do not respond to steroid therapy. The use of corticosteroids in mild disease is controversial because in many cases the disease remits spontaneously. Additionally, corticosteroids have many recognized dose- and duration-related side effects, and their use is generally limited to severe, progressive, or organ-threatening disease. The influence of corticosteroids or other immunosuppressants on the natural history is unclear.
Scabies, known colloquially as the seven-year itch, is a contagious skin infection that occurs among humans and other animals. It is caused by a tiny and usually not directly visible parasite, the mite Sarcoptes scabiei, which burrows under the host’s skin, causing intense allergic itching. The infection in animals (caused by different but related mite species) is called sarcoptic mange.
The disease may be transmitted from objects but is most often transmitted by direct skin-to-skin contact, with a higher risk with prolonged contact. Initial infections require four to six weeks to become symptomatic. Reinfection, however, may manifest symptoms within as little as 24 hours. Because the symptoms are allergic, their delay in onset is often mirrored by a significant delay in relief after the parasites have been eradicated. Crusted scabies, formerly known as Norwegian scabies, is a more severe form of the infection often associated with immunosuppression.
The disease can be effectively treated with a number of medications. Permethrin cream is the most effective, but expensive compared to other treatments. Crotamiton is less effective, but also nontoxic and soothing. Ivermectin may be used orally and topically. Treatment with lindane preparations has fallen out of favor due to high toxicity and parasite resistance. In order to prevent re-infection, the host’s contacts are also often treated.
The characteristic symptoms of a scabies infection include intense itching and superficial burrows. The burrow tracks are often linear, to the point that a neat “line” of four or more closely-placed and equally-developed mosquito-like “bites,” is almost diagnostic of the disease.
Scarlet fever is a disease caused by exotoxin released by Streptococcus pyogenes. Once a major cause of death, it is now effectively treated with antibiotics. The term scarlatina may be used interchangeably with scarlet fever, though it is commonly used to indicate the less acute form of scarlet fever that is often seen since the beginning of the twentieth century. It is characterized by: sore throat, fever, bright red tongue with a “strawberry” appearance.
Diagnosis of scarlet fever is clinical. The blood test shows marked leukocytosis with neutrophilia and conservated or increased eosinophils, high erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) (both indications of inflammation), and elevation of antistreptolysin O titer. Blood culture is rarely positive, but the streptococci can usually be demonstrated in throat culture. The complications of scarlet fever include septic complications due to spread of streptococcus in blood and immune-mediated complications due to an aberrant immune response.
Other than the occurrence of the diarrhea, the treatment and course of scarlet fever are no different from those of any strep throat. In case of penicillin allergy, clindamycin or erythromycin can be used with success. Patients should no longer be infectious after taking antibiotics for 24 hours. People who have been exposed to scarlet fever should be watched carefully for a full week for symptoms, especially if aged 3 to young adult. It is very important to be tested (throat culture) and if positive, seek treatment.
Schistosomiasis (also known as snail fever) is a parasitic disease caused by several species of trematodes (platyhelminth infection, or “flukes”), a parasitic worm of the genus Schistosoma.
Although it has a low mortality rate, schistosomiasis often is a chronic illness that can damage internal organs and, in children, impair growth and cognitive development. The urinary form of schistosomiasis is associated with increased risks for bladder cancer in adults. Schistosomiasis is the second most socioeconomically devastating parasitic disease after malaria.
This disease is most commonly found in Asia, Africa, and South America, especially in areas where the water contains numerous freshwater snails, which may carry the parasite.
The disease affects many people in developing countries, particularly children who may acquire the disease by swimming or playing in infected water.
Schistosomiasis is readily treated using a single oral dose of the drug praziquantel annually. As with other major parasitic diseases, there is ongoing and extensive research into developing a schistosomiasis vaccine that will prevent the parasite from completing its life cycle in humans. In 2009, Eurogentec Biologics developed a vaccine against bilharziosis in partnership with INSERM and researchers from the Pasteur Institute.
Schizophrenia is a mental disorder characterized by a disintegration of thought processes and of emotional responsiveness. It most commonly manifests as auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, and it is accompanied by significant social or occupational dysfunction. The onset of symptoms typically occurs in young adulthood, with a global lifetime prevalence of about 0.3–0.7%. Diagnosis is based on observed behavior and the patient’s reported experiences.
Genetics, early environment, neurobiology, and psychological and social processes appear to be important contributory factors; some recreational and prescription drugs appear to cause or worsen symptoms. Current research is focused on the role of neurobiology, although no single isolated organic cause has been found. The many possible combinations of symptoms have triggered debate about whether the diagnosis represents a single disorder or a number of discrete syndromes. Despite the etymology of the term from the Greek roots skhizein (σχίζειν, “to split”) and phrēn, phren- (φρήν, φρεν-; “mind”), schizophrenia does not imply a “split mind” and it is not the same as dissociative identity disorder—also known as “multiple personality disorder” or “split personality”—a condition with which it is often confused in public perception.
The mainstay of treatment is antipsychotic medication, which primarily suppresses dopamine, and sometimes serotonin, receptor activity. Psychotherapy and vocational and social rehabilitation are also important in treatment. In more serious cases—where there is risk to self and others—involuntary hospitalization may be necessary, although hospital stays are now shorter and less frequent than they were.
The disorder is thought mainly to affect cognition, but it also usually contributes to chronic problems with behavior and emotion. People with schizophrenia are likely to have additional (comorbid) conditions, including major depression and anxiety disorders; the lifetime occurrence of substance abuse is almost 50%. Social problems, such as long-term unemployment, poverty and homelessness, are common. The average life expectancy of people with the disorder is 12 to 15 years less than those without, the result of increased physical health problems and a higher suicide rate (about 5%).
Sciatica is a set of symptoms including pain that may be caused by general compression and/or irritation of one of five spinal nerve roots that give rise to each sciatic nerve, or by compression or irritation of the left or right or both sciatic nerves. The pain is felt in the lower back, buttock, and/or various parts of the leg and foot. In addition to pain, which is sometimes severe, there may be numbness, muscular weakness, pins and needles or tingling and difficulty in moving or controlling the leg. Typically, the symptoms are only felt on one side of the body. Pain can be severe in prolonged exposure to cold weather.
Although sciatica is a relatively common form of low back pain and leg pain, the true meaning of the term is often misunderstood. Sciatica is a set of symptoms rather than a diagnosis for what is irritating the root of the nerve, causing the pain. This point is important, because treatment for sciatica or sciatic symptoms will often be different, depending upon the underlying cause of the symptoms.
Scleroderma is a chronic systemic autoimmune disease (primarily of the skin) characterized by fibrosis (or hardening), vascular alterations, and autoantibodies. There are two major forms:
Limited systemic sclerosis/scleroderma involves cutaneous manifestations that mainly affect the hands, arms and face. Previously called CREST syndrome in reference to the following complications: Calcinosis, Raynaud’s phenomenon, Esophageal dysfunction, Sclerodactyly, and Telangiectasias. Additionally, pulmonary arterial hypertension may occur in up to one third of patients and is the most serious complication for this form of scleroderma.
Diffuse systemic sclerosis/scleroderma is rapidly progressing and affects a large area of the skin and one or more internal organs, frequently the kidneys, esophagus, heart and lungs. This form of scleroderma can be quite disabling. There are no treatments for scleroderma itself, but individual organ system complications are treated.
Other forms of scleroderma include systemic sine scleroderma, which lacks skin changes, but has systemic manifestations, and two localized forms which affect the skin, but not the internal organs: morphea, and linear scleroderma.
The prognosis is generally good for limited cutaneous scleroderma patients who escape pulmonary complications, but is worse for those with the diffuse cutaneous disease, particularly in older age, and for males. Death occurs most often from pulmonary, heart and kidney complications. In diffuse cutaneous disease, five-year survival is 70%, 10-year survival is 55%.
Scurvy is a disease resulting from a deficiency of vitamin C, which is required for the synthesis of collagen in humans. The chemical name for vitamin C, ascorbic acid, is derived from the Latin name of scurvy, scorbutus, which also provides the adjective scorbutic (“of, characterized by or having to do with scurvy”). Scurvy often presents itself initially as symptoms of malaise and lethargy, followed by formation of spots on the skin, spongy gums, and bleeding from the mucous membranes. Spots are most abundant on the thighs and legs, and a person with the ailment looks pale, feels depressed, and is partially immobilized. As scurvy advances, there can be open, suppurating wounds, loss of teeth, jaundice, fever, neuropathy and death.
Scurvy was at one time common among sailors, pirates and others aboard ships at sea longer than perishable fruits and vegetables could be stored (subsisting instead only on cured and salted meats and dried grains) and by soldiers similarly separated from these foods for extended periods. It was described by Hippocrates (c. 460 BC–c. 380 BC), and herbal cures for scurvy have been known in many native cultures since prehistory. Scurvy was one of the limiting factors of marine travel, often killing large numbers of the passengers and crew on long-distance voyages. This became a significant issue in Europe from the beginning of the modern era in the Age of Discovery in the 15th century, continuing to play a significant role through World War I in the 20th century.
Today scurvy is known to be caused by a nutritional deficiency, but until the isolation of vitamin C and its direct link to scurvy in 1932, numerous theories and treatments were proposed, often on little or no experimental data. This inconsistency is attributed to the lack of vitamin C as a distinct concept, the varying vitamin C content of different foods (notably present in fresh citrus, watercress, and organ meat), and how vitamin C can be destroyed by exposure to air and copper.
Scoliosis is a medical condition in which a person’s spine is curved from side to side. Although it is a complex three-dimensional deformity, on an X-ray, viewed from the rear, the spine of an individual with scoliosis may look more like an “S” or a “C” than a straight line. Scoliosis is typically classified as either congenital (caused by vertebral anomalies present at birth), idiopathic (cause unknown, subclassified as infantile, juvenile, adolescent, or adult, according to when onset occurred), or neuromuscular (having developed as a secondary symptom of another condition, such as spina bifida, cerebral palsy, spinal muscular atrophy, or physical trauma). This condition affects approximately 7 million people in the United States. Patients having reached skeletal maturity are less likely to have a worsening case. Some severe cases of scoliosis can lead to diminishing lung capacity, putting pressure on the heart, and restricting physical activities.
Selective mutism (SM) is an anxiety disorder in which a person, most often a child, who is normally capable of speech is unable to speak in given situations, or to specific people. Selective mutism often co-exists with shyness or (often severe) social anxiety. Children and adults with selective mutism are fully capable of speech and understanding language, but can fail to speak in certain social situations when it is expected of them. The behaviour may be perceived as shyness by others, and can be linked to social anxiety. A child with selective mutism may be completely silent at school for years but speak quite freely or even excessively at home. There appears to be a hierarchical variation among those suffering from this disorder in that some children participate fully in school and appear social but don’t speak, others will speak only to peers but not to adults, others will speak only to adults when asked questions requiring short answers but not to peers in social situations, and still others speak to no one and participate in few, if any, activities presented to them. In its most severe form known as “progressive mutism”, the disorder progresses until the child no longer speaks to anyone at all, not even to close family members.
Particularly in young children, SM can sometimes be confused with an autism spectrum disorder, especially if the child acts particularly withdrawn around his or her diagnostician; this can lead to incorrect treatment.
Seminoma (also known as pure seminoma or classical seminoma) is a germ cell tumor (cancer) of the testis. It is one of the most treatable and curable cancers, with survival >95% in the early stages. Treatment usually requires removal of one testis, but this does not affect fertility or other sexual functioning.
Seminoma originates in the germinal epithelium of the seminiferous tubules. About half of germ cell tumors of the testis are seminomas. The average age of diagnosis is 40 years. This is about 5 to 10 years older than men with other germ cell tumors of the testes. In most cases, they produce masses that are readily felt on testicular self-examination; however, in up to 11 percent of cases, there may be no mass able to be felt, or there may be testicular atrophy. Testicular pain is reported in up to one fifth of cases. Low back pain may occur after metastasis to the retroperitoneum.
Sepsis is a potentially deadly medical condition that is characterized by a whole-body inflammatory state (called a systemic inflammatory response syndrome or SIRS) and the presence of a known or suspected infection. The body may develop this inflammatory response by the immune system to microbes in the blood, urine, lungs, skin, or other tissues. A lay term for sepsis is blood poisoning, also used to describe septicaemia. Severe sepsis is the systemic inflammatory response, plus infection, plus the presence of organ dysfunction.
Septicemia is a related medical term referring to the presence of pathogenic organisms in the bloodstream, leading to sepsis. The term has not been sharply defined. It has been inconsistently used in the past by medical professionals, for example as a synonym of bacteremia, causing some confusion.
Severe sepsis is usually treated in the intensive care unit with intravenous fluids and antibiotics. If fluid replacement isn’t sufficient to maintain blood pressure, specific vasopressor medications can be used. Mechanical ventilation and dialysis may be needed to support the function of the lungs and kidneys, respectively. To guide therapy, a central venous catheter and an arterial catheter may be placed; measurement of other hemodynamic variables (such as cardiac output, or mixed venous oxygen saturation) may also be used. Sepsis patients require preventive measures for deep vein thrombosis, stress ulcers and pressure ulcers, unless other conditions prevent this. Some patients might benefit from tight control of blood sugar levels with insulin (targeting stress hyperglycemia), low-dose corticosteroids or activated drotrecogin alfa (recombinant protein C).
Short bowel syndrome (SBS, also short gut syndrome or simply short gut) is a malabsorption disorder caused by the surgical removal of the small intestine, or rarely due to the complete dysfunction of a large segment of bowel. Most cases are acquired, although some children are born with a congenital short bowel. It usually does not develop unless more than two thirds of the small intestine have been removed.
The symptoms of short bowel syndrome can include: Abdominal pain, Diarrhea and steatorrhea (oily or sticky stool, which can be malodorous), fluid retention, weight loss and malnutrition, fatigue.
Patients with short bowel syndrome may have complications caused by malabsorption of vitamins and minerals, such as deficiencies in vitamins A, D, E, K, and B12, calcium, magnesium, iron, folic acid, and zinc. These may appear as anemia, hyperkeratosis (scaling of the skin), easy bruising, muscle spasms, poor blood clotting, and bone pain.
There is no cure for short bowel syndrome. In newborn infants, the 4-year survival rate on parenteral nutrition is approximately 70%. In newborn infants with less than 10% of expected intestinal length, 5 year survival is approximately 20%. Some studies suggest that much of the mortality is due to a complication of the TPN, especially chronic liver disease. Much hope is vested in Omegaven, a type of lipid TPN feed, in which recent case reports suggest the risk of liver disease is much lower.
Sickle-cell disease (SCD), or sickle-cell anaemia (or anemia; SCA) or drepanocytosis, is an autosomal recessive genetic blood disorder with incomplete dominance, characterized by red blood cells that assume an abnormal, rigid, sickle shape. Sickling decreases the cells’ flexibility and results in a risk of various complications. The sickling occurs because of a mutation in the haemoglobin gene. Life expectancy is shortened, with studies reporting an average life expectancy of 42 in males and 48 in females.
Sickle-cell disease, usually presenting in childhood, occurs more commonly in people (or their descendants) from parts of tropical and sub-tropical regions where malaria is or was common. One-third of all indigenous inhabitants of Sub-Saharan Africa carry the gene, because in areas where malaria is common, there is a fitness benefit in carrying only a single sickle-cell gene (sickle cell trait). Those with only one of the two alleles of the sickle-cell disease, while not totally resistant, are more tolerant to the infection and thus show less severe symptoms when infected.
The prevalence of the disease in the United States is approximately 1 in 5,000, mostly affecting Americans of Sub-Saharan African descent, according to the National Institutes of Health. In the United States, about 1 out of 500 African-American children born will have sickle-cell anaemia.
Sickle-cell anaemia is the name of a specific form of sickle-cell disease in which there is homozygosity for the mutation that causes HbS. Sickle-cell anaemia is also referred to as “HbSS”, “SS disease”, “haemoglobin S” or permutations thereof. In heterozygous people, who have only one sickle gene and one normal adult haemoglobin gene, it is referred to as “HbAS” or “sickle cell trait”. Other, rarer forms of sickle-cell disease include sickle-haemoglobin C disease (HbSC), sickle beta-plus-thalassaemia (HbS/β+) and sickle beta-zero-thalassaemia (HbS/β0). These other forms of sickle-cell disease are compound heterozygous states in which the person has only one copy of the mutation that causes HbS and one copy of another abnormal haemoglobin allele.
The term disease is applied, because the inherited abnormality causes a pathological condition that can lead to death and severe complications. Not all inherited variants of haemoglobin are detrimental, a concept known as genetic polymorphism.
Silicosis, also known as Potter’s rot, is a form of occupational lung disease caused by inhalation of crystalline silica dust, and is marked by inflammation and scarring in forms of nodular lesions in the upper lobes of the lungs. It is a type of pneumoconiosis.
Silicosis (particularly the acute form) is characterized by shortness of breath, cough, fever, and cyanosis (bluish skin). It may often be misdiagnosed as pulmonary edema (fluid in the lungs), pneumonia, or tuberculosis.
The name silicosis (from the Latin silex, or flint) was originally used by Visconti in 1870. The recognition of respiratory problems from breathing in dust dates to ancient Greeks and Romans. Agricola, in the mid-16th century, wrote about lung problems from dust inhalation in miners. In 1713, Bernardino Ramazzini noted asthmatic symptoms and sand-like substances in the lungs of stone cutters. With industrialization, as opposed to hand tools, came increased production of dust. The pneumatic hammer drill was introduced in 1897 and sandblasting was introduced in about 1904, both significantly contributing to the increased prevalence of silicosis.
Sjögren’s syndrome, also known as “Sicca syndrome”, is a systemic autoimmune disease in which immune cells attack and destroy the exocrine glands that produce tears and saliva. It is named after Swedish ophthalmologist Henrik Sjögren (1899–1986), who first described it.
Nine out of ten Sjögren’s patients are women and the average age of onset is late 40s, although Sjögren’s occurs in all age groups in both women and men. It is estimated to strike as many as 4 million people in the United States alone, making it the second most common autoimmune rheumatic disease.
Sjögren’s syndrome can exist as a disorder in its own right (primary Sjögren’s syndrome) or may develop years after the onset of an associated rheumatic disorder, such as rheumatoid arthritis, systemic lupus erythematosus, scleroderma, primary biliary cirrhosis etc. (secondary Sjögren’s syndrome)
Smallpox is an infectious disease unique to humans, caused by either of two virus variants, Variola major and Variola minor.The disease is also known by the Latin names Variola or Variola vera, which is a derivative of the Latin varius, meaning “spotted”, or varus, meaning “pimple”. The term “smallpox” was first used in Europe in the 15th century to distinguish variola from the “great pox” (syphilis).Smallpox localizes in small blood vessels of the skin and in the mouth and throat. In the skin, this results in a characteristic maculopapular rash, and later, raised fluid-filled blisters. V. major produces a more serious disease and has an overall mortality rate of 30–35%. V. minor causes a milder form of disease (also known as alastrim, cottonpox, milkpox, whitepox, and Cuban itch) which kills about 1% of its victims. Long-term complications of V. major infection include characteristic scars, commonly on the face, which occur in 65–85% of survivors. Blindness resulting from corneal ulceration and scarring, and limb deformities due to arthritis and osteomyelitis are less common complications, seen in about 2–5% of cases.
Smallpox is believed to have emerged in human populations about 10,000 BC. The earliest physical evidence of smallpox is probably the pustular rash on the mummified body of Pharaoh Ramses V of Egypt. The disease killed an estimated 400,000 Europeans per year during the closing years of the 18th century (including five reigning monarchs), and was responsible for a third of all blindness.Of all those infected, 20–60%—and over 80% of infected children—died from the disease. Smallpox was responsible for an estimated 300–500 million deaths during the 20th century. As recently as 1967, the World Health Organization (WHO) estimated that 15 million people contracted the disease and that two million died in that year.After vaccination campaigns throughout the 19th and 20th centuries, the WHO certified the eradication of smallpox in 1979. Smallpox is one of the two infectious diseases to have been eradicated, the other being rinderpest, which was declared eradicated in 2011.
Spasmodic dysphonia (or laryngeal dystonia) is a voice disorder characterized by involuntary movements of one or more muscles of the larynx (vocal folds or voice box) during speech. The exact cause of spasmodic dysphonia (SD) is unknown. According to the National Institute on Deafness and Other Communication Disorders “research has revealed increasing evidence that most cases of spasmodic dysphonia are in fact neurogenic or having to do with the nervous system (brain and nerves).”
SD is a neurological disorder rather than a disorder of the larynx, and as in other forms of dystonia, interventions at the end organ (i.e., larynx) have not offered a definitive cure, only symptomatic relief. The pathophysiology underlying dystonia is becoming better understood as a result of discoveries in genetically based forms of the disorder, and this approach is the most promising avenue to a long-term solution.
There is no known cure for spasmodic dysphonia.
The most effective treatment for reducing the symptoms of spasmodic dysphonia is injections of very small amounts of botulinum toxin (sold commercially under the brand names Botox, Dysport, and Myobloc) directly into the affected muscles of the larynx. The toxin weakens muscles by blocking the nerve impulse to the muscle. The botulinum toxin injections generally improve the voice for a period of three to four months after which the voice symptoms gradually return. This treatment requires continual injections to maintain a good speaking voice.
Strabismus is a condition in which the eyes are not properly aligned with each other. It typically involves a lack of coordination between the extraocular muscles, which prevents bringing the gaze of each eye to the same point in space and preventing proper binocular vision, which may adversely affect depth perception.
Strabismus can be either a disorder of the brain in coordinating the eyes, or of one or more of the relevant muscles’ power or direction of motion. Difficult strabismus problems are usually co-managed between orthoptists and ophthalmologists.
As with other binocular vision disorders, the primary therapeutic goal for those with strabismus is comfortable, single, clear, normal binocular vision at all distances and directions of gaze.
Whereas amblyopia (lazy eye), if minor and detected early, can often be corrected with use of an eyepatch on the dominant eye and/or vision therapy, the use of eyepatches is unlikely to change the angle of strabismus. Advanced strabismus is usually treated with a combination of eyeglasses or prisms, vision therapy, and surgery, depending on the underlying reason for the misalignment. Surgery does not change the vision; it attempts to align the eyes by shortening, lengthening, or changing the position of one or more of the extraocular eye muscles and is frequently the only way to achieve cosmetic improvement. The procedure can typically be performed in about an hour, and requires about a week for recovery. Double vision can result, and occasionally vision loss can occur. Glasses affect the position by changing the person’s reaction to focusing. Prisms change the way light, and therefore images, strike the eye, simulating a change in the eye position.
Swine influenza, also called pig blue influenza, swine flu, hog flu and pig flu, is an infection by any one of several types of swine influenza virus. Swine influenza virus (SIV) or S-OIV (swine-origin influenza virus) is any strain of the influenza family of viruses that is endemic in pigs. As of 2009, the known SIV strains include influenza C and the subtypes of influenza A known as H1N1, H1N2, H3N1, H3N2, and H2N3.
Swine influenza virus is common throughout pig populations worldwide. Transmission of the virus from pigs to humans is not common and does not always lead to human flu, often resulting only in the production of antibodies in the blood. If transmission does cause human flu, it is called zoonotic swine flu. People with regular exposure to pigs are at increased risk of swine flu infection. The meat of an infected animal poses no risk of infection when properly cooked.
During the mid-20th century, identification of influenza subtypes became possible, allowing accurate diagnosis of transmission to humans. Since then, only 50 such transmissions have been confirmed. These strains of swine flu rarely pass from human to human. Symptoms of zoonotic swine flu in humans are similar to those of influenza and of influenza-like illness in general, namely chills, fever, sore throat, muscle pains, severe headache, coughing, weakness and general discomfort.
Synesthesia is a neurologically based condition in which stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway. People who report such experiences are known as synesthetes.
In one common form of synesthesia, known as grapheme → color synesthesia or color-graphemic synesthesia, letters or numbers are perceived as inherently colored, while in ordinal linguistic personification, numbers, days of the week and months of the year evoke personalities. In spatial-sequence, or number form synesthesia, numbers, months of the year, and/or days of the week elicit precise locations in space (for example, 1980 may be “farther away” than 1990), or may have a (three-dimensional) view of a year as a map (clockwise or counterclockwise). Yet another recently identified type, visual motion → sound synesthesia, involves hearing sounds in response to visual motion and flicker. Over 60 types of synesthesia have been reported, but only a fraction have been evaluated by scientific research. Even within one type, synesthetic perceptions vary in intensity and people vary in awareness of their synesthetic perceptions.
Synesthetes often report that they were unaware their experiences were unusual until they realized other people did not have them, while others report feeling as if they had been keeping a secret their entire lives, as has been documented in interviews with synesthetes on how they discovered synesthesia in their childhood. The automatic and ineffable nature of a synesthetic experience means that the pairing may not seem out of the ordinary. This involuntary and consistent nature helps define synesthesia as a real experience. Most synesthetes report that their experiences are pleasant or neutral, although, in rare cases, synesthetes report that their experiences can lead to a degree of sensory overload.
Syphilis is a sexually transmitted infection caused by the spirochete bacteria Treponema pallidum subspecies pallidum. The primary route of transmission is through sexual contact however it may also be transmitted from mother to fetus during pregnancy or at birth resulting in congenital syphilis. Other human diseases caused by related Treponema pallidum include yaws (subspecies pertenue), pinta (subspecies carateum) and bejel (subspecies endemicum).
The signs and symptoms of syphilis vary depending in which of the four stages it presents (primary, secondary, latent, and tertiary). The primary stage classically presents with a single chancre (a firm, painless, non-itchy skin ulceration), secondary syphilis with a diffuse rash which frequently involves the palms of the hands and soles of the feet, latent syphilis with little to no symptoms, and tertiary syphilis with gummas, neurological, or cardiac symptoms. It has however been known as “the great imitator” due to its frequent atypical presentations. Diagnosis is usually via blood tests however the bacteria can also be visualized under a microscope. Syphilis can be effectively treated with antibiotics, specifically intramuscular penicillin G and in those who are allergic ceftriaxone is recommended.
Syphilis is believed to have infected 12 million people worldwide in 1999, with greater than 90% of cases in the developing world. After decreasing dramatically since the widespread availability of penicillin in 1940s, rates of infection have increased since the turn of the millennium in many countries often in combination with human immunodeficiency virus (HIV). This has been attributed partly to unsafe sexual practices among men who have sex with men, increased promiscuity, prostitution and decreasing use of barrier protection.