What is Ebola virus disease ?

"Ebola" redirects here. For other uses, see Ebola (disambiguation).

Ebola virus disease
Two nurses standing near Mayinga N'Seka, a nurse with Ebola virus disease in the 1976 outbreak in Zaire. N'Seka died a few days later.

Ebola virus disease (EVD; also Ebola hemorrhagic fever, or EHF), or simply Ebola, is a disease of humans and other primatescaused by ebolaviruses. Signs and symptoms typically start between two days and three weeks after contracting the virus with afever, sore throat, muscular pain, and headaches. Then, vomiting, diarrhea and rash usually follow, along with decreased function of the liver and kidneys. At this time some people begin to bleed both internally and externally. The disease has a high risk of death, killing between 25 and 90 percent of those infected with an average of about 50 percent.This is often due to low blood pressure from fluid loss, and typically follows six to sixteen days after symptoms appear.

The virus spreads by direct contact with body fluids, such as blood, of an infected human or other animals.This may also occur through contact with an item recently contaminated with bodily fluids. Spread of the disease through the air between primates, including humans, has not been documented in either laboratory or natural conditions.Semen or breast milk of a person after recovery from EVD may still carry the virus for several weeks to months. Fruit bats are believed to be the normal carrier in nature, able to spread the virus without being affected by it. Other diseases such as malaria, cholera, typhoid fever, meningitis and other viral hemorrhagic fevers may resemble EVD. Blood samples are tested for viral RNA, viral antibodies or for the virus itself to confirm the diagnosis.

Control of outbreaks requires coordinated medical services, alongside a certain level of community engagement. The medical services include rapid detection of cases of disease, contact tracing of those who have come into contact with infected individuals, quick access to laboratory services, proper healthcare for those who are infected, and proper disposal of the dead through cremationor burial.Samples of body fluids and tissues from people with the disease should be handled with special caution. Prevention includes limiting the spread of disease from infected animals to humans. This may be done by handling potentially infected bush meatonly while wearing protective clothing and by thoroughly cooking it before eating it. It also includes wearing proper protective clothing and washing hands when around a person with the disease.

No specific treatment or vaccine for the virus is available, although a number of potential treatments are being studied. Supportive efforts, however, improve outcomes. This includes either oral rehydration therapy (drinking slightly sweetened and salty water) or giving intravenous fluids as well as treating symptoms. The disease was first identified in 1976 in two simultaneous outbreaks, one inNzara, and the other in Yambuku, a village near the Ebola River from which the disease takes its name. EVD outbreaks occur intermittently in tropical regions of sub-Saharan Africa. Between 1976 and 2013, the World Health Organization reports a total of 24 outbreaks involving 1,716 cases. The largest outbreak is the ongoing epidemic in West Africa centered in Guinea, Sierra Leoneand Liberia. As of 28 March 2015, this outbreak has 25,065 reported cases resulting in 10,413 deaths.

Signs and symptoms

Signs and symptoms of Ebola

The length of time between exposure to the virus and the development of symptoms (incubation period) is between 2 to 21 days,usually between 4 to 10 days. However, recent estimates based on mathematical models predict that around 5% of cases may take greater than 21 days to develop.

Symptoms usually begin with a sudden influenza-like stage characterized by feeling tired, fever, weakness, decreased appetite, muscular pain, joint pain, headache, and sore throat. The fever is usually higher than 38.3 °C (101 °F). This is often followed by vomiting, diarrhea and abdominal pain.^[16] Next, shortness of breath and chest pain may occur, along with swelling, headaches andconfusion. In about half of the cases, the skin may develop a maculopapular rash, a flat red area covered with small bumps, 5 to 7 days after symptoms begin.

In some cases, internal and external bleeding may occur.This typically begins five to seven days after the first symptoms.All infected people show some decreased blood clotting. Bleeding from mucous membranes or from sites of needle punctures has been reported in 40–50 percent of cases. This may cause vomiting blood, coughing up of blood, or blood in stool.Bleeding into the skin may createpetechiae, purpura, ecchymoses or hematomas (especially around needle injection sites). Bleeding into the whites of the eyes may also occur. Heavy bleeding is uncommon; if it occurs, it is usually located within the gastrointestinal tract.

Recovery may begin between 7 and 14 days after first symptoms. Death, if it occurs, follows typically 6 to 16 days from first symptoms and is often due to low blood pressure from fluid loss. In general, bleeding often indicates a worse outcome, and blood loss may result in death.People are often in a coma near the end of life.Those who survive often have ongoing muscular and joint pain, liver inflammation, decreased hearing, and may have constitutional symptoms such as feeling tired, continued weakness, decreased appetite, and difficulty returning to pre-illness weight.Additionally they develop antibodies against Ebola that last at least 10 years, but it is unclear if they are immune to repeated infections. If someone recovers from Ebola, they can no longer transmit the disease.

source : http://en.wikipedia.org

What is Abscess ??

This article is about the medical condition. For the death metal band, see Abscess (band).

Abscess
Five-day-old abscess. The black dot is a clogged hair follicle.

An abscess (Latin: abscessus) is a collection of pus that has built up within the tissue of the body. Signs and symptoms of abscesses include: redness, pain, warmth, and swelling that when pressed feels like it is fluid filled.The area of redness often extends beyond the swelling.Carbuncles and furuncles are types of abscess that often involves hair follicles with carbuncles being larger.

They are usually caused by a bacterial infection.Often many different types of bacteria are involved in a single infection. In the United States and many other areas of the world the most common bacteria present is methicillin-resistant Staphylococcus aureus.Rarely parasites can cause abscesses and this is more common in the developing world.Diagnosis of a skin abscess is usually made based on what it looks like and is confirmed by cutting it open. Ultrasound imaging may be useful in cases in which the diagnosis is not clear.In abscesses around the anus, computer tomography (CT) may be important to look for deeper infection.

Standard treatment for most skin or soft tissue abscesses is cutting it open and drainage.There does not appear to be any benefit from also using antibiotics for this type of abscess in most people who are otherwise healthy. A small amount of evidence supports not packing with gauze the cavity that remains after drainage.Closing this cavity right after draining it rather than leaving it open may speed healing without increasing the risk of the abscess returning. Sucking out the pus with a needle is often not sufficient.

Skin abscesses are common and have become more common in recent years. Risk factors include intravenous drug use with rates reported as high as 65% in this population. In 2005 in the United States 3.2 million people went to the emergency department for an abscess. In Australia around 13,000 people were hospitalized in 2008 for the disease.

source : http://en.wikipedia.org

What is Meningitis ?

Meningitis
Meninges of the central nervous system: dura mater, arachnoid, and pia mater.

Meningitis (from Greek μῆνιγξ méninx, "membrane"^[1] and the medical suffix -itis, "inflammation") is an acute inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs.Meningitis can be life-threatening because of the inflammation's proximity to the brain and spinal cord; therefore, the condition is classified as a medical emergency.

The most common symptoms of meningitis are headache and neck stiffness associated with fever, confusion or alteredconsciousness, vomiting, and an inability to tolerate light (photophobia) or loud noises (phonophobia). Children often exhibit onlynonspecific symptoms, such as irritability and drowsiness. If a rash is present, it may indicate a particular cause of meningitis; for instance, meningitis caused by meningococcal bacteria may be accompanied by a characteristic rash.

A lumbar puncture diagnoses or excludes meningitis. A needle is inserted into the spinal canal to extract a sample of cerebrospinal fluid (CSF), that envelops the brain and spinal cord. The CSF is examined in a medical laboratory.The first treatment in acute meningitis consists of promptly administered antibiotics and sometimes antiviral drugs. Corticosteroids can also be used to prevent complications from excessive inflammation.Meningitis can lead to serious long-term consequences such as deafness, epilepsy,hydrocephalus and cognitive deficits, especially if not treated quickly.Some forms of meningitis (such as those associated withmeningococci, Haemophilus influenzae type B, pneumococci or mumps virus infections) may be prevented by immunization. In 2013 meningitis resulted in 303,000 deaths – down from 464,000 deaths in 1990.

Signs and symptoms

Clinical features

Neck stiffness, Texas meningitis epidemic of 1911–12.

In adults, the most common symptom of meningitis is a severe headache, occurring in almost 90% of cases of bacterial meningitis, followed by nuchal rigidity (the inability to flex the neck forward passively due to increased neck muscle tone and stiffness).The classic triad of diagnostic signs consists of nuchal rigidity, sudden high fever, and altered mental status; however, all three features are present in only 44–46% of bacterial meningitis cases. If none of the three signs are present, acute meningitis is extremely unlikely. Other signs commonly associated with meningitis include photophobia (intolerance to bright light) and phonophobia (intolerance to loud noises). Small children often do not exhibit the aforementioned symptoms, and may only be irritable and look unwell. The fontanelle (the soft spot on the top of a baby's head) can bulge in infants aged up to 6 months. Other features that distinguish meningitis from less severe illnesses in young children are leg pain, cold extremities, and an abnormal skin color.

Nuchal rigidity occurs in 70% of bacterial meningitis in adults. Other signs of meningism include the presence of positive Kernig's sign orBrudziński sign. Kernig's sign is assessed with the person lying supine, with the hip and knee flexed to 90 degrees. In a person with a positive Kernig's sign, pain limits passive extension of the knee. A positive Brudzinski's sign occurs when flexion of the neck causes involuntary flexion of the knee and hip. Although Kernig's sign and Brudzinski's sign are both commonly used to screen for meningitis, the sensitivity of these tests is limited.They do, however, have very goodspecificity for meningitis: the signs rarely occur in other diseases.Another test, known as the "jolt accentuation maneuver" helps determine whether meningitis is present in those reporting fever and headache. A person is asked to rapidly rotate the head horizontally; if this does not make the headache worse, meningitis is unlikely.

Meningitis caused by the bacterium Neisseria meningitidis (known as "meningococcal meningitis") can be differentiated from meningitis with other causes by a rapidly spreadingpetechial rash, which may precede other symptoms. The rash consists of numerous small, irregular purple or red spots ("petechiae") on the trunk, lower extremities, mucous membranes, conjuctiva, and (occasionally) the palms of the hands or soles of the feet. The rash is typically non-blanching; the redness does not disappear when pressed with a finger or a glass tumbler. Although this rash is not necessarily present in meningococcal meningitis, it is relatively specific for the disease; it does, however, occasionally occur in meningitis due to other bacteria.Other clues on the cause of meningitis may be the skin signs of hand, foot and mouth disease and genital herpes, both of which are associated with various forms of viral meningitis.

Early complications

Charlotte Cleverley-Bismandeveloped severe meningococcal meningitis as a young child; in her case, the petechial rash progressed to gangrene and required amputation of all limbs. She survived the disease and became a poster child for a meningitis vaccination campaign inNew Zealand.

Additional problems may occur in the early stage of the illness. These may require specific treatment, and sometimes indicate severe illness or worse prognosis. The infection may trigger sepsis, a systemic inflammatory response syndrome of falling blood pressure, fast heart rate, high or abnormally low temperature, and rapid breathing. Very low blood pressure may occur at an early stage, especially but not exclusively in meningococcal meningitis; this may lead to insufficient blood supply to other organs.Disseminated intravascular coagulation, the excessive activation of blood clotting, may obstruct blood flow to organs and paradoxically increase the bleeding risk. Gangrene of limbs can occur in meningococcal disease.Severe meningococcal and pneumococcal infections may result in hemorrhaging of the adrenal glands, leading toWaterhouse-Friderichsen syndrome, which is often fatal.

The brain tissue may swell, pressure inside the skull may increase and the swollen brain may herniate through the skull base. This may be noticed by a decreasing level of consciousness, loss of the pupillary light reflex, and abnormal posturing. The inflammation of the brain tissue may also obstruct the normal flow of CSF around the brain (hydrocephalus).Seizures may occur for various reasons; in children, seizures are common in the early stages of meningitis (in 30% of cases) and do not necessarily indicate an underlying cause.Seizures may result from increased pressure and from areas of inflammation in the brain tissue. Focal seizures (seizures that involve one limb or part of the body), persistent seizures, late-onset seizures and those that are difficult to control with medication indicate a poorer long-term outcome.

Inflammation of the meninges may lead to abnormalities of the cranial nerves, a group of nerves arising from the brain stem that supply the head and neck area and which control, among other functions, eye movement, facial muscles, and hearing.Visual symptoms and hearing loss may persist after an episode of meningitis. Inflammation of the brain (encephalitis) or its blood vessels (cerebral vasculitis), as well as the formation of blood clots in the veins (cerebral venous thrombosis), may all lead to weakness, loss of sensation, or abnormal movement or function of the part of the body supplied by the affected area of the brain.

source : http://en.wikipedia.org

What is Obesity ?

Obesity

Obesity
Silhouettes and waist circumferences representing normal, overweight, and obese

Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have a negative effect on health, leading to reduced life expectancy and/or increased health problems.In Western countries, people are considered obese when their body mass index (BMI),a measurement obtained by dividing a person's weight by the square of the person's height, exceeds30 kg/m², with the range 25-30 kg/m² defined as overweight. Some East Asian countries use stricter criteria.

Obesity increases the likelihood of various diseases, particularly heart disease, type 2 diabetes, obstructive sleep apnea, certain types of cancer, and osteoarthritis. Obesity is most commonly caused by a combination of excessive food energy intake, lack of physical activity, and genetic susceptibility, although a few cases are caused primarily by genes, endocrine disorders, medications, orpsychiatric illness. Evidence to support the view that some obese people eat little yet gain weight due to a slow metabolism is limited. On average, obese people have a greater energy expenditure than their thin counterparts due to the energy required to maintain an increased body mass.

Dieting and exercising are the main treatments for obesity. Diet quality can be improved by reducing the consumption of energy-dense foods, such as those high in fat and sugars, and by increasing the intake of dietary fiber. With a suitable diet, anti-obesity drugs may be taken to reduce appetite or decrease fat absorption. If diet, exercise, and medication are not effective, a gastric balloonmay assist with weight loss, or surgery may be performed to reduce stomach volume and/or bowel length, leading to feeling full earlier and a reduced ability to absorb nutrients from food.

Obesity is a leading preventable cause of death worldwide, with increasing rates in adults and children. Authorities view it as one of the most serious public health problems of the 21st century. Obesity is stigmatized in much of the modern world (particularly in theWestern world), though it was widely seen as a symbol of wealth and fertility at other times in history and still is in some parts of the world. In 2013, the American Medical Association classified obesity as a disease.

Classification

A "super obese" male with a BMI of 47 kg/m²: weight 146 kg (322 lb), height 177 cm (5 ft 10 in

Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health.It is defined by body mass index (BMI) and further evaluated in terms of fat distribution via the waist–hip ratio and total cardiovascular risk factors.BMI is closely related to both percentage body fat and total body fat.

In children, a healthy weight varies with age and sex. Obesity in children and adolescents is defined not as an absolute number but in relation to a historical normal group, such that obesity is a BMI greater than the 95th percentile. The reference data on which these percentiles were based date from 1963 to 1994, and thus have not been affected by the recent increases in weight.

BMI (kg/m2)		Classification
from	up to
	18.5	underweight
18.5	25.0	normal weight
25.0	30.0	overweight
30.0	35.0	class I obesity
35.0	40.0	class II obesity
40.0		class III obesity

BMI is defined as the subject's weight divided by the square of their height and is calculated as follows.

,

where m and h are the subject's weight and height respectively.

BMI is usually expressed in kilograms per square metre, resulting when weight is measured in kilograms and height in metres. To convert from pounds per square inch multiply by703 (kg/m²)/(lb/sq in).

The most commonly used definitions, established by the World Health Organization (WHO) in 1997 and published in 2000, provide the values listed in the table at right.

Some modifications to the WHO definitions have been made by particular bodies. The surgical literature breaks down "class III" obesity into further categories whose exact values are still disputed.

• Any BMI ≥ 35 or 40 kg/m² is severe obesity.
• A BMI of ≥ 35 kg/m² and experiencing obesity-related health conditions or ≥40–44.9 kg/m² is morbid obesity.
• A BMI of ≥ 45 or 50 kg/m² is super obesity.

As Asian populations develop negative health consequences at a lower BMI than Caucasians, some nations have redefined obesity; the Japanese have defined obesity as any BMI greater than 25 kg/m² while China uses a BMI of greater than 28 kg/m².

Effects on health

Excessive body weight is associated with various diseases, particularly cardiovascular diseases, diabetes mellitus type 2, obstructive sleep apnea, certain types of cancer,osteoarthritis and asthma. As a result, obesity has been found to reduce life expectancy.

source : http://en.wikipedia.org