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COMMON COLD

What is the common cold, and what causes it? The common cold also known as a viral upper respiratory tract infection is a self-limited contagious illness that can be caused by a number of different types of viruses. More than 200 different types of viruses are known to cause the common cold. Because so many different viruses can cause a cold and because new cold viruses constantly develop, the body never builds up resistance against all of them. For this reason colds are a frequent and recurring problem. In fact children in preschool and elementary school can have 3 to 12 cold per year while adolescents and adults typically have 2 to 4 colds per year. The common cold is the most frequently occurring illness in the world and it is a leading cause of doctor visits and missed days from school and work.

What are the symptoms of the common cold? Symptoms of the common cold include nasal stuffiness or drainage, sore or scratchy throat, sneezing, hoarseness, cough, and perhaps a fever and headache. Many people with a cold feel tired and achy. These symptoms will typically last anywhere from 3 to 10 days.

How is the common cold spread? The common cold is usually spread by direct hand-to-hand contact with infected secretions or from contaminated surfaces. For example, if a person with a cold blows or touches his nose and then touches someone else’s, that person can subsequently become infected with the virus. Additionally, a cold virus can live on objects such as pens, books, telephones, computer keyboards, and coffee cups for several hours and can thus be acquired from contact with these objects.

Does it have anything to do with exposure to cold weather? Though the common cold usually occurs in the fall and winter months the cold weather itself does not cause the common cold. Rather, it is thought that during cold weather months people spend more time indoors in close proximity to each other thus facilitating the spread of the virus. For the same reason, children in day care and school are particularly prone to acquiring the common cold.

What is the difference between the common cold and influenza (the flu)? Many people confuse the common cold with influenza (the flu). Influenza is caused by the influenza virus while the common cold generally is not. While some of the symptoms of the common cold and influenza may be similar patients with the common cold typically have a milder illness. Patients with influenza are usually sicker and have a more abrupt onset of illness with fever, chills, headache, body aches, dry cough, and extreme weakness. Though differentiating between the common cold and influenza can be difficult, there is laboratory testing available to confirm the diagnoses of influenza.

What is the treatment for the common cold? There is no cure for the common cold. Home treatment is directed at alleviating the symptoms associated with the common cold and allowing this self-limiting illness to run its course. Supportive measures for the common cold include rest and drinking plenty of fluids. Over-the-counter medications such as throat lozenges, throat sprays, cough drops, and cough syrups may also help bring relief. Decongestants such as pseudoephedrine (Sudafed) or antihistamines may be used for nasal symptoms. Saline sprays and a humidifier may also be beneficial. Do not use aspirin or aspirin containing medications in children or teenagers because they have been associated with a rare potentially fatal condition called Reye’s syndrome.

Are antibiotics a suitable treatment for the common cold? No. Antibiotics play no role in treating the common cold. Antibiotics are effective only against illnesses caused by bacteria, and colds are caused by viruses. Not only do antibiotics not help but they cal also cause allergic reactions that can be fatal (1: 40, 000). Furthermore, using antibiotics when they are not necessary has led to the growth of several strains of common bacteria that have become resistant to certain antibiotics (including one that commonly causes ear infections in children). For these anf other reasons it is important to limit the use of antibiotics to situations in which they are medically indicated.

Though occasionally a bacterial infection such as sinusitis or a middle ear infection can develop following a cold, treatment with antibiotics should be left at the discretion of your physician or health-care practitioner.

How do you prevent the common cold? The most important measure to prevent the common cold is frequent hand washing as this can destroy viruses that you have acquired from touching contaminated surfaces. Also. try to avoid sharing utensils and try to use disposable items (such as disposable cups) if someone in your family has a cold. Finally, lifestyle modifications such as smoking cessation and stress management may decrease susceptibility to acquiring the common cold.

 

RUBELLA

Rubella – commonly known as German measles or 3-day measles – is an infection that primarily affects the skin and the lymph nodes. It is caused by the rubella virus (not the same virus that causes measles) which is usually transmitted by droplets from the nose and throat that others breathe in. It can also pass through a pregnant woman’s bloodstream to infect her unborn child. As this is a generally mild disease in children, the primary medical danger of rubella is the infection of pregnant women which may cause congenital rubella syndrome in developing babies.

Before a vaccine against rubella became available in 1969, rubella epidemics occurred every 6 to 9 years. Kids aged 5 to 9 were primarily affected and many cases of congenital rubella occurred as well. Now, due to immunization of children there are much fewer cases of rubella and congenital rubella.

Most rubella infections today appear in young, non-immunized adults rather than children. In fact, experts estimate that 10% of young adults are currently susceptible to rubella which could pose a danger to any children they might have someday.

Signs and symptoms. Rubella infection may begin with 1 or 2 days of mild fever (99-100 degrees Fahrenheit or 37.2-37.8 degrees Celsius) and swollen, tender lymph nodes usually in the back of the neck or behind the ears. A rash then appears that begins on the face and spreads downward. As it spreads down the body it usually clears on the face. This rash is often the first sign of illness that a parent notices. The rubella rash can look like many other viral rashes. It appears as either pink or light red spots which may merge to form evenly colored patches. The rash can itch and lasts up to 3 days. As the rash clears, the affected skin occasionally sheds in very fine flakes.

Other symptoms of rubella which are more common in teens and adults may include: headache, loss of appetite, mild conjunctivitis (inflammation of the lining of the eyelids and eyeballs), a stuffy or running nose, swollen lymph nodes in other parts of the body, and pain and swelling in the joints (especially in young women). Many people with rubella have few or no symptoms at all.

When rubella occurs in a pregnant woman it may cause congenital rubella syndrome with potentially devastating consequences for the developing fetus. Children who are infected with rubella before birth are at risk for growth retardation, mental retardation, malformations of the heart and eyes, deafness, and liver, spleen, and bone marrow problems.

Contagiousness. Therubellavirus passes from person to person through tiny drops of fluid from the nose and throat. People who have rubella are most contagious from 1 week before to 1 week after the rash appears. Someone who is infected but has no symptoms can still spread the virus. Infants who have congenital rubella syndrome can shed the virus in urine and fluid from the nose and throat for a year or more and may pass the virus to people who have not been immunized.

Prevention. Rubella can be prevented by a rubella vaccine. Widespread immunization against rubella is critical to controlling the spread of the disease, thereby preventing birth defects caused by congenital rubella syndrome. The vaccine is usually given to children at 12 to 15 months of age as part of the scheduled measles-mumps-rubella (MMR) immunization. A second dose of MMR is generally given at 4 to 6 years of age. As in the case with all immunization schedules there are important exceptions and special circumstances. Your child’s doctor will have the most current information.

The rubella vaccine should not be given to pregnant women or to a woman who may become pregnant within 1 month of receiving the vaccine. If you are thinking about becoming pregnant, make sure that you are immune to rubella through a blood test or proof of immunization. If you are not immune you should receive the vaccine at least 1 month before you become pregnant. Pregnant women who are not immune should avoid anyone who has the illness and should be vaccinated after delivery so that they will be immune during any future pregnancies.

Incubation. The incubation period for rubella is 14-23 days, with an average incubation period of 16-18 days. This means that it can take 2-3 weeks for a child to get rubella after they are exposed to someone with the disease.

Duration. The rubella rash typically lasts 3 days. Lymph nodes may remain swollen for a week or more and joint pain can last for more than 2 weeks. Children who have rubella usually recover within 1 week but adults may take longer.

Professional treatment. Rubella cannot be treated with antibiotics because antibiotics do not work against viral infections. Unless there are complications rubella will resolve on its own. Any pregnant woman who has been exposed to rubella should contact her obstetrician immediately.

Home treatment. Rubella is typically a mild illness, especially in kids. Infected children usually can be cared for at home. Monitor your child’s temperature and call the doctor if the fever climbs too high. To relieve minor discomfort you can give your child acetaminophen or ibuprofen. Avoid giving aspirin to a child who has a viral illness because its use in such cases has been associated with the development of Reye’s syndrome which can lead to liver failure and death.

When to call a doctor. Call a doctor if your child develops a fever of 102 degrees F (38.9 degrees C) or above or if your child appears to be getting sicker than the mild course of symptoms described above.

SMALLPOX

Smallpox is a disfiguring and potentially deadly infectious disease caused by the Variola major virus. Few other illnesses have had such a profound effect on human health and history. In the 20th century alone an estimated 300 million people died of smallpox. Before smallpox was eradicated there were two forms of the disease worldwide: Variola major, the deadly disease, and Variola minor, a much milder form. According to some health experts, over the centuries smallpox was responsible for more deaths than all other infectious diseases combined. The disease spreads in any climate and during all seasons. Although a worldwide immunization program eradicated smallpox disease decades ago, small quantities of smallpox virus officially still exist in two research laboratories in Atlanta, Georgia and in Russia.

The last naturally occurring case of smallpox was reported in 1977. In 1980 the World Health Organization declared that smallpox had been eradicated. Currently there is no evidence of naturally occurring smallpox transmission anywhere in the world.

The microbe. Scientists have not studied Variola virus well because of the hazards associated with potential exposure. In addition, by international agreement smallpox may only be studied at the Centers for Disease Control and Prevention (CDC) high containment facility or one in the former USSR and experiments must be approved in advance by an international committee. Vaccinia virus, however, used to make a smallpox vaccine and closely related to Variola has been studied thoroughly. There is one major difference between the two viruses: Vaccinia can infect several types of living beings, while Variola infects only humans naturally and cynomolgus monkeys under highly artificial laboratory conditions. Researchers are now investigating Vaccinia as a possible way to deliver genes from other viruses to make new vaccines.

Transmission. Smallpox is highly contagious. In most cases people get smallpox by inhaling droplets of saliva which are full of virus during face-to-face contact with an infected person. When someone becomes infected they do not immediately feel sick or shed virus to their household contacts. In addition, they have no symptoms for 10 to 12 days. After the virus has multiplied and spread throughout the body, a rash and fever develop. This is the “illness” portion of the disease and it’s when someone is most infectious. In short, someone who becomes infected is not going to be ill until 10 to 12 days later.

Some risk of transmission lasts, however, until all scabs have fallen off. Contaminated clothing or bed linens also can spread the virus. Those caring for people with smallpox need to use special safety measures to ensure that all bedding and clothing from the infected person are cleaned appropriately with bleach and hot water. Caretakers can use disinfectants such as bleach and ammonia to clean contaminated surfaces.

Symptoms. Symptoms of smallpox infection usually appear within 7 to 17 days after exposure to the virus, and on average appear after 12 days. The first symptoms of smallpox may be difficult to distinguish from other flu-like illnesses and include high fever, tiredness, malaise, headache, and backache. A characteristic rash most prominent on the face, arms, and legs follows 2 to 3 days after the first symptoms. The rash starts with flat red lesions (sores) that develop at the same rate. After a few days, the lesions become filled with pus and they begin to crust early in the second week. Scabs develop and then separate and fall off after about 3 weeks.

There is no proven treatment for smallpox. People with the disease can benefit from intravenous fluids and medicine to control fever or pain as well as antibiotics for any secondary bacterial infections that may occur. If an infected person gets the smallpox vaccine within 4 days after exposure to the virus it may lessen the severity of illness or even prevent it. The majority of people with smallpox recover but death may occur in up to 30 percent of cases. Those who do recover are often left with disfiguring scars.

Getting the vaccine. Health care providers use a hypodermic needle, usually used for vaccinations to give the smallpox vaccine. Instead, they use a tiny, two-pronged needle that is dipped into the vaccine solution. When removed, the needle keeps a droplet of the vaccine. The needle is used to prick the skin, usually in the upper arm, a number of times within a few seconds. The pricking is not deep but it will cause a sore spot and one or two droplets of blood to form. if the vaccination is successful a red and itchy bump develops at the vaccine site in 3 or 4 days. In the first week the bump becomes a large blister, fills with pus, and begins to drain. During the second week the blister begins to dry up and a scab forms. In the third week the scab falls off leaving a small scar. People who get the vaccine for the first time have a stronger reaction than those who are revaccinated.

Reactions and complications. The vaccine often causes fever as well as large skin reactions at the vaccination site. These reactions usually go away leaving only the telltate smallpox vaccine scar. The vaccine, however, can cause several complications, some life-threatening, particularly in people with immune deficiencies and skin disorders. Based on reactions to smallpox vaccines in the past CDC estimates that between 14 and 52 people out of every 1 million people vaccinated for the first time will have potentially life-threatening complications that require medical attention progressive Vaccinia uncontrolled spread of Vaccinia virus to adjacent and underlying tissues resulting in tissue death, postvaccinal encephalitis spread of the Vaccinia virus to the central nervous system that is probably made worse by an over-response by the immune system.

Vaccine supply and strength. Expanding the US smallpox vaccine supply is a high priority of the bioterrorism preparedness plan. Results from an NIAID study show that the existing US supply of smallpox vaccine 15.4 million doses could successfully be diluted up to five times and retain its potency effectively expanding the number of individuals it could protect from the contagious disease. The vaccine calledDryvax had been stored since production stopped in 1983.

The trial compared the full-strength vaccine with fivefold as well as tenfold dilutions in 680 young adults with no history of smallpox vaccination. More than 97 percent of all participants in the trial responded with a vaccine take, a blister-like sore at the injection site that serves as an indirect measure of the vaccine effectiveness. A new study has been conducted to determine how effective the diluted Dryvax is in the people who have been previously vaccinated against smallpox.

Treatment. In collaboration with the US Department of Defense (DoD) NIAID has screened more than 500 compounds against smallpox and related viruses. In addition, NIAID supports studies that evaluate experimental antiviral compounds in a number of mouse models in Vaccinia and cowpox (another member of the orthopoxvirus family). NIAID also supports mouse pox virus and rabbit pox virus models. Compounds that are effective in these small-animal models are given priority for evaluation by DoD researchers in the monkey pox primate model.

In addition to collaborating with DoD scientists, NIAID is working with scientists at other federal agencies such as CDC and the Department of Energy to develop and test at least three antiviral drugs against smallpox and determine whether existing antiviral compounds are those being developed are effective against variola virus. In addition to those treatment studies, NIAID is collaborating on studies to help develop a safer, sterile smallpox vaccine using modern technology; to explore developing a vaccine that can be used safely in all segments of the population; to increase scientific knowledge about the genome of Variola and related viruses.

ALLERGY

Allergy is not a disease in the typical sense. It is an exaggeration of the body’s natural immune defenses. Mild allergies can be annoying, and severe forms can be very serious or even deadly.

Allergies vary in the types of symptoms they cause and the methods to prevent and treat them. The type of allergy you have depends on the allergen that provokes your symptoms (such as mold or cat dander), the specific areas of the body affected by allergy symptoms (such as airways, skin or nose) and whether the reaction stays in one place or is triggered throughout the body. For example asthma, a type of allergy that may be triggered by a variety of airborne substances, is an exaggerated immune reaction confined to the airways of the lung. The symptoms of hay fever or seasonal allergies caused by pollen in the air are usually limited to the nose, eyes and sometimes the sinuses or the airways. On the other hand, an allergic reaction to an insect sting can trigger a severe response that affects the whole body. This response called anaphylaxis is potentially fatal.

Once you learn what type of allergy you have you can learn to prevent and treat it on your own. You can also learn how to recognize dangerous types of allergic reactions and when to get help.

General rules of allergy. Although each type of allergy behaves differently, some general rules apply:

1. Allergies always involve the immune system.

2. A reaction occurs after exposure to an allergen. The timing may be immediate – soon after contact with an allergen – or delayed – up to two contact (such as with poison ivy).

3. Prevention is just as important as treatment if not more.

The role of the immune system. All allergies are an immune reaction to a normally harmless antigen. An interesting quality of the immune system is that it is capable of learning. Each time you are exposed to an allergen, the immune system takes less time to react. Sometimes this reaction is more dramatic than the first, in some instances serious potentially life-threatening symptoms develop on subsequent exposure to an allergen.

Certain allergens are more likely to cause problems than others. It is important to avoid a second exposure if you have had a reaction in the past to insect stings, peanuts, latex or penicillin.

The role of the immune system in an allergy defines how that allergy is treated. All allergy treatments act by blocking immune system signals, such as histamines, or calming the immune system reaction (with corticosteroids).

The timing of the allergic reaction. Most allergic reactions occur shortly after you have been exposed to an allergen. For example, seasonal allergies are likely to worsen on the same day that the pollen count goes up. Or, if you have a cat allergy and visit the home of someone who owns a cat, you are likely to start developing an allergic reaction before you leave the house. However some allergic reaction take longer to occur. For example, some forms of contact dermatitis (such as poison ivy) may take more than a day or two to develop.

Prevention. Prevention is your best defense. Avoiding an allergen or treating your symptoms early is easier than trying to calm a reaction that has progressed out of control..

Common misconceptions about allergies. “All reactions to medications or foods are allergies”. There is a big difference between having an allergy to something versus an intolerance or side effects. People often use the term “allergy” loosely, referring to any reaction to medication or food as an allergy. Medication and food reactions can also be side effects or an intolerance (such as stomach or intestinal upset) rather than an allergy.

True allergies involve the immune system. Because immune system reactions can be dangerous or life threatening, it is extremely important to know if you have an allergy or an intolerance or side effects. Allergies to antibiotics such as penicillin or sulfa are often diagnosed by the appearance of a rash after taking the medication. If you take the medication a second time. The immune system reaction can be much more severe, even life threatening. On the other hand, an antibiotic such as erythromycin is commonly associated with stomach upset or diarrhea that is not related to the immune system. These symptoms are a side effect of this medication, not an allergic reaction. Because most symptoms from erythromycin are side effects, it is usually OK to take this medication or other related medications in the future. Always tell your doctor about any reactions to medications every time you are prescribed a medication.

“I am allergic to vaccines”. Another common misconception is that vaccines can cause allergic reactions. The site of vaccine injection can appear red, itchy or painful but this is usually the result of skin or muscle irritation or an infection at the injection site. The exceptions to this rule are vaccines that contain egg proteins. These vaccines can cause allergic reactions and should not be given to people with egg allergies.

The key to identifying true allergies is to give your health-care provider a precise description of your symptoms, including the amount of time between the reaction and the exposure to a specific medication, food or other medical treatment.

What causes allergies? Allergies result from a misfiring of the immune system which normally helps the body to fight off harmful viruses, bacteria and other microorganisms. In an allergic reaction the immune system perceives pollen, food or other allergens as a threat to health. The immune system defends against the invaders by creating antibodies that set off symptoms every time the allergenic substance enters your body or, in the case of a contact allergic reaction, touches your skin.

Common questions about allergies. Do children outgrow allergies? Food allergies to milk can be outgrown. On the other hand, children tend to keep allergies to peanuts, tree nuts, fish and shellfish into adulthood. If children do outgrow allergies it is often by age 3. Other allergy symptoms may improve as a child gets older nut new ones may develop.

Should a person move to another part of the country to escape the hay-fever season? Probably not. You could escape your current hay-fever symptoms by moving to another area but you could develop an allergy to a plant native to your new surroundings. Moving is usually not a practical solution to a pollen allergy.

Are allergies inherited? Yes. If one of your parents has a respiratory allergy like hay fever, you have a 30 to 50 percent chance of developing one, though not necessarily the same allergy. If both your parents have respiratory allergies, there’s a 60 percent to 80 percent likelihood that you will also develop an allergy.

Can breast-feeding prevent allergies? There’s no proof that breast-feeding protects the children of allergic parents from developing allergies at some point later in life but it could delay the onset of the allergies. Delaying the introduction of solid foods can further prolong the allergy-free period in babies who inherit a tendency toward allergy.

What is an anaphylactic reaction? Anaphylaxis is a severe, life-threatening allergic reaction – usually to foods, drugs or insect venom. The reaction can cause dizziness, breathing problems, an asthma attack, hives, a sudden drop in blood pressure or unconsciousness. If not treated promptly and correctly an anaphylactic reaction can be fatal. People at risk of these reactions should carry an emergency kit containing the drug epinephrine for use at the first sigh of symptoms.

How are allergies diagnosed? Your doctor may be able to diagnose an allergy on the basis of your symptoms and exposure to allergens. For instance, if you have allergy symptoms only during ragweed season, you probably are allergic to ragweed. If you have year-round symptoms, the problem could be dust mites, pet allergies or an allergy to a substance you come into contact with at work. You also may need some tests to identify the allergen. The simplest and most reliable is a skin test that scratches a drop of allergen extract into your skin. If you are allergic to the substance a reaction will develop within 15 minutes. A less accurate and more expensive blood test can be used when skin tests aren’t practical (if you have eczema or a skin condition that doesn’t permit testing) or would be dangerous (if you are severely allergic).

What is the most effective allergy treatment? Avoiding the substance that causes your allergy. This isn’t always possible if you have an allergy to common substances like pollen or dust mites, but you usually can reduce your exposure.

 

 

PNEUMONIA

What is pneumonia? Pneumonia is an infection of one or both lungs which is usually caused by bacteria, viruses, or fungi. Prior to the discovery of antibiotics one-third of all people who developed pneumonia subsequently died from the infection. Currently, over 3 million people develop pneumonia each year in the United States. Over half a million of these people are admitted to a hospital for treatment. Although most of these people recover approximately 5% will die from pneumonia. Pneumonia is the sixth leading cause of death in the United States.

How do people “catch” pneumonia? Some cases of pneumonia are contracted by breathing in small droplets that contain the organisms that can cause pneumonia. These droplets get into the air when a person infected with these germs coughs or sneezes. In other cases pneumonia is caused when bacteria or viruses that are normally present in the mouth, throat, or nose inadvertently enter the lung. During sleep it is quite common for people to aspirate secretions from the mouth, throat, or nose. Normally, the body reflex response (coughing back up the secretions) and immune system will prevent the aspirated organisms from causing pneumonia. However, if a person is in a weakened condition from another illness a severe pneumonia can develop. People with recent viral infections, lung disease, heart disease, and swallowing problems, as well as alcoholics, drug users, and those who have suffered a stroke or seizure are at higher risk for developing pneumonia than the general population.

Once organisms enter the lungs they usually settle in the air sacs of the lung where they rapidly grow in number. This area of the lung then becomes filled with fluid and pus as the body attempts to fight off the infection.

What are pneumonia symptoms and signs? Most people who develop pneumonia initially have symptoms of a cold which are then followed by a high fever (sometimes as high as 104 degrees F), shaking chills, and cough with sputum production. The sputum is usually discolored and sometimes bloody. People with pneumonia have become short of breath. The only pain fibers in the lung are on the surface of the lung in the area known as pleura. Chest pain may develop if the outer pleural aspects of the lung are involved. This pain is usually sharp and worsens when taking a deep breath known as pleuritic pain.

In other cases of pneumonia there can be a slow onset of symptoms. A worsening cough, headaches, and muscle aches may be the only symptoms. In some people with pneumonia coughing is not a major symptom because the infection is located in areas of the lung away from the larger airways. At times, the individual’s skin color may change and become dusky or purplish (a condition known as cyanosis) due to its blood being poorly oxygenated.

Children and babies who develop pneumonia often do not have any specific signs of chest infection but develop a fever, appear quite ill, and can become lethargic. Elderly people with pneumonia may also have few symptoms.

How is pneumonia diagnosed? Pneumonia may be suspected when a doctor examines a patient and hears coarse breathing or crackling sounds when listening to a portion of the chest with a stethoscope. There may be wheezing or the sounds of breathing may be faint in a particular area of the chest. A chest X-ray is usually ordered to confirm the diagnosis of pneumonia. The lungs have several segments referred to as lobes, usually two on the left and three on the right. When pneumonia affects one of these lobes it is often referred to as lobar pneumonia. Some pneumonias have a more patchy distribution that does not involve specific lobes. In the past, when both lungs were involved in the infection the term “double pneumonia” was used. This term is rarely used today.

Sputum samples can be collected and examined under the microscope. If pneumonia is caused by bacteria or fungi the organisms can often be detected by this examination. A sample of the sputum can be grown in special incubators and the offending organism can be subsequently identified. It is important to understand that the sputum specimen must contain little saliva from the mouth and be delivered to the laboratory fairly quickly. Otherwise, overgrowth of noninfecting bacteria may predominate.

A blood test that measures white blood cell count (WBC) may be performed. An individual’s WBC can often give a hint as to the severity of pneumonia and whether it is caused by bacteria or viruses. An increased number of neutrophils, one type of WBC, is seen in bacterial infections whereas an increase in lymphocytes, another type of WBC, is seen in viral infections.

Bronchoscopy is a procedure in which a thin, flexible, lighted viewing tube is inserted into the nose or mouth after a local anesthetic is administered. The breathing passages can then be directly examined by a doctor and specimens from the infected part of the lung can be obtained.

Pleural effusion. Sometimes fluid collects in the pleural space around the lung as a result of the inflammation from pneumonia.. This fluid is called pleural effusion. If the amount of this fluid that develops is large enough it can be removed by inserting a needle into the chest cavity and withdrawing the fluid with a syringe in a procedure called a thoracentesis. In some cases this fluid can become severely inflamed (parapneumonic effusion) or infected (empyema) and may need to be removed by more aggressive surgical procedures.

Conclusions. Pneumonia can be a serious life-threatening infection. This is true especially in the elderly, children, and those who have other serious medical problems such as chronic obstructive pulmonary disease (COPD), heart disease, diabetes, and certain cancers. Fortunately, with the discovery of many potent antibiotics most cases of pneumonia can be successfully treated. In fact, pneumonia can usually be treated with oral antibiotics without the need for hospitalization.

 

 

TUBERCULOSIS

Tuberculosis (TB) is an infectious disease caused by bacteria whose scientific mane is Mycobacterium tuberculosis. It was first isolated in 1882 by a German physician named Robert Koch who received the Nobel prize for this discovery. TB most commonly affects the lungs but also can involve almost any organ of the body. Many years ago this disease was referred to as “consumption” because without effective treatment these patients often would waste away. Today, of course, tuberculosis can usually be treated successfully with antibiotics.

There is also a group of organisms referred to as atypical tuberculosis. These involve other types of bacteria that are in the Mycobacterium family. Often these organisms do not cause disease and are referred to as “colonizers” because they simply live alongside other bacteria in out bodies without causing damage. At times, these bacteria can cause an infection that is sometimes clinically like typical tuberculosis. When these atypical mycobacteria cause infection they are often very difficult to be cured. Often drug therapy for these organisms must be administered for one and a half or two years and requires multiple medications.

How does a person get TB? A person can become infected with tuberculosis bacteria when he or she inhales minute particles of infected sputum from the air. The bacteria get into the air when someone who has a tuberculosis lung infection coughs, sneezes, shouts, or spits (which is common in some cultures). People who are nearby can then possibly breathe the bacteria into their lungs. You don’t get TB just touching the clothes or shaking hands of someone who is infected. Tuberculosis is spread (transmitted) primarily from person to person by breathing infected air during close contact.

There is a form of atypical tuberculosis, however, that is transmitted by drinking unpasteurized milk. Related bacteria called Mycobacterium bovis cause this form of TB. Previously, this type of bacteria was a major cause of TB in children but it rarely causes TB now since most milk is pasteurized (undergoes a heating process that kills the bacteria).

What happens to the body when a person gets TB? When the inhaled tuberculosis bacteria enter the lungs the can multiply and cause a local lung infection (pneumonia). The local lymph nodes associated with the lungs may also become involved with the infection and usually become enlarged. The hilar lymph nodes (the lymph nodes adjusted to the heart in the central part of the chest) are often involved.

In addition, TB can spread to other parts of the body. The body’s immune (defense) system, however, can fight off the infection and stop the bacteria from spreading. The immune system does so ultimately by forming scar tissue around the TB bacteria and isolating it from the rest of the body. Tuberculosis that occurs after initial exposure to the bacteria is often referred to as primary TB. If the body is able to form scar tissue (fibrosis) around the TB bacteria then the infection is contained in an inactive state. Such an individual typically has no symptoms and cannot spread TB to other people. The scar tissue and lymph nodes may eventually harden, like stone, due to the process of calcification of the scars (deposition of calcium from the bloodstream in the scar tissue). These scars often appear on X-rays and imaging studies like round marbles and are referred to as a granuloma. If these scars do not show any evidence of calcium on X-ray they can be difficult to be distinguished from cancer.

Sometimes, however, the body’s immune system becomes weakened and the TB bacteria break through the scar tissue and can cause active disease referred to as reactivation tuberculosis or secondary TB. Foe example, the immune system can be weakened by old age, the development of another infection or cancer, or certain medications used to treat arthritis or inflammatory bowel disease. The breakthrough of bacteria can result in a recurrence of pneumonia and a spread of TB to other locations in the body. The kidneys, bones, and lining of the brain an spinal cord (meninges) are the most common sites affected by the spread of Tb beyond the lungs.

How common is TB and who gets it? Over 8 million new cases of TB occur each year worldwide. In the United States it is estimated that 10-15 million people are infected with the TB bacteria and 22, 000 new cases of TB occur each year.

Anyone can get TB but certain people are at higher risk including those living with individuals who have an active TB infection, poor or homeless people, foreign-born people from countries that have a high prevalence of TB, nursing home residents and prison inmates, alcoholics and intravenous drug users, people with diabetes, certain cancers, and HIV infection (the AIDS virus), and health-care workers. There is no strong evidence for a genetically determined (inherited) susceptibility for TB.

What are the symptoms of TB? As previously mentioned, TB infection usually occurs initially in the upper part (lobe) of the lungs. The body’s immune system, however, can stop the bacteria from continuing to reproduce. Thus, the immune system can make the lung infection inactive (dormant). On the other hand, if the body’s immune system cannot contain the TB bacteria the bacteria will reproduce (become active or reactivate) in the lungs and spread elsewhere in the body.

It may take many months from the time the infection initially gets into the lungs until symptoms develop. The usual symptoms that occur with an active TB infection are a generalized tiredness or weakness, weight loss, fever, and night sweats. If the infection in the lung worsens then further symptoms can include coughing, chest pain, coughing with sputum (material from the lungs) and blood, and shortness of breath. If the infection spreads beyond the lungs the symptoms will depend upon the organs involved.

How does a doctor diagnose TB? Tuberculosis can be diagnosed in several different ways including chest X-rays, analysis of sputum, and skin tests. Sometimes, the chest X-rays can reveal the evidence of active tuberculosis pneumonia. Other times, the X-rays may show scarring (fibrosis) or hardening (calcification) in the lungs suggesting that TB is contained and inactive. Examination of the sputum on a slide (smear) under the microscope can show the presence of the tuberculosis-like bacteria. Bacteria of the mycobacterium family including atypical mycobacteria stain positive with special dyes and are referred to as acid-fast bacteria (AFB). A sample of the sputum is also usually taken and grown (cultured) in special incubators so that the tuberculosis bacteria can subsequently be identified as tuberculosis or atypical TB.

Several types of skin tests are used to screen for TB infection. These so-called tuberculin skin tests include the Tine test and the Mantoux test also known as the PPD (purified protein derivative) test. In each of these tests a small amount of purified extract from dead tuberculosis bacteria is injected under the skin. If a person is not infected with TB no reaction will occur at the site of the injection (a negative skin test). If a person is infected with tuberculosis, however, a raised and reddened area will occur around the site of the test injection. This reaction (a positive skin test) occurs about 48 to 72 hours after the injection.

 

ASTHMA

What is it? Asthma is a chronic lung condition with symptoms of difficulty breathing and wheezing caused by inflammation and narrowing of the air passages. The condition ranges from mild to severe. Some people have only occasional, mild symptoms while others have nearly constant symptoms with severe, life-threatening flare-ups.

During an asthma attack the airways become inflamed and narrower as the muscles surrounding them constrict. The flow of air is blocked partially or completely as mucus produced by the inflammation fills a narrower passageway. Asthma affects both the lungs larger airways called the bronchi and the lungs smaller airways called the bronchioles. Treatment focuses on preventing or stopping the inflammation and relaxing the muscles that line the airways.

What causes asthma-related inflammation is not clear but several environmental “triggers” have been identified. Many asthma triggers are allergens, substances that cause the immune system to overreact in some people. Common allergens include animal dander and saliva, pollens, molds, dust mites, cockroaches, some medications and certain foods. Also high on the list of asthma triggers are viral infections such as colds and influenza, exercise, breathing cold, dry air, environmental pollutants such as cigarette smoke, wood smoke, paint fumes and chemicals, strong odors, and emotional stress. For some people with severe asthma no specific triggers can be identified

Although asthma can develop early often before age 5, its symptoms can begin at any age. The condition has a genetic (inherited) component and often affects people with a family history of allergies. The American Lung Association estimates that 25 million people in the United States will be diagnosed with asthma in their lifetime. One-third of Americans with Asthma symptoms are children.

Symptoms. Symptoms of asthma include: wheezing (a whistling sound as air is forcibly expelled), difficulty breathing, chest tightness, a persistent cough.

For some people with asthma a chronic cough is the main symptom. For some people symptoms flare up only during or after exercise. Between asthma attacks or flare-ups people with mild or moderate asthma may have no symptoms at all. Asthma can lead to more severe cold or flu symptoms, or make a person more prone to bronchitis.

Symptoms of a severe asthma attack include: a rapid pulse, sweating, extreme shortness of breath, flared nostrils, using the chest and neck muscles during breathing, a bluish discoloration of the lips and fingernails (cyanosis).

Diagnosis. A thorough medical history is an important part of diagnosing and treating asthma. Your doctor will ask about any symptoms you have, how severe they are, when and where they occur, how frequently they occur, and what triggers and relieves them. These details will help your doctor find ways to prevent your asthma attacks. Your doctor will also want to know about your personal history of allergies and respiratory illnesses as well as your family history of asthma, allergies and respiratory illnesses.

Your doctor will listen to your back with a stethoscope to detect wheezing. During an attack your doctor can assess the severity of your flare-up by listening for the amount of airflow and by looking at how you are using your chest muscles to breathe. Blue lips or skin are a sign that you are not getting enough oxygen. Other tests that can be done in the office include a measurement of the speed of the air you can exhale forcibly done with a peak-flow meter. Another test measures oxygen levels in your blood and is done with a pulse oximeter, a small device that is placed on the tip of your finger.

During an asthma flare-up blood tests may be done to check for signs of an elevated white blood cell count which can indicate that you have an infection. A special test, called an arterial blood gas (ABG) can be done on blood drawn from your wrist to measure oxygen levels more accurately. Your doctor also may want you to have a chest X-ray.

Two tests show how well your lungs are functioning and can help to diagnose asthma and measure its severity: spirometry and peak-flow meter.

During spirometry you exhale into a device that analyzes the amount and volume of airflow. One part of the test may be repeated after you are given a medication called a bronchodilator that relaxes the muscles surrounding the airways to improve airflow. If airflow improves after use of a bronchodilator this helps to diagnose asthma. Sometimes a challenge test is performed, especially when spirometry appears normal. In this procedure you inhale a medication to see if it provokes a measurable contraction of the airway muscles (bronchospasm). People with asthma are more sensitive to this medication.

Peak-flow meter is a small portable tube measuring the speed of air expelled when you blow forcibly through it. These devices are often given to asthma patients for use at home to monitor their asthma and help to detect the earliest signs of an asthma flare-up.

There is no one test to diagnose asthma. Your doctor will rely on a combination of information from your history, physical exam and tests. If your symptoms are mild your doctor may prescribe an inhaler. If this relieves your symptoms your doctor can be sure you have asthma.

If your doctor suspects that your asthma is being triggered by allergens and the symptoms are not treated or controlled easily with medications a blood test or allergy skin testing may be performed. The blood test called the radioallergosorbent test (RAST) looks for antibodies to potential specific allergens. In allergy skin testing the skin is exposed to weak dilutions of different potential allergens either by pricking the skin with the allergen or using a patch taped to the skin for several days. If there is redness or swelling at the injection site an allergy to that substance is confirmed.

Expected duration. Asthma in adults is often a lifelong condition. But with treatment symptoms can be controlled and can be infrequent or very mild. In about half of children with asthma it can go away on its own or decrease in severity over time. However, it often reappears later in life.

Asthma episodes can go away on their own or with the help of asthma medications. Attacks vary in frequency and severity often dependent on which triggers cause the attack.

Prevention. In some cases asthma episodes can be prevented by avoiding or minimizing exposure to triggers. These include environmental triggers such as cigarette smoke, environmental pollutants (especially when pollution and ozone levels are high) and strong chemicals.

If exercise triggers your asthma you can prevent an attack by breathing warm, humidified air before and during exercise or by using inhalers. Preventive medicine also can be used before an anticipated exposure to animals.

Eliminating allergens at home often can go a long way to control asthma symptoms. Some people may need to avoid animals entirely or to take special measures with their pets such as keeping them out of bedrooms or bathing them regularly. If dust mites are a trigger some household anti-mite measures include encasing mattresses in airtight enclosures, frequent household cleaning, washing bedding frequently in very hot water, and removing carpets and heavy draperies from sleeping areas.

Those who are affected by pollens might stay indoors whenever possible, use air conditioning and keep windows closed during high pollen season.

Monitoring your symptoms and peak-flow readings helps to identify a coming attack hours or even days before symptoms develop which allows you to start treatment early. In many cases early treatment can stop an attack from occurring.

Early signs or symptoms of an asthma flare-up include: coughing more often, increased mucus or phlegm, becoming short of breath quickly with exertion or exercise, developing a sinus headache or fever, having symptoms that resemble a cold such as a runny or congested nose, sneezing or watery eyes.

Treatment. If you have chronic asthma you should work with your doctor to develop a written asthma-management plan. The plan specifies how to avoid asthma triggers, when and how regular medications should be taken, how to handle acute attacks, and how a peak-flow meter should be used. It is important that preventive asthma medications be taken as prescribed even when you are not having symptoms.

Several types of medication are available to treat asthma. Some treat acute attacks while others prevent attacks from happening.

1. Bronchodilators relax the muscles around the airways to improve airflow and they are commonly inhaled. One class of bronchodilators called beta agonists including albuterol typically can be prescribed alone for mild occasional symptoms. Albuterol also is used as a “rescue “ medication to stop an attack. It can be inhaled in an inhaler or taken with a nebulizer, a device that mixes medications with a mist for inhalation. Other bronchodilators including salmeterol and theophylline (sold under numerous brand names) are used to prevent and control asthma. They are not useful for an asthma attack because they take too long to begin working.

2. Anti-inflammatory medications usually are taken regularly to prevent asthma attacks from occurring. These drugs work by reducing inflammation and reducing constriction of airway muscles. Steroid medications inhaled or taken orally reduce inflammation and are used to treat moderate or severe disease. People with moderate disease often can control their asthma quite well by using a steroid inhaler. Oral or intravenous steroids are given in higher doses to serve as a rescue-type medication and then tapered off over several days to weeks. Cromolyn sodium and nedocromil are anti-inflammatories that can help prevent attacks in mild to moderate asthma if used daily. They also can be used before contact with a known asthma trigger, for example, before exercise or exposure to animals. Leukotriene modifiers are the new type of anti-inflammatory medication. Taken orally these drugs block leukotrienes, one of the many chemicals that cause inflammation and airway narrowing in many people with asthma.

Some people with asthma also benefit from immunotherapy in which the person is injected with increasing amounts of allergens to desensitize the person’s immune system. Immunotherapy for asthma appears to be most effective for mild to moderate symptoms that are caused by sensitivity to indoor allergens such as dust mites, mold spores and animals.

Severe asthma attacks must be treated in a hospital where oxygen can be administered and drugs may be given either intravenously or with a nebulizer. In life-threatening cases the patient may require intubation (placing a breathing tube in the large airway) and artificial ventilation in an intensive care unit.

When to call a professional. Call your doctor whenever you or your child has persistent wheezing, chest tightness, difficulty with breathing or cough. Some children with asthma may not complain specially of shortness of breath. However, they may flare their nostrils or use their chest and neck muscles when breathing – signs that they are having trouble.

If you already have been diagnosed with asthma call your doctor if your symptoms are worsening or are not being controlled by your regular medications. For example, you should call your doctor if you must use your rescue inhaled bronchodilator more than four times a day to control symptoms or your peak-flow-meter readings are in the yellow or red zones.

If you have an asthma attack and your symptoms persist despite your medications, seek emergency help immediately.

Prognosis. Although asthma cannot be cured it almost always can be controlled successfully. Most people who have asthma can expect to lead relatively normal lives.

Facts about asthma. if you have asthma you’re already familiar with its chest-clutching, short-of-breath feeling. If you don’t have asthma but want to know what it feels like, try this: take two of those little straws that people use to stir coffee or tea. Clamp your lips tightly around them and hold your nose. Now breathe. Feel how hard your lungs work to get air in and out? Or how quickly you get short of breath? That’s full-blown asthma.

Of course, there are milder examples of symptoms such as a whistle or wheeze when you breathe a tightness in your chest or a nagging cough. But all asthma symptoms stem from the same problem – you are breathing through smaller straws in your lungs.

This chronic disease has several types. What makes them different are the triggers, the things that set asthma off. For sвовремяome people the trigger is an allergy to cats or to mold. Exercise can be a trigger as can chemicals in the air, cigarette smoke or a cold or the flu. Some triggers are so stealthy that some people are never able to identify them.

No matter what the trigger is, the end result is always the same – the airways tighten up and narrow, making it hard to move air in and out of the lungs. The whistle or wheeze you can sometimes hear when someone with asthma breathes is the sound of air rushing through these constricted airways and blocked air sacs in the lungs.

Misconceptions about asthma. Asthma is shrouded in mystery and misconception. The mystery reflects the ingoing efforts of scientists to understand this disease better. The misconception represents outdated or overly dramatic images of asthma. If you’ve ever read Lord of the Flies or seen the movie you might remember Piggy, the pudgy, bespectacled boy who can’t keep up with the pack because of his asthma. Perhaps you’ve seen a TV program that shows someone with asthma suddenly start to wheeze and then use an inhaler for immediate resolution. Or maybe you’ve heard that asthma is mostly a childhood disease that may outgrow.

Recent advances have put a new face on asthma. Scientists have shown that this condition is caused by inflammation, the same process that makes a sprained ankle swell. Preventing inflammation by avoiding the things that trigger it and/ or by blocking it with drugs can help people with asthma to have relatively mild symptoms and few, if any, full-blown asthma attacks. New drugs that target inflammation – some delivered by inhalers, some in pill form – can ease asthma symptoms and help to limit the side effects in older drugs such as heart palpitations and nausea.

Overall, the goal of managing and treating asthma is to make it easier for you to lead a normal, healthy life. Managing your asthma even when you don’t have symptoms will help keep you out of the emergency room and minimize long-term damage to your lungs.

Causes and triggers of asthma: understanding inflammation. Unfortunately, medical researchers don’t know exactly what causes asthma. It’s entirely possible that no single cause will ever be found. What health-care professionals do know is that people with asthma have trouble breathing because the tubes that carry air to from the lungs (that is the airways) become inflamed. Inflammation causes mucus to build up in these tubes cutting down on the space available to move air. Inflammation also stimulates the muscles around these tubes to contract narrowing the tubes and further cutting down the air flow. Although inflammation is the root of all asthma, the trigger for this inflammation is different for different people.

Understanding how inflammation causes asthma will bring you one step closer to controlling this disease. That’s because stopping or preventing inflammation by avoiding the things that trigger it is key to keeping the airways open which promotes good airflow and comfortable breathing. Understanding the role that inflammation plays also will help you to understand why you may need to take at least two different drugs – one to control or prevent inflammation and another to open constricted airways.

Unraveling asthma link to inflammation has led to huge advances in treating this disease. This work has laid the groundwork for new classes of drugs aimed at controlling or preventing airway inflammation. These new drugs work hand in hand with the old and still important standbys – drugs that relax and open the airway,

The how and why of inflammation. Inflammation is an important part of your body’s response to injury or infection. Basically, inflammation is the immune system call to action. Signals sent by the immune system recruit an army of cells to fight off invaders such as bacteria or viruses. They also start the healing process when there are signs of tissue damage. For example, when you scrape a knee on a dirty sidewalk bacteria cling to the wounded tissue. “Scout” cells sense these foreigners and send chemical signals that attract other cells to this spot. These new arrivals release substances that attract still more cells that help clean the wound and draw more body fluid to it. This is why the area becomes swollen.

In people with asthma the lungs and airways overreact to foreign substances in the air such as cat hair, mold, or pollution. Sometimes even clean, cold air can constrict the airways especially in people with exercise-induced asthma. In many ways asthma is a type of allergic reaction that is why many people with asthma also see an allergy specialist to help manage their condition.

 

 

BLOOD PRESSURE

Blood pressure allows to flow and deliver nutrients to the body. We measure blood pressure with two numbers. The top number is the blood pressure when your heart beats. The bottom number is your blood when your heart relaxes and refills with blood. The higher your numbers and the longer they are high, the more damage is caused to your blood vessels.

Blood pressure increases with age. More than nine in ten Canadiens will develop high blood pressure (hypertension) unless they follow a healthy lifestyle. High blood pressure is the leading risk for death. High blood pressure can cause strokes, heart attacks, and heart and kidney failure. It is also related to dementia and sexual problems. These problems can be prevented if high blood pressure is controlled.

Leading risks for death in North America. You may not experience any symptoms if you have high blood pressure so you should have your blood pressure measured regularly throughout your life. Remember, even if you are young you could still have high blood pressure so get your blood pressure checked.

One high blood pressure reading does not necessarily mean you have hypertension. Your doctor may diagnose hypertension right away if your blood pressure is extremely high or may ask you to come back for several visits before a diagnosis can be made.

Blood pressure should be measured when you are relaxed and rested because most people Have higher readings when they are under physical or emotional stress. Monitoring your own blood pressure with a home blood pressure monitor can be helpful.

If you have high blood pressure. Have your blood pressure measured regularly. See a doctor regularly. Have your cholesterol measured. Most people with high blood pressure have other risks for heart disease and stroke such as high cholesterol. Have your blood sugar checked. people with diabetes and high blood pressure must be monitored closely and need to strive for lower blood pressure targets. have your kidney function checked. This can be done by measuring the salts in your blood and by testing your urine. Kidney problems can cause high blood pressure. If you are told you have high blood pressure tell your family members. They may be at risk for hypertension and should have their blood pressure checked.

Measurements. It is important to have your blood pressure measured regularly and know your blood pressure numbers. Both numbers are important. We measure blood pressure with two numbers. The top number is the systolic blood pressure and is the largest number. This is the pressure in your blood vessels when your heart beats and pumps blood. The bottom number is the diastolic blood pressure. This is the pressure in your blood vessels when your heart relaxes and fills with blood. The higher your systolic or diastolic pressure is and the longer these numbers are high> the more damage occurs to your blood vessels. Strokes and heart attacks are caused by damaged blood vessels.

Regular blood pressure monitoring is especially important if your blood pressure is between 130/85 and 139/89. This is called “high normal” blood pressure. More than half of people with “high normal” blood pressure develop hypertension within four years unless they make lifestyle changes.

What is “white coat” hypertension. Some people have high blood pressure when they visit a doctor’s office but have normal blood pressure otherwise. This condition is called “white coat” hypertension. If your doctor thinks you have “white coat” hypertension you may be asked to monitor your blood pressure at home or wear an ambulatory blood pressure monitor. An ambulatory blood pressure monitor is a small machine, about the size of a portable radio that you wear on your belt for 24 hours. This machine lets your doctor find out what your blood pressure was every 15 to 30 minutes. This information can help you and your doctor see the changes in your blood pressure during a normal day. Most people with “white coat” hypertension are not at higher risk of health problems but they do require regular monitoring as they are more likely to develop true hypertension over time.

Masked hypertension. Masked hypertension is the opposite of “white coat” hypertension. People with this condition have normal blood pressure in a doctor’s office but have high blood pressure when elsewhere. If your doctor thinks you have masked hypertension you may be asked to monitor your blood pressure at home or wear an pressure.


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