Fact Sheet - Chronic Fatigue Syndrome

Chronic Fatigue Syndrome

What Is Chronic Fatigue Syndrome?

We all get hold of tired. Many of us at times have feel depressed. But the mystery known as chronic fatigue syndrome (CFS) is not similar to the normal al ups and downs we experience surrounded by everyday life. The precipitate sign of this illness is a strong and traceable fatigue that comes on suddenly and often comes and go or never stops. You feel too tired to do regular activities or are well exhausted with no adjectives reason. Unlike the mind fog of a serious hangover, to which researchers hold compared CFS, the profound weakness of CFS does not run away with a few accurate nights of sleep. Instead, it slyly steals your perkiness and vigor over months and sometimes years.

How CFS Begins and Its Symptoms

For many culture, CFS begins after a bout next to a cold, bronchitis, hepatitis, or an intestinal bug. For some, it follows a bout of infectious mononucleosis, or mono, which temporarily saps the get-up-and-go of many teenagers and infantile adults. Often, people influence that their illnesses started during a period of large stress. In others, CFS develops more gradually, next to no clear illness or other event starting it.

Unlike flu symptoms, which usually step away in a few days or weeks, CFS symptoms any hang on or come and budge frequently for more than six months. CFS symptoms include:

* Headache

* Tender lymph nodes

* Fatigue and weakness

* Muscle and joint aches

* Inability to concentrate

Who Gets CFS?

CFS be once stereotyped as a new "yuppie flu" because those who sought facilitate for and caused solid interest in CFS in the early 1980s be mainly well-educated, well-off women within their thirties and forties. Similar illnesses, known by different name, however, date back at lowest possible to the late 1800s. The modern stereotype arose. Since after, doctors have see the syndrome in associates of all ages, race, and social and economic classes from several countries around the world.

Still, CFS is diagnosed two to four times more normally in women than surrounded by men, possibly because of biological, psychological, and social influences. For example,

* CFS may have a femininity difference similar to diseases such as systemic lupus erythematosus and multiple sclerosis, which affect more women than men.

* Women may be more likely than men to settle with their doctors around CFS-like symptoms.

* Some members of the medical community and the public do not know in the order of or are skeptical of the syndrome.

* An increasingly diverse patient group will possible emerge as more doctors see CFS as a real disorder.

How Many People Have It?

Because near is no specific laboratory test or clinical sign for CFS, not a soul knows how frequent people this condition affects. CDC estimates, however, that as many as 500,000 population in the United States hold a CFS-like condition.

What Causes CFS?

While no one know what causes CFS, for more than a century, doctors hold reported seeing illnesses similar to it. In the 1860s, Dr. George Beard named the syndrome neurasthenia because he thought it be a nervous disorder near weakness and fatigue. Since next, health experts enjoy suggested other explanations for this baffling illness:

* Iron-poor blood (anemia),

* Low blood sugar (hypoglycemia),

* Environmental allergy, or

* A body far-reaching yeast infection (candidiasis).

In the mid-1980s, the illness become labeled "chronic EBV" when laboratory clues led scientists to wonder whether the Epstein-Barr virus (EBV) might be causing this group of symptoms. New evidence soon strike doubt on the theory that EBV could be the singular thing cause CFS. High levels of EBV antibodies (disease-fighting proteins) enjoy now be found in some strong people as okay as in some individuals with CFS. Likewise, some populace who don't have EBV antibodies, and who thus hold never been infected near the virus, can show CFS symptoms.

How Is CFS Diagnosed?

Doctors find it difficult to diagnose CFS because it has matching symptoms as many other diseases. When conversation with and examining you, your doctor must first rule out diseases that look similar, such as multiple sclerosis and systemic lupus erythematosus where symptoms can take years to develop. In follow-up visit, you and your doctor need to be alert to any clean cues or symptoms that might show that the problem is something other than CFS.

When other diseases are ruled out and if your complaint meets other criteria as powerfully, your doctor can diagnose you with CFS (see The CFS Case Definition).

The CFS Case Definition

The EBV work sparked trial interest in the syndrome among a small group of medical researchers. They realized they needed a standard method to describe CFS so that they could more easily compare research results.

In the behind time 1980s, CDC brought together a group of CFS experts to tackle this problem. Based on the best information available at the time, this group published in the March 1988 issue of the quantifiable journal, Annals of Internal Medicine, strict symptom and physical criteria - the first baggage definition - by which scientists could evaluate CFS study patients.

Not knowing the cause or a specific sign for the disease, the group agreed to phone the illness "chronic fatigue syndrome" after its primary symptom. "Syndrome" method a group of symptoms that occur together but can result from different cause. (Today, CFS also is known as myalgic encephalomyelitis, postviral fatigue syndrome, and chronic fatigue and immune dysfunction syndrome.)

After using this definition for several years, CFS researchers realize some criteria were blurry or redundant. An international group of CFS experts reviewed the criteria for CDC, which led to the first change in the baggage definition. This new definition be published in matching journal contained by December 1994.

Besides revising the CFS case criteria - which reduced the required minimum number of symptoms to four out of a detail of eight possible symptoms - the newer report also proposed a conceptual outline for studying the syndrome. This outline recognizes CFS as part of the pack of a range of illnesses that enjoy fatigue as a major symptom. Although primarily intended for researchers, these guidelines should give a hand doctors better diagnose CFS.

How Can I Cope With and Manage the Illness?

There is no effective treatment for CFS. Even though within is no specific treatment for CFS itself, you may find it quite cooperative to treat your symptoms. Nonsteroidal anti-inflmnmatory drugs, such as ibuprofen, may help find rid of any body aches or disorientation, and nonsedating antihistamines may help relieve any prominent allergic symptoms, such as numy antenna.

Learning how to manage your fatigue may serve you improve the height at which you can function and your quality of enthusiasm despite your symptoms. A rehabilitation medicine specialist can evaluate and inculcate you how to plan activities to cart advantage of times when you usually be aware of better.

The lack of any proven influential treatment can be frustrating to both you and your doctors. If you have CFS, condition experts recommend that you try to maintain dutiful health by:

* Eating a suspended diet and getting adequate rest.

* Exercising regularly but in need causing more fatigue.

* Pacing yourself - physically, emotionally, and intellectually - since too much stress can aggravate your symptoms.

The course of CFS vary from patient to forgiving. For most people, CFS symptoms plateau hasty in the course of sickness and thereafter wax and wane. Some people bring better completely, but it is not clear how frequently this happens. Emotional support and counseling can oblige you and your loved ones cope with the unconvinced outlook and the ups and downs of this illness.

Although spanking new studies seem to show that cognitive behavioral dream therapy and graduated exercise programs can greatly give support to many. Others are help by antidepressants.

Because well-designed clinical studies have found that patients near fibromyalgia (an illness similar to CFS) benefit from low-dose tricyclic antidepressants, doctors repeatedly prescribe these drugs for people near CFS with largely positive results. Some researchers believe that these drugs improve the element of sleep. Patients also have benefited from other kind of antidepressants, including the newer serotonin reuptake inhibitors. Therapeutic doses of antidepressants often increase fatigue in CFS, so doctors may enjoy to increase the dosage very slowly, or prescribe more stirring antidepressants. In addition, some race with CFS benefit from the benzodiazepines, a class of drugs used to treat acute anxiety and sleep problems. Patients commonly try more than one drug before finding one that works and can be tolerated.

Conclusion

CFS seem to involve interactions between the immune and central like a cat on a hot tin roof systems, interactions about which scientists know relatively little. Scientists' concerted pains to penetrate the complex frightened system and immune system events in CFS own created a challenging contemporary concept of the pathology of this and other illnesses.

For More Information About CFS, Contact:

Centers for Disease Control and Prevention 1500 Clifton Road NE Atlanta, GA 30333 1-800-232-3228 www.cdc.gov/ncidod/diseases/cfs/facts.htm

NIAID is a component of the National Institutes of Health (NIH). NIAID supports basic and applied research to prevent, diagnose, and treat infectious and immune-mediated illnesses, including HIV/AIDS and other sexually transmitted diseases, tuberculosis, malaria, autoimmune disorders, asthma and allergies.

Prepared by: Office of Communications and Public Liaison National Institute of Allergy and Infectious Diseases National Institutes of Health Bethesda, MD 20892

Public Health Service U.S. Department of Health and Human Services November 2000

Publications Home Centers for Disease Control and Prevention Chronic Fatigue Syndrome (CFS) Page

Flu

Influenza, or the flu, is a respiratory infection cause by a variety of flu virus. The most familiar aspect of the flu is the agency it can "knock you off your foot" as it sweeps through entire communities.

The flu differs in several ways from the adjectives cold, a respiratory infection also caused by virus. For example, people next to colds rarely bring fevers or headache or suffer from the extreme exhaustion that flu virus cause.

The U.S. Centers for Disease Control and Prevention (CDC) estimates that 35 to 50 million Americans come down next to the flu during each flu season, which typically last from November to March. Children are two to three times more likely than adults to go and get sick with the flu, and children frequently spread the virus to others. Although most citizens recover from the disease, CDC estimates that in the United States more that 100,000 general public are hospitalized and more than 20,000 people die from the flu and its complications every year.

When and Where Do People Usually Get the Flu?

Flu outbreaks usually start off suddenly and occur in principal in the behind fall and winter. The disease spreads through communities creating an epidemic. During the epidemic, the number of cases peak in in the order of three weeks and subsides after another three or four weeks. Half of the population of a community may be affected. Because school are an excellent place for flu viruses to attack and spread, family with school-age children own more infections than other families, beside an average of one-third of the family member infected each year.

Is the Flu an Important Disease?

Besides the fast start of the outbreaks and the large numbers of populace affected, the flu is an vital disease because it can cause serious complications. Most people who return with the flu get better in a week (although they may have a poignant cough and tire easily for a while longer). For elderly citizens, newborn babies, and people next to certain chronic illnesses, however, the flu and its complications can be life-threatening.

How is the Flu Transmitted?

You can capture the flu if someone around you who has the flu coughs or sneezes. You can seize the flu simply by touching a surface like a receiver or door knob that has be contaminated by a touch from someone who has the flu. The virus can pass through the heavens and can enter your body through your nose or mouth. If you've touched a contaminated surface, they can pass by from your hand to your muzzle or mouth.

You are at greatest risk of getting infected in highly populated areas, such as within crowded living conditions and in schools.

What are Flu Symptoms?

If you obtain infected by the flu virus, you will usually feel symptoms one to four days subsequently. You can spread the flu to others before your symptoms start and for another three to four days after your symptoms appear. The symptoms start greatly quickly and are

* Headache

* Chills

* Dry cough

* Body aches

* Fever

* Stuffy nose

* Sore throat

Typically, the disorientation begins to decline on the second or third daytime of the illness. The flu almost never cause symptoms in the stomach and intestines. The ailment that some people normally call "stomach flu" is not influenza.

How Does a Doctor Diagnose the Flu?

Usually, doctors or other condition care workers diagnose the flu on the reason of whether flu is epidemic in the community and whether the forgiving's complaints fit the current pattern of symptoms. Doctors once in a blue moon use laboratory tests to identify the virus during an epidemic. Health official, however, monitor certain U.S. form clinics and do laboratory tests to determine which type of flu virus is responsible for the epidemic.

How Can I Keep from Getting the Flu?

Flu Vaccine

The principal way to hold from getting the flu is to get a yearly flu vaccine. You can carry the vaccine at your doctor's office or a local clinic, and in heaps communities at work places, supermarkets, and drugstores. You must get the vaccine every year because it change.

Scientists make a different vaccine every year because the strains of flu virus change from year to year. Nine to 10 months back the flu season begins, they prepare a brand new vaccine made from inactivated (killed) flu viruses. Because the virus are killed, they cannot make happen infections. The vaccine preparation is based on the strains of the flu virus that are in circulation at the time. It includes those A and B virus (see section below on types of flu viruses) expected to circulate the following winter.

Sometimes, an unpredicted tentative strain may appear after the vaccine has be made and distributed to doctors and clinics. Because of this, even if you do get the flu vaccine, you still may receive infected. If you do get infected, however, the disease usually is milder because the vaccine still will hand over you some protection.

Your immune system takes time to respond to the flu vaccine. Therefore, you should take vaccinated six to eight weeks past flu season begins to prevent getting infected or eat up the severity of flu if you do get it. The vaccine itself cannot lead to the flu, but you could become exposed to the virus by someone else and get infected soon after you are vaccinate.

Are there possible side effects from the flu vaccine?

You should be aware that the flu vaccine can produce side effects. The most common side effect within children and adults is soreness at the site of the vaccination. Other side effects, especially contained by children who previously have not be exposed to the flu virus, include fever, tiredness, and sore muscles. These side effects may start off 6 to 1.2 hours after vaccination and may ending for up to two days.

Viruses for producing the vaccine are grown in chicken eggs and then kill with a chemical so that they can no longer create an infection. The flu vaccine may contain some egg protein, which can cause an allergic impulse. Therefore, if you are allergic to eggs or have ever have a serious allergic reaction to the flu vaccine, CDC recommend that you consult with your doctor beforehand getting vaccinated.

Who should bring back the flu vaccine?

If you are in any of the following groups or live in a household with someone who is, CDC recommend that you get the flu vaccine.

* You are 50 years of age or elder.

* You have chronic diseases of your heart, lungs, or kidneys.

* You enjoy diabetes.

* Your immune system does not function properly.

* You have a severe from of anemia.

* You will be more than three months pregnant during the flu season.

* You live in a nursing home or other chronic-care housing facility.

Children should bring back the flu vaccine if they are taking long-term aspirin treatment as they may be at risk of developing Reye's syndrome following a flu infection (see section on complications within children). They should also get the flu vaccine if they live in a household near someone in the above groups.

Health vigilance workers and volunteers should get the flu vaccine if they work near patients in any of the above groups.

Medicine for Prevention

Although the flu vaccine is the best approach to prevent getting the flu, three antiviral medicines also are available by prescription that will relief prevent flu infection:

* Tamiflu[R] (oseltamivir)

* Flumadine[R] (rimantadine)

* Symmetrel[R] (amantadine)

The Food and Drug Administration (FDA) has approved Tamiflu[R] for use surrounded by adults and adolescents 13 years and older. Rimantadine and amantadine own been approved for use by adults and children who are 1 year of age and elder.

Rimantadine and amantadine have unpleasant side effects. Your doctor can back you decide which drug is best for you.

* These medicines assist prevent the flu if you take them for at most minuscule two weeks during the outbreak of flu in your community.

* You may use these medicines if you are contained by close contact with ethnic group members or others who own the flu.

* You may use them if you are in close contact near people who enjoy been vaccinate but whom you want to give added protection from getting the flu.

* You may use any medicine instantly following flu vaccination during a flu epidemic to protect you during the two- to four-week term before antibodies (proteins from your immune system that protect you from the flu virus) develop or when a flu epidemic is cause by virus strains other than those covered by the vaccine.

You should discuss the flu vaccine and the medicine with your doctor beforehand the flu season begins.

What is the Treatment for the Flu?

Many population treat their flu infections by simply

* Resting in bed

* Drinking plenty of fluids

* Taking over-the-counter medicine such as aspirin or acetaminophen (Tylenol[R], for example)

You should not donate aspirin to children and adolescents who have the flu.

You should not embezzle antibiotics to treat the flu because they do not work on viruses. Antibiotics simply work against some infections caused by germs.

Medicine for Treatment

If you do get the flu and want to whip medicine to treat it, your doctor may prescribe one of four available antiviral medicine:

* Tamiflu[R] (oseltamivir) helps adults 18 years and elder and Relenza[R] (zanamivir) helps adults and children 7 years and elder who have an uncomplicated flu infection and who enjoy had symptoms for no more than two days. FDA lately approved Tamiflu[R] for use in children 1 year of age and elder who have have symptoms for no more than two days. Both treat influenza type A and type B infections.

* Flumadine[R] (rimantadine) helps adults who hold influenza type A virus infections. It has no effect on influenza type B virus infections.

* Symmetrel[R] (amantadine) can be taken by adults and children who are 1 year of age and elder to prevent and treat type A or type B influenza virus infections. Amantadine, however, is more likely to produce side effects such as lightheadedness and inability to sleep more often than is rimantadine.

To work ably, you must take these medicine within 48 hours after the flu begin. They reduce the length or time frenzy and other symptoms last and allow you to return to your day by day routine quicker. What are Possible Complications from the Flu?

You can have flu complications if you win a bacterial infection, which causes pneumonia within your weakened lungs. Pneumonia also can be cause by the flu virus itself.

Symptoms of complications will usually appear after you start feeling better. After a brief interval of improvement, you may suddenly get

* High fever

* Shaking chills

* Chest dull pain with respectively breath

* Coughing that produces thick, yellow-greenish-colored mucus

Pneumonia can be a highly serious and sometimes life-threatening condition. If you have any of these symptoms, you should contact your doctor irmnediately so that you can bring the appropriate treatment.

Are There Other Flu Complications that Only Affect Children?

Reye's syndrome, a condition that affects the nerves, sometimes develops in children and adolescents who are recovering from the flu. Reye's syndrome begin with nausea and vomiting, but the progressive mental change (such as confusion or delirium) cause the greatest concern.

The syndrome regularly begins contained by young ethnic group after they take aspirin to take rid of fever or discomfort. Although very few children develop Reye's syndrome, you should consult a doctor previously giving aspirin or products that contain aspirin to children. Acetaminophen does not seem to be associated beside Reye's syndrome.

Other complications of the flu that affect children are

* Convulsions caused by fever

* Croup

* Ear infections, such as otitis media

Newborn babies only just out of intensive care unit are particularly adjectives to suffering from flu complications.

Are There Different Types of Flu Viruses?

The first flu virus was identified within the 1930's. Since then, scientists hold classified flu viruses into types A, B, and C.

Type A is the most adjectives and usually causes the most serious epidemics. Type B outbreaks also can explanation epidemics, but the disease it produces generally is milder than that cause by type A. Type C viruses, instead, never have be connected with a roomy epidemic.

Flu Pandemics in the 20th Century

If a flu virus emerge that is any new or that have not circulated in masses years, and if it is able to spread slickly from person to being, it could quickly travel around the world and produce serious illness and departure for millions of people. This is call a flu pandemic.

The 1918 Spanish flu pandemic is the catastrophe against which adjectives modern pandemics are measured. More than 20 million people be killed worldwide; 500,000 died within the United States alone. This virus was especially hurried to kill. So far, the world have not seen a virus that severe again.

In 1957 and 1968, the Asian flu and Hong Kong flu, respectively, invaded the United States. Although hundreds of thousands of inhabitants in the United States died, the departure toll for each pandemic be not as high as that for the Spanish flu.

In 1976, the United States experienced a swine flu alarm. When a new flu virus be first identified at Fort Dix, New Jersey, it was labeled the "assassin flu," and health experts be afraid that it would infect people around the world. In certainty, swine flu never left the Fort Dix nouns. Research on the virus later showed that if it have spread, it would probably have be much less deep than the Spanish flu.

In 1997, another "near miss" pandemic occur when 18 people contained by Hong Kong became off-colour from a new flu virus. Six of the infected general public subsequently died. Usually, flu viruses move first from chickens to pigs, and later from pigs to humans. This virus was different because it moved directly from chickens to ethnic group. The avian flu never became a pandemic, however, because it didn't well spread from person to party. In addition, public form authorities ordered the slaughter of all live chickens contained by Hong Kong.

What Research is Going On?

Although flu epidemics pop up in the fall and winter season in communities throughout the world every year, including the United States, in attendance has not be a pandemic since 1968. Scientists are worried that a new flu virus will emerge within the 21st century and cause a severe pandemic again. For this basis, research institutions and health departments around the world are cooperating to track flu outbreaks in humans and animals, and to determine what types and strains of flu virus are the causes.

To prevent another flu pandemic and diminish the numbers of flu epidemics, the National Institute of Allergy and Infectious Diseases (NIAID) supports research to find out how influenza viruses work, and to develop better vaccines to prevent and treat influenza virus infections.

For the first time, NIAID-supported researchers enjoy built a flu virus from scratch. They made copies of a live influenza A virus by starting next to its individual nucleic acid building blocks. Nucleic acids contain the virus's genetic blueprint. By allowing researchers to press influenza viruses and produce mutations at will, the virus can be engineered to game exactly the strains that may be circulating in the coming season. This research has far-ranging implication for preventing flu and other infectious diseases, for gene therapy, and for command the ways flu strains mutate, spread, and cause comprehensive sickness and death.

Researchers supported by NIAID discovered why some influenza virus are more deadly than others. They found an unusual molecular workings that amplifies the disease-causing power of influenza A virus. This mechanism could be a alien marker for scientists to examine when attempting to predict the potential for a not long emergent influenza A virus to cause a pandemic.

In another research study, scientists supported by NIAID found that an investigational flu vaccine sprayed as a fine mist into children's nostrils is notably effective within preventing both the flu and otitis media, a adjectives flu-related ear infection. If doctors give this vaccine to children routinely, the number of flu cases in children could shrink substantially. In addition, if the cases of ear infection near fever are reduced, children would enjoy to take antibiotics smaller quantity often.

A current NIAID program encourages private companies to draw from involved in influenza research. Through its Challenge Grants Program, NIAID gave similar funds to companies who were likely to commit their own dollars and resources toward developing new vaccines against several infectious diseases, including the flu.

In one of these studies, Aviron will try to develop a powerless live influenza virus vaccine and will study new ways to produce vaccines against adjectives worldwide outbreaks (pandemics) of the flu. They will also work on a vaccine that can be given as a nasal mist instead of a shot, making it a promising option for rife use.

Scientists at Aventis Pasteur hope to produce four new vaccines that will shorten the response time needed to produce vaccines against pandemic influenza virus.

Currently, influenza vaccines are produced by growing the virus in chicken eggs. Egg proteins, however, cause allergic reaction in some those. Moreover, eggs may be in short supply during a pandemic. For these reason, Novavax is studying ways to produce several influenza vaccines without growing them in eggs.