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Legionnaires' Disease
Sick building syndrome facts
- Sick building syndrome is believed by some to be an illness caused by unknown agents in buildings.
- Sick building syndrome is a controversial subject because many experts do not think it is a true syndrome.
- Sick building syndrome has no known cause, however, known causes of illness such as lead poisoning, formaldehyde fumes, and many others have been associated with individual buildings.
- For those who believe the syndrome is real, many risk factors are cited.
- Many nonspecific symptoms cited for the syndrome fit no pattern.
- There are no diagnostic tests for the syndrome.
- There is no specific treatment for the syndrome.
- Complications of the alleged syndrome range from increased symptoms to inability to tolerate being inside a certain building and the problems, many job related, that may occur.
- The prognosis of an alleged syndrome is unclear, but symptomatic treatments may reduce problems and result in a fair to good prognosis -- so may treatment of known causes of building-related problems like formaldehyde and paint fumes and many others.
- Prevention is difficult in a syndrome without a known cause, no diagnostic tests, and no defined treatments, but the Environmental Protection Agency provides prevention methods to address known disease problems that can be diagnosed and are known to be related to air-moving systems and construction materials used in buildings.
What is sick building syndrome?
Sick building syndrome (also termed environmental illness, building-related illness [BRI], or multiple chemical sensitivity [MCS]) is considered by some clinicians to be an illness in some people after they are exposed to as yet undefined chemical, biological, or physical agents that are thought to be found in building(s). The term was first used in 1986 and has been controversial ever since. BRI (building-related illness) is becoming the more accepted term used in medical literature.
Sick Building Syndrome Symptoms & Signs
Nosebleeds
Nosebleeds can occur spontaneously when the nasal membranes dry out, crust, and crack, as is common in dry climates, or during the winter months when the air is dry and warm from household heaters. People are more susceptible if they are taking medications that prevent normal blood clotting (Coumadin, warfarin, aspirin, or any anti-inflammatory medication). Other predisposing factors include infection, trauma, allergic and non-allergic rhinitis, hypertension, alcohol abuse, and inherited bleeding problems.
Why is sick building syndrome controversial?
Sick building syndrome is controversial. Although many people and some clinicians believe there is a disease "syndrome" related to buildings and their internal environment, especially the indoor air quality, many other clinicians and medical organizations say there is no convincing clinical evidence that such a medical syndrome exists. The controversy exists because a number of people have a constellation of nonspecific symptoms that have no proven etiology (cause), yet believe they occur from sources inside building(s). Medical organizations such as the American Medical Association (AMA) and many experts say without any defined symptoms and no convincing evidence of a given source or cause, no test to diagnose the syndrome, and no treatment for the syndrome, there is no such medical syndrome.
What types of specialists treat sick building syndrome?
Usually, if there is a problem with a building in which patients are becoming ill, the problems can be first referred to individuals in Occupational Safety and Health Administration (OSHA), the Environmental Protection Agency (EPA), or in some problems like Legionnaires' disease, the Centers for Disease Control and Prevention (CDC). Primary-care physicians and pediatricians usually treat symptoms that are attributed to the air quality in buildings, but other specialists may become involved. For example, allergists, immunologists, specialized building inspectors, and others may be called in to help determine the cause of the problems and ways to solve them.
What causes sick building syndrome?
As stated above, there is controversy about sick building syndrome and the controversy is demonstrated by the medical literature about its cause(s). Those who believe it is a true disease syndrome have only speculated that the cause(s) are multiple and depend on the patient's medical condition (for example, asthma, COPD) and how the compounds in the building (cigarette smoke, chemical outgassing from structural components such as formaldehyde, paint odor, and radon, or biologics such as bacteria and fungi, black mold, or indoor houseplants) interact with the person. Proponents further speculate that patients with the syndrome may be more sensitive to low concentrations of some compounds and may have heightened immune response to such compounds. Further, proponents suggest depression and anxietymay play a role in this syndrome.
Others who say there is no evidence for this syndrome agree that certain chemicals, biologics, and physical agents found in some buildings can cause disease, but once these are identified (for example, lead, Legionnaires' disease, asbestos), then the disease is identified and is not a new "syndrome." The proponents of the "there is no such thing as sick building syndrome" say evidence for a new syndrome is simply nonexistent. A few individuals consider "sick building syndrome" to be a psychological problem.
What are risk factors for sick building syndrome?
Individuals who believe sick building syndrome is real consider the following as some of the major risk factors, but individual people may have only a few of these risk factors:
- Spending time in a building (such as office workers) that causes some or many of the nonspecific symptoms listed below
- Heightened sensitivity to environmental antigens
- Have one or more diagnosed medical problems (for example, asthma)
- Heightened sensitivity of smell
- Females are more likely to develop symptoms
- Gulf War veteran
- Depression
- Anxiety
However, proponents of the opposing view suggest these are general risk factors for many already-defined medical problems and offer little to clinicians who treat patients with the nonspecific symptoms (see symptoms section below) others attribute to this disease.
What are sick building syndrome symptoms and signs?
Proponents of the sick building syndrome agree that people considered to have the syndrome may exhibit any number of nonspecific symptoms that may be increased when the person is associated with certain buildings. The symptoms are as follows:
- Headache
- Nausea
- Diarrhea
- Hoarseness or cough
- Bloating
- Gas
- Dizziness
- Fatigue
- Muscle discomfort (stiffness, pain, cramps, aches)
- Congestion
- Sneezing
- Nosebleeds
- Itching
- Skin rash
- Eye irritation
- Sore throat
- Swelling of legs, trunk, and/or ankles
- Shortness of breath
- Chest pains
- Cardiac arrhythmias
- Mental changes (problems with concentration, memory, moods)
There is no pattern or clear set of symptoms that fit criteria for a new syndrome in the opinion of many clinicians and investigators; these symptoms are often part of symptoms of many other diagnosable medical conditions.
How is sick building syndrome diagnosed?
The vast majority of clinicians, whether they agree or disagree that sick building syndrome exists as a medical entity, agree on one major point; there are no tests that can reliably diagnose the alleged sick building syndrome. However, there are tests for specific causes of illnesses that are related to the local environment. For example, tests for formaldehyde, radon gas, asbestos, lead, and other components such as black mold are available.
What is the treatment for sick building syndrome?
There are no proven treatments for this proposed disease. However, some doctors report reduction of patient's nonspecific symptoms by prescribing antidepressants (for example, fluoxetine [Prozac], paroxetine [Paxil]) or medications for anxiety or medications to help individuals sleep better. In addition, symptomatic treatment, while not treating the unknown cause(s), may provide individual symptom reduction or relief (for example, medication for nausea or headaches).
There may be known conditions in buildings that are related to this proposed syndrome that can be remedied by following building codes and other practices suggested by the EPA and OSHA; some of the major mechanisms are cited in the Prevention section below.
What are complications of sick building syndrome?
The complications of this alleged syndrome include increasing symptoms, interference of job productivity, job loss, necessity of relocation, extensive and expensive building testing (materials and airflow testing), and many medical tests to try to achieve a definitive diagnosis.
What is the prognosis of sick building syndrome?
Because there is no known cause(s), no way to perform a definitive diagnosis, and doubt by many professionals that a sick building syndrome even exists, in general, the prognosis is unclear. However, some people who have had their symptoms treated may have a prognosis that ranges from fair to good.
Is there a way to prevent sick building syndrome?
It is difficult to prevent a syndrome if its cause(s), diagnostic tests, treatments, and its existence is not clear to a large segment of doctors. However, people may be able to prevent some of their nonspecific symptoms by working with their doctors to treat symptoms.
There is still another view of prevention taken by a U.S. government agency, the Environmental Protection Agency. Although the EPA considers sick building syndrome to be a term to serve as an indicator of an unknown illness, it uses the term "building related illness," or BRI, as a term to describe known causes of problems such as toxic gasses and molds, mildew, bacteria, plants, and other known compounds found in buildings (and elsewhere) that can cause complaints, negative health effects, and result in lawsuits. They are related to indoor air quality or indoor air pollution. The EPA cites World Health Organization (WHO) statistics that indicate as many as 30% of all buildings worldwide that are new or refurbished have air-quality problems. In contrast to sick building syndrome, these problems are identifiable and most can be remedied by such methods as using HEPA filters to reduce or eliminate most airborne particles, avoiding building air intakes located near sources of vehicle exhaust fumes or other irritants, and avoiding fungal and bacterial contamination of air conditioning or other air circulating methods. According to the EPA, some people who are termed as having sick building syndrome are actually in a situation where they have a building-related illness that has not been investigated or the source identified. However, that does not make their problem a new syndrome. Appropriate building materials and construction, along with good maintenance techniques can prevent most instance of BRI; some investigators suggest that, in turn, the "sick building syndrome" diagnoses will decrease.
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Medically Reviewed on 9/8/2016
References
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Legionnaires' Disease
Legionnaires' disease and Pontiac fever (legionellosis) facts
- Legionellosis is an infection that is caused by a bacterium.
- The bacterium thrives in droplets of water and moist conditions usually associated with water systems.
- The bacterium can infest an entire building.
- The illness takes two distinct forms: Legionnaires' disease and Pontiac fever.
- Legionnaires' disease is the more severe form and can be fatal.
- Pontiac fever is the far milder form of the illness.
- Symptoms of Legionnaires' disease include fever, chills, and a cough.
- At its worst, Legionnaires' disease can cause severe pneumonia and respiratory failure.
- Although antibiotics are an effective medical treatment, the most useful approach is prevention with the maintenance of water systems.
What causes legionellosis? What is the history of Legionnaires' disease?
Legionellosis is an infection that is caused by a Legionella species called Legionella pneumophila. The disease has two distinct forms:
- Legionnaires' disease is the more severe form of the infection, which may involve pneumonia. The onset of this form of the disease is usually two to 10 days after infection but can occur up to 16 days later. Legionnaires' disease acquired its name in 1976 after an outbreak of pneumonia occurred among people attending the American Legion convention at the Bellevue-Stratford Hotel in Philadelphia. Later, the bacterium causing the illness was named Legionella pneumophila.
- Pontiac fever is a milder illness that develops from hours to two days after initial infection and resolves spontaneously. Sometimes, it may not even cause symptoms.
Antibiotic Treatment of Legionnaires' Disease
Levofloxacin (Levaquin)
Levaquin (brand name) or levofloxacin (generic name) is an antibiotic that is used for treating bacterial infections.
Many common infections in humans are caused by bacteria. Bacteria can grow and multiply, infecting different parts of the body. Drugs that control and eradicate these bacteria are called antibiotics. Levaquin is an antibiotic that stops multiplication of bacteria by preventing the reproduction and repair of their genetic material, DNA. It is in a class of antibiotics called fluoroquinolones.
Where is the Legionella bacterium found?
Legionella organisms can be found in many types of water systems. However, the bacteria reproduce to high numbers in warm, stagnant water (95 F-115 F), such as that which is found in certain plumbing systems and hot-water tanks, cooling towers, and evaporative condensers of large air-conditioning systems, and hot tubs. Cases of legionellosis have been identified throughout the United States and in several other countries. The disease likely occurs worldwide.
The bacterium thrives in the mist aerosolized from air-conditioning ducts. Thus, it can infest an entire building or airplane. Factors that are now known to enhance the growth of Legionella bacteria in human-made water environments include the following:
- Water temperatures of 77 F-107.6 F
- Stagnation of the water
- Scale and sediment in the water
- Certain free-living amoebae organisms in water capable of supporting intracellular growth of Legionellae
What are risk factors for Legionnaires' disease?
People of any age can develop Legionnaires' disease, but the illness most often affects middle-aged and older people, particularly those who smoke cigarettes or have chronic lung disease, as these individuals have a greater likelihood of developing any respiratory illness.
People at an increased risk for Legionnaires' disease also include people whose immune systems are suppressed by diseases and conditions such as cancer, kidney failure requiring dialysis, diabetes, or AIDS. Those who take medications that suppress the immune system are also at risk including those chronically on steroids.
Pontiac fever most commonly occurs in healthy people.
How is Legionnaires' disease spread? How does a person get Legionnaires' disease?
Outbreaks of legionellosis have occurred after people have inhaled aerosols that come from a water source (for example, air-conditioning cooling towers, hot tubs, or showers) contaminated with Legionella bacteria. People may be exposed to these aerosols in homes, workplaces, hospitals, or public places. Person-to-person infection does not occur with legionellosis, and there is no evidence of people becoming infected from vehicle air conditioners or household window air-conditioning units.
Cases of Legionnaires' disease have increased throughout the United States, but this most likely represents increased detection by better diagnostic tests. Some would suggest that this increase may be due to global warming, though this seems unlikely.
Hospital-acquired (nosocomial) infections have occurred and are usually due to contamination of the water supply. Two well-reported cases occurred in the 1980s in Los Angeles, one at the Wadsworth VA hospital and the other at the City of Hope. Guidelines have now been established for routine environmental testing for Legionnaires' in several states in the United States and by the Veterans Affairs health care system.
With regard to travel-associated infection, this usually occurs in hotels from contaminated water, most notably at the Legionnaires' convention in Philadelphia. This disease has also been associated with travel on cruise ships.
Some data suggest an increase incidence of Legionnaires' in the elderly in nursing homes linked to eating puréed food, probably also due to increased aspiration in this population.
How common is Legionnaires' disease?
Legionnaires' pneumonia is not unusual. In fact, it represents over 4% of all community-acquired pneumonias. An additional unknown number of people are infected with the Legionella bacterium but have only mild symptoms or no symptoms at all (so-called Pontiac fever).
Outbreaks of Legionnaires' disease have received the most media attention. A disease outbreak was associated with a party at the Playboy mansion in Los Angeles where at least four individuals contracted Legionnaires' disease. However, the disease most often occurs as single, isolated cases not associated with any identified outbreak. Outbreaks are usually recognized in the summer and early fall, but cases may occur all year long. More recently, outbreaks have been detected in gym participants in Florida and in a police station in New York.
Since the bacterium of Legionnaires' disease was identified in 1976, numerous hospital-acquired outbreaks of the disease have also been reported. These outbreaks have enabled health officials to study epidemics of legionellosis. A recent CDC evaluation reported that one in five Legionnaires' disease cases are linked to health care facilities.
What are the usual symptoms of Legionnaires' disease?
Patients with Legionnaires' disease usually develop a fever, chills, and a cough. The cough may either be dry or produce sputum. Some patients with Legionnaires' disease also have muscle aches, headache, tiredness, loss of appetite, and occasionally diarrhea. Legionnaires' disease can cause a severe pneumonia, seriously affect breathing, even lead to respiratory failure and adult respiratory distress syndrome (ARDS). In some cases, the heart rate is slower than expected for the degree of fever. There are no specific symptoms that directly identify Legionnaires' pneumonia. Legionnaires' pneumonia presents in a manner similar to Chlamydia pneumonia and Mycoplasma pneumonia, so-called atypical pneumonias (previously referred to as "walking pneumonia"). These are referred to as atypical because the associated symptoms and signs are unlike typical pneumonia (as characterized by Streptococcuspneumonia), which involves spiking high fevers, sudden onset, cough, and purulent sputum and often chest pain and a localized infiltrate on chest X-ray.
How is the diagnosis of Legionnaires' disease made?
Laboratory tests may include a modest increase in white blood cells, mild abnormalities in liver function studies, a low sodium in the blood, and even some decreased function of the kidneys. Nevertheless, these features can also be seen with a variety of different types of pneumonia. Chest X-rays often demonstrate abnormal densities (areas of that lungs that on the X-ray film appear whiter). However, it is difficult to distinguish Legionnaires' disease from other types of pneumonia by symptoms and chest X-ray alone. Additional specific tests are required for diagnosis.
These other tests are specialized and are not routinely performed on people with fever or pneumonia. Several types of tests are available. The most useful test uses a urine sample to detect identifiable proteins of the Legionnaires' bacterium (Legionella antigens). This test has the disadvantage of only testing for Legionella pneumophilaserogroup 1 (this is the organism responsible for most of the cases). Additionally, detecting the bacteria in a culture of the sputum may be helpful. Lastly, tests that compare antibody levels of Legionella in two blood samples obtained three to six weeks apart showing a fourfold rise in the antibodies in the blood against the bacterium can be confirmatory after the disease is gone.
Because these tests complement each other, a positive result from each test when Legionnaires' disease is suspected increases the probability of confirming the diagnosis. However, because none of the laboratory tests is 100% sensitive, the diagnosis of legionellosis is not excluded even if one or more of the tests is negative. Of the available tests, the most specific is culture isolation of the bacterium from secretions from the respiratory tract.
What are medical treatments for Legionnaires' disease?
There are three major classes of antibiotics that are effective in treating a Legionellainfection. These include the fluoroquinolones such as levofloxacin (Levaquin), and moxifloxacin (Avelox), the macrolides such as erythromycin, azithromyocin (Zithromax), and clarithromycin (Biaxin), and the tetracyclines including doxycycline(Vibramycin). A new class of antibiotics (glycylcyclines) are also effective. The choice of antibiotic is often dependent on the patient's clinical state, tolerance to the medication, and a health care professional's degree of certainty as to the diagnosis. Zithromax and Levaquin are particularly effective because of decreased gastrointestinal irritation, higher potency, better penetration into tissue, and once-daily dosing.
In severe cases of Legionnaires' disease that seem more resistant to a single antibiotic, a second drug called rifampin (Rifadin) may be added.
Pontiac fever requires no specific treatment.
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