national nonprofit organization created to advance research, treatment, prevention, and public awareness of Lyme Disease throughout the United States. Public and professional education are a major focus of the foundation. The group offers a toll-free information number and an established national physician referral system. In addition, members produce educational videos for both the elementary and junior high school levels.
For more information, contact the American Lyme Disease Foundation, Inc., Mill Pond Offices, 293 Route 100, Suite 204, Somers, NY 10589; telephone (914) 277-6970 or (800) 876-LYME; fax (914) 277-6974.
aminoglycosides A family of antibiotics that include gentamicin, amikacin, kanamycin, neomycin, streptomycin, and tobramycin. These drugs may be toxic to the nerve involved in balance or hearing and can damage kidney function.
amoeba (ameba) A microscopic single-celled parasite that is a type of protozoan that takes different shapes as it moves through its watery world. When an amoeba senses food (such as bacteria), it heads in that direction by stretching out a "pseudopod" (false foot) until it is right beside the food. Then the pseudopods stretch out and around the food, trapping it.
Amoeba reproduce by cell division at an extremely fast rate—thousands of generations in one day. However, most of the cells die almost as quickly as they reproduce.
Several species prey on humans, including Entamoeba coli and E. histolytica.
anaerobic bacterial infections A bacterial infection that flourishes in complete or almost complete absence of oxygen, such as clostridium botulinum. These bacteria (called anaerobes) are found throughout nature and in the body. Infections are usually found in deep puncture wounds that are not exposed to air, or in damaged tissue as the result-of trauma, tissue death (necrosis), or an overgrowth of bacteria. Anaerobic organisms can lead to gangrene, tetanus, or botulism.
ancylostomiasis See hookworm disease.
anisakiasis A type of food poisoning caused by the parasitic worm Anasakis simplex (herring worm) or related worms that are found in sushi, the Japanese dish made of raw fish.
Fewer than 10 cases are diagnosed in the United States every year; however, it is suspected that many cases go undiagnosed. Japan has the highest number of cases because of the large amounts of raw fish eaten there.
Cause The parasitic worm Anisakis simplex infests small crustaceans eaten by many kinds of fish, dolphins, and whales. Fertilized eggs from the female parasite are eliminated by the host fish, which develop into larvae that hatch in salt water.
The disease is transmitted by raw, tinder-cooked, or insufficiently frozen fish and shellfish. Its incidence is expected to increase with the increasing popularity of sushi and sashimi bars. In addition to sushi, sashimi, and ceviche, the larvae can be found in raw herring and Pacific salmon and in cod, haddock, fluke, flounder, and monkfish.
Symptoms If the worm is not coughed up or passed into the bowels, it can penetrate the stomach and cause severe pain, nausea, and vomiting and require surgery. Removing the worm or worms is the only known method of reducing the pain and eliminating the infestation.
In North America, the disease is usually diagnosed when the patient begins to feel a tingling or tickling sensation in the throat, and coughs up a worm. In more severe cases, the pain is akin to acute appendicitis, accompanied by nausea.
Symptoms may appear from an hour to two weeks after consuming raw or uncooked seafood.
Diagnosis In cases where the patient coughs up the worm, the diagnosis may be made by examining the worm itself. Otherwise, the physician may need to examine the inside of the stomach and the small intestine.
Prevention The worm is killed by cooking or freezing the fish. Marinating raw fish in lemon or vinegar does not kill all the harmful bacteria or parasites that the fish could contain. Visual inspection of the raw fish, even by the most experienced Japanese chef, will not guarantee the absence of worms.
Anopheles mosquito A genus of mosquito, many species of which transmit the malaria parasites to humans.
anthrax This bacterial infection primarily affects livestock, but it is occasionally spread to humans, causing a skin or lung infection. Bible experts believe the "very severe plague" on the Pharaoh's cattle described in Exodus 9
was almost certainly anthrax. Anthrax is one of the zoonotic diseases, which means that it resides mainly in animals, not in people.
In the 1800s, anthrax was known as "wool-sorter's disease" in England and "ragpicker's disease" in Germany because workers caught it from spores in hides and fibers (respectively). By 1876, bacteriologist Robert Koch developed a way to grow pure anthrax cultures in a lab. Within a year, as anthrax raced through French sheep herds, Louis Pasteur began work on developing a vaccine. He was successful in 1881.
In the 1920s, the United States enacted laws to require testing of horsehair or pig bristle shaving brushes. The largest outbreak ever recorded in this country occurred in 1957, when nine employees of a goat hair processing plant got sick after touching a contaminated shipment from Pakistan; four of the five patients with the pulmonary form of the disease died. Other cases appeared in the 1970s when contaminated goatskin drumheads from Haiti were brought into the country as souvenirs.
Today, anthrax, even among cattle, is rare largely because a vaccine has been developed to protect against the disease. However, some serious epidemics still occur among herds and humans in developing countries because of ineffective control programs. A recent outbreak in Russia occurred when contaminated beef was inadvertently distributed to schools and workers; about 1,500 people were thought to have eaten the diseased meat or had contact with affected animals. Nine people were infected and one died. Infectious diseases, including anthrax, have been on the rise in Russia in the past few years as the state health care system has steadily deteriorated.
There has been some interest in the bacteria as a means of biological warfare; 50 percent of those who inhale between 8,000 and 10,000 spores will die, according to the U.S. Defense Department. Indeed, the largest documented outbreak ever of human inhalation anthrax occurred in Russia in 1979. While officials at the time claimed that the 77 victims got anthrax after eating contaminated meat, in 1992 Russian president Boris Yeltsin said the KGB had admitted a military cause. Two years later, an independent team of American and Russian experts found that a windborne aerosol of anthrax spores from a military lab on April 2, 1979, produced the epidemic that killed 69 of the 77 victims. Why the release occurred has never been explained.
Cause Anthrax is caused by the bacterium bacillus anthracis, which produces spores that can remain dormant for years in soil and animal products such as hides, wool, hair, or bones. B. anthracis can live in pastures for a long time, multiplying rapidly during damp, warm weather. It is especially hardy in the alluvial soil of the Nile valley and the Mississippi River valley (the first North American cases were found among animals in Louisiana in the early 1700s). The disease is often fatal to cattle, sheep, and goats, and their hides, wool, and bones are often heavily contaminated. However, the bacillus is not highly infectious in humans and doesn't depend on multiplication within humans to survive.
If the bacteria are breathed in, they can cause a type of rare and fatal anthrax known as pulmonary anthrax, which attacks the lungs. Intestinal anthrax is a very rare, fatal form of the disease caused by eating the flesh of animals who have died of anthrax. Cutaneous anthrax is the milder form, caused when spores enter the body via a cut.
Symptoms The most common symptom of anthrax is a raised, itchy area at the site of the bacteria's entry, which progresses to a large blister. This is followed by a black scab surrounded by swollen tissue. In fact, the disease gets its name from the Greek word for coal because of this characteristic coal-black sore it causes. Patients also experience shivering and chills, but few other symptoms. In more than 90 percent of cases in humans, the bacteria remain within the sore.
Occasionally, the bacteria may spread to the nearest lymph node, or in rare cases it may escape into the bloodstream, causing rapidly fatal blood poisoning, internal bleeding, or anthrax meningitis.
Intestinal anthrax causes stomach and intestinal inflammation and ulcers, much like the sores that appear on the skin in cutaneous anthrax.
Pulmonary anthrax patients experience a suffocating bronchitis that is usually fatal.
Treatment Anthrax is curable in the early stages with high doses of penicillin, but it can be fatal in advanced stages. A vaccine is available to protect against the disease.
Prognosis One or 2 out of 10 patients will die from anthrax of the skin if it is not properly treated. A full 100 percent of patients will die of inhalation anthrax if untreated.
antibacterial drugs A group of drugs used to treat infections caused by bacteria. These drugs share the same actions of antibiotic drugs but (unlike the antibiotics) have always been produced synthetically. The largest group of antibacterial agents are the sulfonamides. Medically, physicians do not differentiate antibacterials from antibiotics.
antibiotic drugs A group of drugs used to treat infections caused by bacteria. Originally prepared from molds and fungi, antibiotic drugs are today produced synthetically. Antibiotics fight infection when the body has been invaded by harmful bacteria, or when the bacteria in the body begin to multiply uncontrollably.
Some drugs, known as broad-spectrum antibiotics, are effective against a wide range of bacteria, whereas others are useful only in treating a specific bacterium. Some of the best-known antibiotics include the macrolides (erythromycin and clarithromycin); the penicillins (amoxicillin, penicillin V, and oxacillin); the aminoglycosides (gentamicin and streptomycin); the cephalosporins (cefaclor and cephalexin); the quinolones (ciprofloxacin and ofloxacin); and the tetracyclines (doxycycline and oxytetracycline).
Still, these drugs can cause some side effects. Antibiotics kill bacteria, but they can also reduce the "good" bacteria naturally present in the body. When this happens, different bacteria or fungi can grow in their place, causing oral, intestinal, or vaginal candidiasis (thrush).
Some patients are allergic to antibiotics and can develop swelling, itching, or breathing problems if they take these drugs. A severe allergic reaction to antibiotics (especially penicillin) can be fatal.
When penicillin was first introduced in the 1940s, doctors finally had a good way to treat infections that had previously claimed thousands of lives. Penicillin and its cousin, ampi-cillin, were called "wonder drugs" and were soon among the most widely prescribed drugs in the world. Unfortunately, even the best of these drugs can't kill every single bacterium. When an antibiotic was used against a bacterial infection, it destroyed only those bacteria that were susceptible to the drug; resistant strains were left behind, to survive and spread. Over time, this occurred often enough so that today there are many bacteria resistant to the most-prescribed antibiotics. Resistance occurs when a bacterium is able to evolve so that it is no longer harmed by the specific antibiotic.
The problem is worse in other parts of the world (Europe, the Far East, and South America), where antibiotics are widely available without a prescription. This has led even more quickly to drug-resistant strains in other parts of the world, which are now circulating the globe. See also antibacterial drugs.
Resistance Resistance is likely to develop if a person doesn't take antibiotics long enough; this leaves a few super-strong germs behind. Drugs kill the vulnerable strains of germs, but the tough survive and flourish. Indeed, half of all antibiotics prescribed in the
United States today are either misused or unneeded, according to medical experts.
Resistance also occurs when doctors over-prescribe antibiotics instead of saving them for specific infections that really require such a drug. Too often, doctors prescribe antibiotics for viral infections (which antibiotics cannot treat). Some doctors defend this practice by saying the cost of a culture to identify the source of the infection is more expensive than the antibiotic. Patients also pressure physicians to prescribe antibiotics. For this reason, the U.S. Centers for Disease Control and Prevention (CDC) has issued guidelines urging hospitals and doctors to use antibiotics more sparingly to slow the development of drug-resistant strains of germs.
Among bacteria that have concerned public health officials are certain types of "flesh eating" strep, and bacteria that cause ear infection, tuberculosis, pneumonia, meningitis, and sepsis (an often-fatal blood infection). Some hospitals cannot treat enterococci that can infect kidneys, bladders, wounds, and blood because they have become resistant even to vancomycin, the drug of last resort. (See vancomycin-resistant enterococci.) According to one CDC study, about 13,300 Americans died in 1992 alone from infections that were no longer sensitive to antibiotics. Every year, another 60,000 to 70,000 patients die from hospital-acquired infections, half of which are caused by drug resistant super-bugs. Scientists believe that antibiotic resistance is a major threat to the nation's health, since many diseases are no longer treatable by antibiotics that were effective against them even a few years ago.
Scientists are racing against time to develop new types of drugs that will be effective against some of the most deadly infections. Because scientists had mistakenly thought the world had enough antibiotics, drug companies began moving away from antibiotic research in the 1980s. Drug development is also expensive: It costs about $237
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The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.