Tb

By direct contact:

• cytomegalovirus

• strep infections (strep throat, scarlet fever, and impetigo)

Fecal-oral route:

• diarrheal disease

By contact with infected blood:

be cleaned after use. Soiled diapers should be disposed of in separate covered waste containers. Staffers should wash hands before and after changing diapers. If a child has diarrhea, staff should don disposable gloves before changing the diaper.

Hands should be washed after using the toilet or handling diapers; after helping a child at the toilet; before preparing, handling, or serving food; before feeding an infant; before setting the table; after wiping or blowing noses; after touching blood, vomit, saliva, or eye secretions; after handling pets; and before and after eating.

chlamydia The most common sexually transmitted disease (STD) in the United States, infecting more than 4.5 million people each year. It is a serious but easily cured disease that is 3 times more common than gon orrhea, 6 times more common than genital herpes, and 30 times more common than syphilis. Between 1988 and 1992, the rate of reported cases of chlamydia more than doubled. Sexually active teens have high rates of chlamydia infections.

The organism that causes chlamydia (chlamydia trachomatis) is classified as a bacterium, even though it is similar to a virus. A parasite that—like a virus—can't reproduce outside living cells, it's enough like bacteria to be vulnerable to antibiotics.

Those at highest risk for contracting the disease are women under age 24, women who take birth control pills, men and women who have had more than one sex partner, and people with other STDs (especially gonorrhea).

In women, the bacteria centers on the cervix, where they cause an inflammation known as mucopurulent cervicitis, which can cause a yellow thick discharge, white blood cells, or bleeding from the cervix that a doctor can diagnosis during a pelvic exam.

Cause A person catches chlamydia during sexual intercourse with a person infected with C. trachomatis, or a baby can contract the disease from an infected mother during birth. (The disease can be transmitted only during birth as the baby passes through the infected birth canal, not during the previous nine months of pregnancy.)

The disease does not confer immunity; some studies suggest that if you have ever had chlamydia, you are more likely to be reinfected sometime in the future.

Symptoms Most women experience no symptoms at all; but even if a woman has no symptoms, she can infect her sex partner. About 20 percent notice a heavy, yellow vaginal discharge. If chlamydia affects the urinary tract, there may be pain, burning, or a frequent urge to urinate.

Many men have symptoms that are so mild they are ignored. The rest experience burning or pain during urination, or notice a watery, milky, or thick discharge from the penis. This is caused by an inflamed urethra.

Some studies suggest that a person can become infected between one to two weeks after exposure. The person remains infectious until the complete course of antibiotics has been taken. Untreated infected people may be infectious for years.

Diagnosis The most reliable test in women is a culture taken from the cervical cells. The current test (90 percent accurate) can identify antibodies in 24 hours. For men, doctors assume that any man with the above symptoms who does not have gonorrhea has chlamydia. Some doctors may try to identify white blood cells in the discharge. A man should be treated for chlamydia if his sex partner has a positive chlamydia test, whether or not he has symptoms.

Tests using urine samples have also recently been developed.

Complications Untreated women may go on to develop infected tubes (salpingitis) or an infected uterus lining (endometritis). PELVIC INFLAMMATORY DISEASE (PID) can lead to a buildup of scar tissue that will block the fallopian tubes, causing infertility or tubal pregnancy. Some studies have linked chlamydia with a higher risk of premature birth or a low-birth-weight baby.

About two-thirds of babies born to infected mothers go on to develop CONJUNCTIVITIS within two weeks of birth, although permanent damage to the baby's eyes is rare. A treated baby is in no risk of permanent damage. About 10 to 20 percent of exposed newborns may develop chlamydia pneumonia in the first three to four months of age. While it is usually mild, some babies may be quite ill and are at risk for developing lung problems later in childhood.

Treatment The disease can be cured by taking antibiotics for seven days (doxycy-cline) or a one-gram single dose of azithromycin. Pregnant women can take ery thromycin for several days. Penicillin is not effective against chlamydia.

Prevention All sexually active young women should be tested for chlamydia; many college health services and family planning clinics routinely test for chlamydia during physical exams. Between 5 to 10 percent of female college students have the disease.

Anyone who is treated for any STD should also be tested for chlamydia. (In some areas of the United States, half of the patients with gonorrhea also have chlamydia.)

The sex partner of anyone with chlamydia must also be treated at the same time; otherwise, reinfection will occur.

Condoms reduce the risk of transmission, but they do not provide complete protection.

All pregnant women should be tested for chlamydia; pregnant women with more than one sex partner or with a partner who has multiple partners should be retested in the third trimester. While many hospitals routinely put erythromycin ointment in the eyes of all newborns to guard against both chlamydia and gonorrhea infections, many babies born to infected mothers still develop chlamydia conjunctivitis chlamydial pneumonia See PNEUMONIA, CHLAMYDIAL.

Chlamydia pneumoniae infection This disease is caused by infection with Chlamydia pneumoniae, one of the varieties of Chlamydia organism that has been linked to respiratory illness and coronary heart disease—specifically, heart attack or atherosclerosis (hardening of the arteries). Because it can be killed by antibiotics, this link to heart disease could be of enormous importance for public health. Up to 10 percent of community-acquired PNEUMONIA may be caused by this bacteria.

Most people are first infected during childhood or early adolescence. Up to 60 percent of all adults around the world have antibodies to

C. pneumoniae, and reinfection may be common. There is suspicion that this organism may also be related to the development of asthma.

Cause Unlike C. psittaci, this organism is spread from person to person by coughing or sneezing. Outbreaks of infection have been reported in families, schools, military barracks, and nursing homes. Often, there is a simultaneous infection with other bacteria or with a virus such as INFLUENZA or RESPIRATORY SYNCYTIAL VIRUS.

Symptoms Between 7 to 21 days after exposure, symptoms of upper respiratory infection appear. Infection is usually mild, but it may be severe, especially among the elderly.

Diagnosis A variety of lab tests can reveal the infection.

Treatment Clarithromycin or azithromycin are the drugs of choice.

Chlamydia psittaci infection Infection with an organism that infects birds and causes a rare type of PNEUMONIA in humans known as psittacosis (ORNITHOSIS). C. psittaci is carried by infected birds, especially parrots.

Cause The infection is acquired through breathing in droplets of bacteria from infected birds and is an occupational hazard for employees of pet shops and poultry processing plants. Birds can be healthy carriers of the organism; increased shedding of bacteria and susceptibility to disease occur during stress, starvation, or egg laying. Person to person transmission is rare, but there have been instances where it has occurred. In the C. psittaci pandemic of 1929-30, infected Argentine birds were shipped to different parts of the world, causing sporadic outbreaks with death rates of up to 40 percent. Since then, the bacterium has been isolated from more than 130 species of birds. All avian species should be considered potentially infectious.

Outbreaks of psittacosis in duck and turkey processing plants show that the infections continue to be a public health concern, despite diagnostic testing, medicated feed, and poultry screening.

Sources of human infection other than infected birds have been identified and may be more common than had previously been thought. C. psittaci has been identified in cats and breeding catteries, for example, which suggests that human infection from pets other than birds may occur.

Symptoms Within 6 to 19 days after exposure to infected birds, the patient experiences a flulike illness with fever, chills, headache and cough, facial pain, rash, joint pain and swelling. In severe cases, there may be an atypical pneumonia.

Diseases associated with exposure to infected animals include spontaneous abortion, symptoms of kidney and liver disease, and heart inflammation. There have also been reports of eye infections and heart problems from people exposed to infected cats and pigeons.

Diagnosis Blood tests can reveal the infection.

Treatment Recommended treatment is tetracycline for three weeks. The death rate is low but many patients experience a lengthy recovery and high incidence of relapse.

Chlamydia trachomatis An organism that lives in the conjunctiva of the eye and the cell layer of the urethra and cervix and is responsible for some types of CONJUNCTIVITIS, nonspecific urethritis, PELVIC INFLAMMATORY DISEASE, and TRACHOMA. It causes one of the most common sexually transmitted diseases in North America (CLAMYDIA) and is a frequent cause of sterility, infecting more than 4.5 million people each year. The World Health Organization estimated 89 million new cases of genital chlamydial infections worldwide in 1995. In the United States, each year an estimated 4 million new cases appear and 50,000 women become infertile as a result of infection.

Chlamydia is a serious but easily cured disease that is 3 times more common than GONORRHEA, 6 times more common than genital HERPES, and 30 times more common than SYPHILIS. Between 1988 and 1992, the rate of reported cases of chlamydia more than doubled. Sexually active teens have high rates of chlamydia infections.

The chlamydia organism is classified as a bacterium, even though it is similar to a virus and was once identified as such by scientists. A parasite that—like a virus—can't reproduce outside living cells, it's enough like bacteria to be vulnerable to antibiotics. It is known as an "energy parasite," since it possesses all the biological features needed for independence except the ability to generate its own energy.

There are three types of the chlamydia organism that are of medical interest; C. trachomatis, C. PSITTACI, and C. PNEUMONIAE. Of these, C. trachomatis is the most important, since it is the cause of the sexually transmitted disease that can cause problems with reproduction. C. trachomatis was first described in China and in the Ebers papyrus in Egypt thousands of years ago; it continues to be a major cause of preventable blindness, with an estimated 500 million cases of active trachoma in the world.

The organism C. trachomatis has two strains; one infects the eyes and/or genitals, and the other causes a swelling and ulceration of the lymph tissue near the groin. This disease, called LYMPHOGRANULOMA VENEREUM has been dropping in the United States except among gay men. It is still common in tropical regions of Africa, Central America, and Asia. The first strain attacks the eyes, causing a disease known as TRACHOMA, now rare in the United States and Europe but one that remains the leading cause of blindness in the Third World.

The second strain has been steadily increasing since the 1960s, causing a range of symptoms from conjunctivitis (inflammation of the rim of the eyes) to infertility. When transmitted sexually, it can cause a range of urinary tract infections in men and women, pelvic inflammatory disease, and ectopic pregnancy. The disease may be passed from an infected mother to a newborn, causing pneumonia. Like other genital organisms, it is often found among young nonwhite, unmarried poor people. More than half of its victims have no symptoms. Antibiotics can kill this pathogen, but condoms are the best protection.

cholera This infection of the small intestine characterized by profuse, painless, watery diarrhea has been one of the great social and political forces in history. If untreated, severe cases can cause rapid dehydration and death within a few hours. If patients are given enough fluids, most will recover. The death rate soars in pandemics when there is not enough clean water, or if so many people become ill that there are not enough healthy people to care for the sick. After one infection, resulting antibodies will protect the patient from reinfection with the same strain.

There has been a dramatic increase in cholera in the United States and its territories, and many cases may go undetected by physicians who are not familiar with the disease, according to the National Center for Infectious Diseases. The disease thrives in places without running water or treated sewage disposal. This is why in the United States and Canada, cholera does not spread from one person to the next; any cholera organisms in infected feces are killed by sewage treatment and chlorinated water. See also TRAVELER'S DIARRHEA; DIARRHEA AND INFECTIOUS DISEASE; ANTIDIARRHEAL DRUGS.

The spread of cholera in the Western world is tied to the problems of 19th-century urbanization, with its lack of sewage control, public water supply, and burgeoning population. While tainted water supplies carry the bacillus, it is also passed in human feces. Therefore, preparing food with unwashed hands, contamination by roaches or flies, and the location of homes and buildings near raw sewage compounds the problem. During the industrialization of the 19th century, families crowded together in dirty tenements and those struggling in coal mining districts were especially at high risk, as were nurses and laundresses who handled soiled linen.

History For centuries cholera thrived only in northeast India, where outbreaks still occur regularly, because of the lack of clean water. In 1784, 20,000 pilgrims died from cholera at an Indian holy place known as Hurdwar. As the world trade routes opened in the 1800s, cholera spread throughout the world, killing millions of people in six distinct pandemics since 1817. The second pandemic reached England in the early 1800s, where London physician John Snow began his investigation of the Broad Street pump, a public source of water drawn from a well near a Soho cesspool. Snow, a general practitioner, was convinced that cholera was found in water and carried by the excretions of victims, and it was Snow who correctly identified sewage-contaminated drinking water as the source of the epidemic. In his research, he compared the incidence of cholera in a neighborhood with two different sources of water, one of which was contaminated with sewage. After he convinced authorities to remove the pump's handle (shutting off the water supply) the neighborhood's outbreak stopped.

In Paris, the pandemic of 1848-49 killed 18,000 people out of a population of 785,000. It was not until the fifth pandemic in 1881 that German and French scientific teams discovered the source of the disease. German microbiologist Robert Koch identified the "comma bacilli" (now called VIBRIO CHOLERAE) under the microscope as the actual cause of cholera.

For the first half of the 20th century, cholera was confined to Asia, and not a single case was reported anywhere in the entire Western Hemisphere between 1911 and 1973. Then between 1974 and 1988, a few cases appeared in U.S. states bordering the Gulf of Mexico (Florida, Louisiana, and Texas). In 1989, no cases were reported.

All cases today are part of a pandemic that began in Indonesia in 1961 with a new strain, called V. cholerae, 01 biotype El Tor. Unexpectedly, in 1991 this cholera epidemic spread to Peru when a ship arrived from the Far East dumped cholera-infected bilge water into the Lima harbor. The bacteria contaminated the fish and shellfish, which Peruvians ate raw; from there the bacteria got into the sewers and from there into the water supply. The disease then spread throughout South and Central America, where the epidemic continues to this day. The particular bacterium can survive in water for long periods. By September 1994, more than a million people in 20 countries had contracted the disease, and more than 9,000 had died.

In most years, there are only a handful of cases in the United States, usually among people who have traveled to Asia or Africa. Cases appear in areas bordering the Gulf of Mexico and around the Mediterranean are usually caused by eating tainted shellfish. From 1961 to 1991, there was an average of five cases per year in the United States; 31 percent of these infections were acquired abroad. From 1992 to 1994, 160 cholera cases were reported in the United States (about 53 per year); this is compared to a total of 136 cases reported in the previous 26 years. Experts suggest the reported cases are probably only a fraction of the actual incidents of cholera, since as many as 90 percent of people with the disease have only mild diarrhea.

Another new strain (V. cholerae 0139) moved across India and Bangladesh into Thailand in 1993, killing thousands of patients on its way. It was carried to California that year by someone who had traveled to India.

Cause Cholera is caused by the comma-shaped bacterium Vibrio cholerae, which is acquired by swallowing food or water conta minated with human feces. A person may also contract cholera from eating fruits or vegetables that are washed in tainted water and eaten raw, by eating raw or undercooked shellfish harvested from contaminated water, or by eating food prepared by someone with contaminated hands. Sometimes, flies can carry the bacteria to food.

The rapid fluid loss that is the primary symptom of cholera occurs because of the action of a toxin produced by the bacterium. This boosts the passage of fluid from the blood into the large and small intestines.

Still, unless there is a huge source of germs (such as contaminated water or the clothes of victims), the disease is fairly hard to acquire. Chlorination can kill the bacteria, and acids in saliva and the stomach are a natural defense.

Symptoms Up to three fourths of all victims show no symptoms. But severe forms of the disease known for hundreds of years as "cholera morbus"—usually among people who have been drinking contaminated water—can be quickly fatal. Between a few hours and five days after infection, symptoms appear suddenly, beginning with incessant diarrhea and vomiting, with severe muscular cramps and prostration. Worse yet, facial features and soft body tissues shrink because of the radical loss of fluid, and discoloration of the skin from ruptured capillaries turns the shriveled victim black and blue. Over a pint of fluid may be lost hourly, and if this is not replaced, death will occur within a few hours. Because the bacteria are inhibited by stomach acid, those with high levels of gastric acid will have only a mild infection. Those who are poorly nourished and have less gastric acid, may have more severe diarrhea.

Many people (especially those living in areas where cholera is common) may have no symptoms, but they can still spread the disease to others. If the diarrhea is very bloody, the cause is probably not cholera but may be Shigella, E. coli, or CAMPYLOBACTER.

Treatment Cholera is treated by quickly replacing the lost fluids with water containing salts and sugar, together with intravenous fluids (if needed). Antibiotics (such as tetracycline) may shorten both the period of diarrhea and the infectiousness. While it is usually taken by mouth, IV tetracycline may be needed for very sick patients. Antidiarrheal medicine should not be taken.

As soon as vomiting stops, the patient should eat a bland diet rich in carbohydrates and low in protein and fats. Airlines are required to carry onboard packets of oral rehydration solution if they carry passengers to and from cholera-infected areas so that anyone developing severe diarrhea on a long flight won't get dehydrated. With proper treatment, most patients will recover with no permanent damage.

Diagnosis A positive stool culture will confirm the diagnosis. Stool specimens must be cultured on special culture media designed to find cholera. A blood test taken a few weeks after the illness begins will show antibodies to cholera.

Complications Patients experience profuse watery diarrhea and without prompt treatment, half the people with severe cholera will die from profound dehydration within a few hours. Symptoms include extreme thirst, lack of urination, cramps, wrinkled skin, sunken eyes, and weakness. Because there will not be enough fluid in the body to maintain circulation, shock, coma, and death can follow.

Prevention A vaccine is available for those traveling to cholera-infested areas but is no longer recommended because it is only 50 percent effective and protects for only three to six months. The vaccine is no help against controlling epidemics. A new, more effective oral vaccine is being tested. The new vaccine is produced in Vietnam, where cholera afflicts more than 3,000 people each year; about 30 of whom will die. Because of its low cost, the new vaccine may be within the limited health care budgets of poor countries.

The bacteria are killed by chlorine or boiling. Contaminated shellfish must be boiled or steamed for 10 minutes to kill all bacteria. The core temperatures of cooked food should be 158 degrees F. Unless all the bacteria are killed by cooking, they will multiply rapidly at room temperature in cooked shellfish.

Cholera can be controlled by improved sanitation, especially by maintaining untainted water supplies. Travelers to high-risk areas (affected areas in Latin America, Africa, and Asia) must follow these guidelines:

• don't bring perishable seafood back to the United States

• don't consume unboiled or untreated water or ice

• don't eat food or beverages from street vendors

• don't eat raw or partially cooked fish or shellfish

• don't eat raw vegetables or salads

• treat unbottled water with chlorine or iodine tablets

• drink carbonated bottled water or bottled soft drinks (the carbonation destroys the bacteria)

• drink tea and coffee made only with boiled water

• eat only fruits that you peel yourself

• eat only foods that are cooked and hot chromomycosis An invasive, chronic fungal infection of the top two layers of the skin on the feet and legs. The infection almost always begins in the skin at the site of trauma, and is most common in the tropics. Called chromomycosis or verrucous dermatitis, the infection may remain localized, or become a generalized infection throughout the body.

Cause This uncommon tropical infection is caused by a group of closely related molds that are found in the soil, affecting people involved in manual labor with soil or its products. While it is not clear why the infection occurs only in the tropics, it is believed that in colder climates, workers wear shoes, which protect feet from contracting chromomycosis. Still, even in the tropics this disorder is not common.

Symptoms The disease begins with an itchy, watery, warty nodule on the leg or foot that develop in a cut or break in the skin. Appearing first as a small dull red lesion, it gradually develops into a large ulcer; over a period of weeks or months, more warty, foul-smelling growths appear in other parts of the skin along the path of lymphatic drainage of the foot, ankle, knee, elbow, or hand. As the ulcer spreads, the central area becomes scarred. Many patients develop secondary bacterial infections.

Treatment Bed rest, elevation of the affected part, and antibiotic therapy to control secondary infections are recommended. Surgical excision of the affected area, destruction of the affected tissue, or drug treatment (potassium iodide, flucytosine, thiabendazole, ketoconazole, and topical heat) may be successful.

Complications This condition is chronic and may last for years or decades, leading to the necessity of amputation, the development of ELEPHANTIASIS, or to squamous cell cancer.

chronic fatigue syndrome A group of symptoms including fatigue, weakness, poor concentration and memory, once derisively dismissed as a new "yuppie flu." Contrary to popular notions, however, the disease is not new; clinical reports of the condition have appeared for more than 100 years. The modern stereotype of "yuppie flu" began because those who sought help in the early 1980s were primarily affluent, well-educated women in their 30s and 40s. Since then, however, physicians have realized the disease strikes those of all ages, races, and social classes in countries around the world, although it is still diagnosed two to four times more often in women than in men.

Quit Smoking For Good

Quit Smoking For Good

Quit smoking for good! Stop your bad habits for good, learn to cope with the addiction of cigarettes and how to curb cravings and begin a new life. You will never again have to leave a meeting and find a place outside to smoke, losing valuable time. This is the key to your freedom from addiction, take the first step!

Get My Free Ebook


Post a comment