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Medical Microbiology. Epidemic typhus Rickettsia prowazekii causes epidemic typhus. It is spread by lice. Brill-Zinsser disease is a mild form of epidemic.

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Presentation on theme: "Medical Microbiology. Epidemic typhus Rickettsia prowazekii causes epidemic typhus. It is spread by lice. Brill-Zinsser disease is a mild form of epidemic."— Presentation transcript:

1 Medical Microbiology

2 Epidemic typhus Rickettsia prowazekii causes epidemic typhus. It is spread by lice. Brill-Zinsser disease is a mild form of epidemic typhus. It occurs when the bacteria re-activates in a person who was previously infected. It is more common in the elderly.

3 Symptoms of epidemic typhus may include: Chills Confusion Cough Delirium High fever (104 degrees Fahrenheit) Joint pain (arthralgia) Lights that appear very bright; light may hurt the eyes Low blood pressure Rash that begins on the chest and spreads to the rest of the body (except the palms of the hands and soles of the feet) Severe headache Severe muscle pain (myalgia) Stupor The early rash is a light rose color and fades when you press on it. Later, the rash becomes dull and red and does not fade. People with severe typhus may also develop small areas of bleeding into the skin (petechiae). Epidemic typhus

4 murine or endemic typhus Rickettsia typhi causes murine or endemic typhus. Endemic typhus is uncommon in the United States. It is usually seen in areas where hygiene is poor and the temperature is cold. Endemic typhus is sometimes called "jail fever." The bacteria that causes this type is usually spread by rats to fleas to humans. Murine typhus occurs in the southern United States, particularly California and Texas. It is often seen during the summer and fall. It is rarely deadly. You are more likely to get this type of typhus if you are around rats feces or fleas, and other animals such as cats, opossums, raccoons, and skunks.

5 Symptoms of murine or endemic typhus may include: Abdominal pain Backache Dull red rash that begins on the middle of the body and spreads Extremely high fever ( degrees Fahrenheit), which may last up to 2 weeks Hacking, dry cough Headache Joint and muscle pain Nausea Vomiting murine or endemic typhus

6 Treatment of typhus Treatment includes antibiotics such as: Doxycycline Tetracycline Chloramphenicol (less common) Tetracycline taken by mouth can permanently stain teeth that are still forming. It is usually not prescribed for children until after all of their permanent teeth have grown in. Patients with epidemic typhus may need intravenous fluids and oxygen.

7 Rocky Mountain spotted fever Rocky Mountain spotted fever is caused by Rickettsia rickettsii (R. Rickettsii), which is carried by ticks. The bacteria spread to humans through a tick bite. In the western United States, the bacteria are carried by the wood tick, and in the eastern U.S. they are carried by the dog tick. Other ticks spread the infection in the southern U.S. and in Central and South America.

8 Contrary to the name "Rocky Mountain," most recent cases have been reported in the eastern United States, including North and South Carolina, Virginia, Maryland, Georgia, Tennessee, and Oklahoma. Most cases occur in the spring and summer. About 2,300 cases were reported in Most of the reported cases have been in children. Rocky Mountain spotted fever

9 Risk factors include recent hiking or exposure to ticks in an area where the disease is known to occur. The bacteria are unlikely to be transmitted to a person by a tick that has been attached for less than 20 hours. Only about 1 in 1,000 wood and dog ticks carry the bacteria. Bacteria can also infect people who crush ticks they have removed from pets with their bare fingers. Rocky Mountain spotted fever

10 Symptoms usually develop about 2 to 14 days after the tick bite. They may include: Chills Confusion Fever Headache Muscle pain Rash -- usually starts a few days after the fever; first appears on wrists and ankles as spots that are mm in diameter, then spreads to most of the body. About one-third of infected people do not get a rash. Rocky Mountain spotted fever

11 Treatment involves careful removal of the tick from the skin and antibiotics to get rid of the infection. Doxycycline or tetracycline are the drugs of choice for both confirmed and suspected cases. Pregnant women may take chloramphenicol. Note: There is concern that tetracycline and doxycycline may stain the teeth of children whose permanent teeth have not yet formed. However, tooth discoloration is very unusual when a child takes these medicines for 14 days or less. These medicines are first-line treatment, even for children.

12 Rocky Mountain spotted fever Treatment usually cures the infection. Complications are rare, but can include paralysis, hearing loss, and nerve damage. About 3% of people who get this disease will die.

13 Typhus

14 Rocky Mountain Spotted Fever

15 Ehrlichiosis Ehrlichiosis is caused by bacteria that belong to the family called Rickettsiae. Scientists first described ehrlichiosis in There are two types of the disease in the United States: Human monocytic ehrlichiosis (HME) is caused by the rickettsial bacteria Ehrlichia chaffeensis. Human granulocytic ehrlichiosis (HGE) is also called human granulocytic anaplasmosis (HGA). It is caused by the rickettsial bacteria called Anaplasma phagocytophilum.

16 Ehrlichia bacteria can be carried by the: American dog tick Deer tick -- which can also cause Lyme disease Lone Star tick In the United States, HME is found mainly in the southern central states and the Southeast. HGE is found mainly in the Northeast and upper Midwest. Risk factors for ehrlichiosis include: Living near an area with a lot of ticks Owning a pet that may bring a tick home Walking or playing in high grasses

17 Ehrlichiosis The time between the tick bite and when symptoms occur is about days. This is called the incubation period. Symptoms may seem like the flu (influenza), and may include: Chills Fever Headache Muscle aches Nausea

18 Ehrlichiosis A rash appears in fewer than half of cases. Sometimes, the disease may be mistaken for Rocky Mountain spotted fever. The symptoms are often general, but patients are sometimes sick enough to see a doctor.

19 Ehrlichiosis Antibiotics (tetracycline or doxycycline) are used to treat the disease. Children should not take tetracycline by mouth until after all their permanent teeth have grown in, because it can permanently change the color of growing teeth. Doxycycline that is used for 2 weeks or less usually does not discolor a child's permanent teeth.

20 Ehrlichiosis Ehrlichiosis is rarely deadly. With antibiotics, patients usually improve within hours. Recovery takes 3 weeks.

21 Crown Gall Crown Gall is a common disease of many woody shrubs and some herbaceous plants. It is caused by the bacterium Agrobacterium tumefaciens which can infect 140 genera in over 90 families of plants. It is especially common in the rose family. The Agrobacteria have been extensively studied over the last 80 years. They are useful today in the genetic engineering of plants because of their ability to integrate parts of their own DNA into a plants genome. In nature this ability allows the transformation of normal plant cells into tumor cells.


23 Cat scratch disease CSD; Cat scratch fever; Bartonellosis Cat scratch disease is an infection with Bartonella bacteria that is believed to be transmitted by cat scratches and bites.

24 Cat scratch disease Cat scratch disease is caused by Bartonella henselae. The disease is spread through contact with an infected cat (a bite or scratch), or contact with cat saliva on broken skin or the white of the eye.

25 A person who has had contact with an infected cat may show common symptoms, including: Bump (papule) or blister (pustule) at site of injury (usually the first sign) Fatigue Fever (in some patients) Headache Lymph node swelling (lymphadenopathy) near the site of the scratch or bite Overall discomfort (malaise)

26 Generally, cat scratch disease is not serious. Medical treatment is not usually needed. In severe cases, treatment with antibiotics such as azithromycin can be helpful. Other antibiotics may be used including clarithromycin, rifampin, trimethoprim-sulfamethoxazole, or ciprofloxacin. In AIDS patients and other people who have a weakened immune system, cat scratch disease is more serious, and treatment with antibiotics is recommended.

27 Brucellosis Rock fever; Cyprus fever; Undulant fever; Gibraltar fever; Malta fever; Mediterranean fever Brucellosis is an infectious disease that occurs from contact with animals carrying Brucella bacteria.

28 Brucella can infect cattle, goats, camels, dogs, and pigs. The bacteria can spread to humans if you come in contact with infected meat or the placenta of infected animals, or if you eat or drink unpasteurized milk or cheese. Brucellosis is rare in the United States. About cases occur each year. People working in jobs where they often come in contact with animals or meat -- such as slaughterhouse workers, farmers, and veterinarians -- are at higher risk.

29 Acute brucellosis may begin with mild flu-like symptoms, or symptoms such as: Abdominal pain Back pain Chills Excessive sweating Fatigue Fever Headache Joint pain Loss of appetite Weakness Weight loss

30 High fever spikes usually occur every afternoon. The name "undulant" fever is because the fever rises and falls in waves. Antibiotics are used to treat the infection and prevent it from coming back. Longer courses of therapy may be needed if there are complications. Relapse may occur, and symptoms may continue for years. As with tuberculosis, the illness can come back after a long period of time.

31 Melioidosis an infectious disease caused by a Gram-negative bacterium, Burkholderia pseudomallei, found in soil and water. It is of public health importance in endemic areas, particularly in Thailand and northern Australia. It exists in acute and chronic forms. Symptoms may include pain in chest, bones, or joints; cough; skin infections, lung nodules and pneumonia.

32 The single most important risk factor for developing severe melioidosis is diabetes mellitus. Other risk factors include thalassaemia, kidney disease, occupation (rice paddy farmers), and cystic fibrosis. The mode of infection is believed to be either through a break in the skin, or through the inhalation of aerosolized B. pseudomallei. Person-to-person spread has been described but is extremely unusual.

33 Burkholderia cepacia complex (BCC), or simply Burkholderia cepacia B. cepacia is an important human pathogen which most often causes pneumonia in immunocompromised individuals with underlying lung disease (such as cystic fibrosis or chronic granulomatous disease).

34 Infection control The bacterium is so hardy, it has been found to persist in betadine (a common topical antiseptic). Recently, a 0.2% chlorhexidine mouthwash was also recalled, after it was found to be contaminated with B. cepacia. On 1-August-2012, the US FDA announced a recall of selected lots of benzalkonium chloride swabs and antiseptic wipes manufactured for Dukal by Jianerkang Medical Dressing Co.

35 Treatment typically includes multiple antibiotics and may include ceftazidime, doxycycline, piperacillin, meropenem, chloramphenicol and trimethoprim/sulfamethoxazole(co-trimoxazole). Although co-trimoxazole has been generally considered the drug of choice for B. cepacia infections, ceftazidime, doxycycline, piperacillin and meropenem are considered to be viable alternative options in cases where co-trimoxazole cannot be administered because of hypersensitivity reactions, intolerance or resistance. In April 2007, researchers from the Schulich School of Medicine and Dentistry at the University of Western Ontario, working with a group from Edinburgh, announced they had discovered a way to kill the organism.

36 Pertussis Whooping cough Pertussis is a highly contagious bacterial disease that causes uncontrollable, violent coughing. The coughing can make it hard to breathe. A deep "whooping" sound is often heard when the patient tries to take a breath.

37 Pertussis, or whooping cough, is an upper respiratory infection caused by the Bordetella pertussis or Bordetella parapertussis bacteria. It is a serious disease that can cause permanent disability in infants, and even death. When an infected person sneezes or coughs, tiny droplets containing the bacteria move through the air, and the disease is easily spread from person to person. The infection usually lasts 6 weeks. Whooping cough can affect people of any age. Before vaccines were widely available, the disease was most common in infants and young children. Now that most children are immunized before entering school, the higher percentage of cases is seen among adolescents and adults.

38 Initial symptoms, similar to the common cold, usually develop about a week after exposure to the bacteria. Severe episodes of coughing start about 10 to 12 days later. In children, the coughing often ends with a "whoop" noise. The sound is produced when the patient tries to take a breath. The whoop noise is rare in patients under 6 months of age and in adults. Coughing spells may lead to vomiting or a short loss of consciousness. Pertussis should always be considered when vomiting occurs with coughing. In infants, choking spells are common. Other pertussis symptoms include: Runny nose Slight fever (102 °F or lower) Diarrhea

39 If started early enough, antibiotics such as erythromycin can make the symptoms go away more quickly. Unfortunately, most patients are diagnosed too late, when antibiotics aren't very effective. However, the medicines can help reduce the patient's ability to spread the disease to others. Infants younger than 18 months need constant supervision because their breathing may temporarily stop during coughing spells. Infants with severe cases should be hospitalized. An oxygen tent with high humidity may be used. Fluids may be given through a vein if coughing spells are severe enough to prevent the person from drinking enough fluids. Sedatives (medicines to make you sleepy) may be prescribed for young children. Cough mixtures, expectorants, and suppressants are usually not helpful and should NOT be used.

40 In older children, the outlook is generally very good. Infants have the highest risk of death, and need careful monitoring.

41 Gonorrhea Clap; The drip Gonorrhea is a common sexually transmitted infection (STI).

42 Gonorrhea is caused by the bacteria Neisseria gonorrhoeae. Anyone who has any type of sex can catch gonorrhea. The infection can be spread by contact with the mouth, vagina, penis, or anus. The bacteria grow in warm, moist areas of the body, including the tube that carries urine out of the body (urethra). In women, the bacteria may be found in the reproductive tract (which includes the fallopian tubes, uterus, and cervix). The bacteria can even grow in the eyes.

43 Health care providers in every state in the U.S. are required by law to tell their State Board of Health about anyone diagnosed with gonorrhea. The goal of this law is make sure the patient gets proper follow-up care and that their sexual partners are found and tested.

44 You are more likely to develop this infection if you: Have multiple sexual partners Have a partner with a past history of any sexually transmitted infection Do not use a condom during sex Abuse alcohol or illegal substances

45 Symptoms of gonorrhea usually appear days after infection, however, in men, symptoms may take up to a month to appear. Some people do not have symptoms. They may be completely unaware that they have caught the infection, and therefore do not seek treatment. This increases the risk of complications and the chances of passing the infection on to another person.

46 Symptoms in men include: Burning and pain while urinating Increased urinary frequency or urgency Discharge from the penis (white, yellow, or green in color) Red or swollen opening of penis (urethra) Tender or swollen testicles Sore throat (gonococcal pharyngitis)

47 Symptoms in women can be very mild or nonspecific, and may be mistaken for another type of infection. They include: Vaginal discharge Burning and pain while urinating Increased urination Sore throat Painful sexual intercourse Severe pain in lower abdomen (if the infection spreads to the fallopian tubes and stomach area) Fever (if the infection spreads to the fallopian tubes and stomach area) If the infection spreads to the bloodstream, fever, rash, and arthritis-like symptoms may occur.

48 There are two goals in treating a sexually transmitted disease, especially one as easily spread as gonorrhea. The first is to cure the infection in the patient. The second is to locate and test all of the other people the person had sexual contact with and treat them to prevent further spread of the disease. Never treat yourself without being seen by your doctor first. Your health care provider will determine the best and most up-to-date treatment.

49 About half of the women with gonorrhea are also infected with chlamydia, another very common sexually transmitted infection. Chlamydia is treated at the same time as a gonorrhea infection. You should receive the hepatitis B vaccine. If you are younger than 26, you also need the HPV vaccine. A follow-up visit 7 days after treatment is important if joint pain, skin rash, or more severe pelvic or belly pain is present. Tests will be done to make sure the infection is gone.

50 All sexual contacts of the person with gonorrhea should be contacted and tested. This helps prevent further spread of the disease. In some places you may be able to take counseling information and medicines to your sexual partner yourself. In other places, the health department will contact your partner.

51 Meningitis - meningococcal Meningococcal meningitis is an infection that results in swelling and irritation (inflammation) of the membranes covering the brain and spinal cord.

52 Meningococcal meningitis is caused by the bacteria Neisseria meningitidis (also known as meningococcus). Most cases of meningococcal meningitis occur in children and teens. Meningococcus is the most common cause of bacterial meningitis in children and a leading cause of bacterial meningitis in adults. The infection occurs more often in winter or spring. It may cause local epidemics at boarding schools, college dormitories, or military bases. Risk factors include recent exposure to meningococcal meningitis and a recent upper respiratory infection.

53 Symptoms usually come on quickly, and may include: Fever and chills Mental status changes Nausea and vomiting Purple, bruise-like areas (purpura) Rash, pinpoint red spots (petechiae) Sensitivity to light (photophobia) Severe headache Stiff neck (meningismus)

54 Antibiotics should be started as soon as possible. Ceftriaxone is one of the most commonly used antibiotics for meningococcal meningitis. Penicillin in high doses is almost always effective, too. If the patient is allergic to penicillin, chloramphenicol may be used. Sometimes corticosteroids may be used, especially in children. People in close contact with someone who has meningococcal meningitis should be given antibiotics to prevent infection. Such people include: Household members Roommates in dormitories Those who come into close and long-term contact with an infected person

55 Early treatment improves the outcome. Death is possible. Young children and adults over 50 have the highest risk of death. Vaccines are effective for controlling epidemics. They are currently recommended for: Adolescents College students in their first year living in dormitories Military recruits Travelers to certain parts of the world

56 Tularemia Deerfly fever; Rabbit fever; Pahvant Valley plague; Ohara disease; Yato-byo (Japan); Lemming fever Tularemia is an infection common in wild rodents that is passed to humans through contact with infected animal tissues or by ticks, biting flies, and mosquitoes.

57 Tularemia is caused by the bacterium Francisella tularensis. Humans can get the disease through: A bite from an infected tick, horsefly, or mosquito Breathing in infected dirt or plant material Direct contact, through a break in the skin, with an infected animal or its dead body (most often a rabbit, muskrat, beaver, or squirrel) Eating infected meat (rare)

58 The disorder most commonly occurs in North America and parts of Europe and Asia. Although outbreaks can occur in the United States, they are rare. Some people may develop pneumonia after breathing in infected dirt or plant material. This is known to occur on Martha's Vineyard, where bacteria are present in rabbits, raccoons, and skunks. Francisella tularensis is considered a potential bioterrorism agent. An aerosol release would be a possible method of infection. Pneumonia cases would start days after people were exposed.

59 The incubation period is 3 to 5 days after exposure. The illness usually starts suddenly, and may continue for several weeks after symptoms begin. Chills Eye irritation ( conjunctivitis -- if the infection began in the eye) Fever Headache Joint stiffness Muscle pains Red spot on the skin, growing to become a sore (ulcer) Shortness of breath Sweating Weight loss

60 The goal of treatment is to cure the infection with antibiotics. Streptomycin and tetracycline are commonly used to treat this infection. Once daily gentamicin treatment has been tried with excellent results as an alternative therapy to streptomycin. However, because this is a rare disease, only a few cases have been studied to-date. Tetracycline and chloramphenicol can be used alone, but they have a high relapse rate and are not considered a first-line treatment. Note: Oral tetracycline is usually not prescribed for children until after all their permanent teeth have come in. It can permanently discolor teeth that are still forming.

61 Tularemia is fatal in about 5% of untreated cases, and in less than 1% of treated cases.

62 Pseudomonas Infections Pseudomonas is a clinically significant and opportunistic pathogen, often causing nosocomial infections. In addition to causing serious and often life-threatening diseases, these organisms exhibit innate resistance to many antibiotics and can develop new resistance after exposure to antimicrobial agents. Some pseudomonal species that previously were considered the causative agents of old diseases now are being reexamined for their potential use as biological warfare agents.

63 The current classification of the genus Pseudomonas is divided into 5 groups based on ribosomal RNA (rRNA)/DNA homology. Of the more than 20 pseudomonal species that have been found from human clinical specimens, the following 4 representative organisms are discussed in this article: P aeruginosa (homology group I) Pseudomonas cepacia (group II) Pseudomonas pseudomallei (group II) Pseudomonas mallei (group II)

64 Although P aeruginosa is a common human saprophyte, it rarely causes disease in healthy persons. Most infections with this organism occur in compromised hosts. Examples of compromising conditions include disrupted physical barriers to bacterial invasion (eg, burn injuries, intravenous [IV] lines, urinary catheters, dialysis catheters, endotracheal tubes) and dysfunctional immune mechanisms, such as those that occur in neonates and in individuals with cystic fibrosis (CF), acquired immunodeficiency syndrome (AIDS), neutropenia, complement deficiency, hypogammaglobulinemia, and iatrogenic immunosuppression.

65 In healthy children, disease is primarily limited to the first 2 stages (as in diseases such as otitis externa, urinary tract infections (UTIs), dermatitis, cellulitis, and osteomyelitis), although recent case reports describe bacteremia, sepsis, and GI infections in previously healthy children. In immunocompromised hosts, including neonates, infection can progress rapidly through the 3 stages and cause pneumonia, endocarditis, peritonitis, meningitis, ecthyma gangrenosum (EG), bacteremia, and overwhelming septicemia.

66 Pseudomonas cepacia In 1949, Walter Burkholder of Cornell University first described P cepacia (now known as Burkholderia cepacia) as the phytopathogen responsible for the bacterial rot of onions.[3] In the 1950s, B cepacia was first reported as a human pathogen that causes endocarditis. Subsequently, the organism has been found in numerous catheter-associated UTIs, wound infections, and IV catheter–associated bacteremias.

67 n 1971, this species was reported as the causative organism of foot rot in US troops on swamp training exercises in northern Florida; it also was isolated from troops serving in Vietnam's Mekong Delta. In 1972, B cepacia was discovered as an opportunistic human pathogen in a patient with CF. Since then, B cepacia has emerged with increasing frequency as the cause of pneumonia and septicemia in children with CF.

68 Pseudomonas mallei P mallei (now known as Burkholderia mallei) causes glanders, a serious infectious disease of animals (primarily horses, although it has also been isolated in donkeys, mules, goats, dogs, and cats). Transmission is believed to occur through direct contact. Glanders transmission to humans is rare and presumably occurs through inoculation of broken skin or the nasal mucosa with contaminated discharges. Manifestation of the disease in humans varies, ranging from an acute localized suppurative infection, acute pulmonary infection, or acute septicemic infection to chronic suppurative infection. Fulminant disease with multiple organ system involvement occurs with septicemic infection.

69 Pseudomonas pseudomallei P pseudomallei (now known as Burkholderia pseudomallei) causes melioidosis (from the Greek, "resemblance to distemper of asses"). Melioidosis, also called Whitmore disease, clinically and pathologically resembles glanders but has an entirely different epidemiologic profile from B mallei. It occurs in many animals (eg, sheep, goats, horses, swine, cattle, dogs, cats). Transmission is believed to occur through direct contact, although inhalation reportedly is a possible route of acquisition. Since the first description of the disease from North Queensland, Australia, in 1962, melioidosis has spread to Southeast Asia.

70 B pseudomallei is found in contaminated water and soil. The pathogen spreads to humans and animals through direct contact with a contaminated source. In otherwise healthy hosts, disease manifestations range from acute to chronic local suppurative infections to septicemia with multiple abscesses in all organs of the body.

71 According to data from the Centers for Disease Control and Prevention (CDC) National Nosocomial Infections Surveillance System, P aeruginosa can be rated as follows: Number 1 cause of intensive care unit (ICU)– related pneumonia Number 1 cause of osteochondritis Number 2-ranked gram-negative organism, responsible for 9% of all nosocomial bacterial and fungal isolates

72 Number 2 cause of nosocomial pneumonia Number 3-ranked isolate in hospital-acquired UTIs Number 4 cause of surgical site infections and of hospital-acquired gram-negative rod bacteremia Number 5 hospital pathogen Number 8-ranked bloodstream isolate Causes 10% of nosocomial infections

73 Most common gram-negative organism isolated from corneal ulcers and endocarditis Frequent cause of contact lens–associated keratitis Second most frequent cause of brain abscess and meningitis in patients with cancer Third most common cause of recurrent UTIs complicated by obstruction, catheters, or stones Fifth most common cause of recurrent UTIs in schoolchildren

74 Pseudomonas aeruginosa is so ubiquitous in the hospital environment that distinguishing infection from colonization is often difficult. Furthermore, symptoms are often identical to those observed in other gram-negative infections. As a result, clinical evidence of infection should accompany any culture of the organism at a potential infection site. P aeruginosa reportedly emits a characteristic sweet odor. P aeruginosa is responsible for a broad spectrum of disease, including the following types of infections:

75 AIDS-related infections Bacteremia and sepsis Fever is often the initial symptom. Some patients may also present with tachypnea or tachycardia. Hypotension and shock may develop. Jaundice may occur. Suspect pseudomonal bacteremia in individuals who are immunocompromised (including neonates), who have an extended hospitalization, who have received prolonged antibiotic administration or multiple antibiotics, or who have indwelling catheters.

76 Febrile neutropenia Bone and joint infection (eg, osteochondritis, osteomyelitis, pyarthrosis) Skin and soft tissue infections (eg, burn wound sepsis, dermatitis, ecthyma gangrenosum [EG], pyoderma, cellulitis, hot tub folliculitis, necrotizing fasciitis, chronic paronychia) CNS infection (eg, brain abscess, meningitis) Ear infections (eg, otitis media, chronic suppurative otitis media, otitis externa, malignant external otitis) Eye infections (eg, endophthalmitis, keratitis, ophthalmia neonatorum, blepharoconjunctivitis, scleral abscess, orbital cellulitis)

77 GI infections (eg, epidemic diarrhea, necrotizing enterocolitis (NEC), typhlitis, rectal abscess, Shanghai fever) GU infections (eg, epididymitis, prostatitis, urethritis, UTIs): The clinical presentation of pseudomonal UTIs is indistinguishable from other bacterial UTIs. Cardiovascular (CV) infections (eg, endocarditis, pericarditis, cardiac tamponade) Respiratory infections (eg, primary or nonbacteremic, bacteremic, colonization, and nosocomial pneumonia, lower respiratory tract infections of cystic fibrosis [CF], ventilator- associated pneumonia [VAP])

78 Erythematous papulopustules of pseudomonas folliculitis. Courtesy of Mark Welch, MD.

79 Antimicrobial agents are needed to treat Pseudomonas infections. Two antipseudomonal drug combination therapy (eg, a beta-lactam antibiotic with an aminoglycoside) is usually recommended for the initial empiric treatment of a pseudomonal infection, especially for patients with neutropenia, bacteremia, sepsis, severe upper respiratory infections (URIs), or abscess formation. The choice of antibiotic also depends on the site and extent of infection and on local resistance patterns. Reports of more resistant strains of Pseudomonas organisms to the currently used antimicrobials are causing much concern.

80 Blepharoconjunctivitis Blepharoconjunctivitis may be acute [blepharoconjunctivitis - acute] or chronic [blepharoconjunctivitis - chronic] and may be caused by bacteria (Moraxella lacunata, Staphylococcus aureus) or viruses (Herpes simplex). An allergic blepharoconjunctivitis may also result from a contact allergy, as after neomycin eyedrops. The most common cause of chronic bacterial blepharoconjunctivitis is Staphylococcus aureus, which lives in the eyelid margin and not only directly infects the conjunctiva, but also causes conjunctivitis by the elaboration of powerful exotoxins. Angular blepharoconjunctivitis [blepharoconjunctivitis - angular] is most frequently due to Moraxella lacunata and marginal corneal ulcers are often associated. These ulcers are typically gray and separated from the corneoscleral limbus by a clear cresecent. Chronic angular blepharoconjunctivitis may be accompanied by chronic follicular conjunctivitis [conjunctivitis - follicular]. Blepharoconjunctivitis due to Moraxella tends to affect the skin adjacent to the medial and lateral canthi (angular blepharitis).


82 Acinetobacter in Healthcare Settings Acinetobacter is a group of bacteria commonly found in soil and water. While there are many types or species of Acinetobacter and all can cause human disease, Acinetobacter baumannii accounts for about 80% of reported infections. Outbreaks of Acinetobacter infections typically occur in intensive care units and healthcare settings housing very ill patients. Acinetobacter infections rarely occur outside of healthcare settings.

83 Acinetobacter causes a variety of diseases, ranging from pneumonia to serious blood or wound infections, and the symptoms vary depending on the disease. Acinetobacter may also colonize or live in a patient without causing infection or symptoms, especially in tracheostomy sites or open wounds.

84 Legionnaires' disease The bacterium Legionella pneumophila is responsible for most cases of Legionnaires' disease. Outdoors, Legionella bacteria survive in soil and water, but rarely cause infections. Indoors, though, Legionella bacteria can multiply in all kinds of water systems hot tubs, air conditioners and mist sprayers in grocery store produce departments. Although it's possible to contract Legionnaires' disease from home plumbing systems, most outbreaks have occurred in large buildings, perhaps because complex systems allow the bacteria to grow and spread more easily.

85 Most people become infected when they inhale microscopic water droplets containing legionella bacteria. This might be the spray from a shower, faucet or whirlpool, or water dispersed through the ventilation system in a large building. Outbreaks have been linked to a range of sources, including: Hot tubs and whirlpools on cruise ships Cooling towers in air conditioning systems Decorative fountains Swimming pools Physical therapy equipment Water systems in hotels, hospitals and nursing homes

86 Not everyone exposed to legionella bacteria becomes sick. You're more likely to develop the infection if you: Smoke. Smoking damages the lungs, making you more susceptible to all types of lung infections. Have a weakened immune system as a result of HIV/AIDS or certain medications, especially corticosteroids and drugs taken to prevent organ rejection after a transplant. Have a chronic lung disease such as emphysema or another serious condition such as diabetes, kidney disease or cancer. Are 65 years of age or older. Have a job maintaining the cooling towers in air conditioning systems. Legionnaires' disease is a sporadic and local problem in hospitals and nursing homes, where germs may spread easily and people are vulnerable to infection.

87 Legionnaires' disease acquired its name in July 1976 when an outbreak of pneumonia occurred among people attending a convention of the American Legion at the Bellevue-Stratford Hotel in Philadelphia. On January 18, 1977 the causative agent was identified as a previously unknown strain of bacteria, subsequently named Legionella. Some people can be infected with the Legionella bacteria and have only mild symptoms or no illness at all. Outbreaks of Legionnaires' disease receive significant media attention. However, this disease usually occurs as single, isolated cases not associated with any recognized outbreak. When outbreaks do occur, they are usually in the summer and early autumn, though cases may occur at any time of year. Most infections occur in those who are middle-age or older.

88 Q fever Query fever Q fever is found around the world and is caused by the bacteria Coxiella burnetii. The bacteria infects sheep, goats, cattle, dogs, cats, birds, rodents, and ticks, as well as some other animals. Infected animals shed this bacteria in: Birth products Feces Milk Urine

89 Humans usually get Q fever by breathing in contaminated droplets released by infected animals. Drinking raw milk has also caused infection in rare cases. People at highest risk for this infection are: Farmers Laboratory workers who work with Coxiella burnetii Sheep and dairy workers Veterinarians People at highest risk include those with heart valve problems or weakened immune systems.

90 It usually takes about 20 days after exposure to the bacteria for symptoms to occur. Most cases are mild, yet some severe cases have been reported. Common symptoms of acute Q fever may include: Dry cough Fever Headache Joint pain Muscle pains

91 The main treatment for Q fever is with antibiotics. For early-stage (acute) Q fever, doxycycline is the recommended antibiotic. If you have the infection for more than 6 months, it is called chronic Q fever. Your doctor may prescribe both doxycycline and hydroxychloroquine. You may need to take antibiotics for several months or years.

92 Cholera V. cholerae Cholera is caused by the bacterium Vibrio cholerae. The bacteria releases a toxin that causes increased release of water from cells in the intestines, which produces severe diarrhea. Cholera occurs in places with poor sanitation, crowding, war, and famine. Common locations for cholera include: Africa Asia India Mexico South and Central America

93 People get the infection by eating or drinking contaminated food or water. A type of vibrio bacteria also has been associated with shellfish, especially raw oysters. Risk factors include: Exposure to contaminated or untreated drinking water Living in or traveling to areas where there is cholera

94 Symptoms Abdominal cramps Dry mucus membranes or mouth Dry skin Excessive thirst Glassy or sunken eyes Lack of tears Lethargy Low urine output Nausea Rapid dehydration Rapid pulse (heart rate) Sunken "soft spots" (fontanelles) in infants Unusual sleepiness or tiredness Vomiting Watery diarrhea that starts suddenly and has a "fishy" odor Note: Symptoms can vary from mild to severe.

95 Antibiotic treatments for one to three days shorten the course of the disease and reduce the severity of the symptoms. People will recover without them, however, if sufficient hydration is maintained. Doxycycline is typically used first line, although some strains of V. cholerae have shown resistance. Testing for resistance during an outbreak can help determine appropriate future choices. Other antibiotics proven to be effective include cotrimoxazole, erythromycin, tetracycline, chloramphenicol, and furazolidone. Fluoroquinolones, such as norfloxacin, also may be used, but resistance has been reported.


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