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Match each organism to the most likely method of transmission:

Which of the following organisms is a definitive pathogen?

Case Study 1: This 19-year-old student was in his usual state of health until the evening prior to admission, when he went to bed with a headache. He told his mother that he felt feverish, and on the following morning his mother found him in bed, moaning and lethargic. He was brought to the emergency room, where he appeared toxic and drowsy, but oriented. His temperature was 40C, his heart rate was 126/min., and his blood pressure was 100/60 mm Hg. He had an impressive purpuric rash (bruise-like), not blanching, most prominent on his trunk, legs and wrists. A gram stain of the material taken from one of the patient’s skin lesions showed gram-negative diplococci. His white blood cell count was 26,000/ml (high) with 25% band forms (high). The platelet count was 80,000/ml (low). Blood cultures were obtained and the patient was begun on intravenous Ceftriaxone. Blood cultures subsequently grew the organism seen on the gram stains of the lesions. Case Study 1 Question 5:  What virulence factor of this organism is probably responsible for the purpuric rash?

A 4-year-old was bitten on her hand by her pet cat. Two days later, the bite area was swollen and had some drainage. A Gram’s stain of the pus revealed small gram-negative coccobacilli. The most likely identity of this organism is:

Assuming the teacher was unwilling to change the common pencil box practice, what is the most effective way to break the chain of infection caused by this classroom behavior?

Case Study 4:   An 8-year-old female was brought to the walk-in clinic by her mother. For the last three days she has been complaining that her ear has been bothering her and last night she developed a low fever.  Her vaccinations are all up to date, her medical history is unremarkable, and she has had no previous illness; she is a healthy girl. Her mother mentions that she is very active in sports, alternating between swimming and soccer competitions every weekend. The physician collected a culture and stat gram stain of the outer ear canal. The gram stain showed many white blood cells and gram-negative bacilli.  The physician then gave the girl antibiotic drops to use twice a day for seven days without waiting for the culture results. Case Study 4 Question 1:  What infection does the little girl have?

Within 5 hours of returning home from lunch at your favorite all-you-can-eat buffet restaurant you feel very sick and are vomiting. The most likely cause is:

Which of the following organisms would be suitable as positive and negative controls, respectively, for the oxidase test?

An iInfection with this organism is associated with human bite wounds:

A non-fermentative, gram negative bacillus was isolated from the sputum of a patient with cystic fibrosis. The colonies were green on SBAP and MAC, oxidase positive, and had a characteristic grape-like odor. What is the most likely identity of this organism?