A pregnant woman at 28 weeks gestation is being counseled on preventing food-borne listeriosis. Which of the following food items is considered safe for her to consume without special preparation such as heating?
A 16-year-old girl develops an abrupt onset of high fever, shaking chills, and severe myalgias, especially in her calves and back, one week after a recreational trip involving swimming in a freshwater lake. Physical examination reveals bilateral conjunctival suffusion without any purulent exudate. Her illness most likely follows a course best described as?
A physician is reviewing an outbreak report of a severe respiratory illness. The investigation revealed that most cases occurred through human-to-human transmission within overcrowded emergency departments and were linked to a patient who had recently traveled in the Arabian Peninsula. These epidemiological features are most characteristic of which coronavirus?
An unvaccinated 4-month-old infant is hospitalized with severe, dehydrating rotavirus gastroenteritis. The infant’s 2-year-old sibling, who completed the oral rotavirus vaccine series on schedule, experienced a brief, mild diarrheal illness the week before the infant became sick. What is the most likely genetic mechanism explaining the severe illness in the unvaccinated infant?
An 11-year-old hematopoietic stem cell transplant recipient develops chronic watery diarrhea and weight loss. Stool studies are negative for common pathogens. Special staining of a stool sample reveals very small (1-5 µm) spores. The infection is identified as Enterocytozoon bieneusi. What is the expected efficacy of albendazole for this specific species of microsporidia?
A 12-year-old with systemic lupus erythematosus on chronic corticosteroid therapy is diagnosed with pulmonary nocardiosis. Given this diagnosis in an immunocompromised host, what is the most important next step in the diagnostic workup?
A 9-year-old boy living in a suburban area of Southern California presents in May with a 5-day history of fever, headache, and a maculopapular rash on his trunk. His parents report a recent problem with flea infestation from their opossum-frequenting backyard. Labs show mild thrombocytopenia and elevated transaminases. His illness is most likely transmitted by which vector?
A 6-year-old boy living in Ohio presents in late summer with a 2-day history of fever and headache that has progressed to a generalized seizure. His home has a wooded backyard with many old trees. What is the most likely pathogen?
During a routine follow-up visit for a 7-year-old child with stable, untreated HIV infection, the physician notes several clinical findings. The child’s CD4+ T-lymphocyte count has remained relatively stable over the past year. Which of the following clinical findings is most associated with a slower progression of HIV disease and a better prognosis in children?
A 7-year-old child has recurrent, symptomatic enterobiasis despite appropriate treatment of the entire family and meticulous hygiene. The most common complaint is perianal itching, but the mother also reports intermittent diarrhea. Stool studies for other common parasites are negative. What other infection has been described in association with Enterobius vermicularis infection and could be contributing to the diarrheal symptoms?
