Microbiology An Introduction Tortora Test Bank

Correct Answer: A

Rationale: The correct answer is A: BCG (Bacille Calmette-Guerin). BCG is the vaccine used for tuberculosis prevention, not only for newborns but also for older children and adults. BCG helps in protecting against severe forms of tuberculosis in infants. Diphteria and tetanus toxoids and pertussis vaccine (choice B) is for protection against diphtheria, tetanus, and pertussis, not tuberculosis. Diphtheria and tetanus anatoxin vaccine (choice C) provides protection against diphtheria and tetanus, not tuberculosis. Adsorbed diphtheria vaccine (choice D) is specifically for diphtheria, not tuberculosis. Therefore, the correct choice is A as it is the only vaccine related to tuberculosis prevention.

Correct Answer: D

Rationale: The correct answer is D because polio viruses are primarily found in the gastrointestinal tract and respiratory secretions. Feces, nasopharyngeal swabs, and cerebrospinal fluid are the most suitable materials for isolating polio viruses due to their presence in these body fluids. Feces contain the virus shed from the intestines, nasopharyngeal swabs collect respiratory secretions where the virus may be present, and cerebrospinal fluid is important for detecting the virus in cases of neurological complications. Choices A and B include irrelevant body fluids that are not typically associated with polio virus transmission. Option C is too limited as the virus can also be present in respiratory secretions and cerebrospinal fluid, not just feces.

Correct Answer: B

Rationale: The correct answer is B: Acute purulent lymphadenitis. The symptoms described indicate an acute bacterial infection of the lymph nodes. The presence of painful lymph nodes, erythema, and shiny appearance of the skin overlying the nodes suggest an inflammatory process. The rise in temperature and frequent pulse indicate an active infection. The white-coated tongue may be a sign of systemic involvement. The shaky gait may indicate systemic toxicity. Bubonic plague (A) presents with buboes, not just painful lymph nodes. Lymphogranulomatosis (C) is a type of lymphoma and would not present with these acute bacterial infection symptoms. Anthrax (D) typically presents with a black eschar and is less likely in this context.

Correct Answer: A

Rationale: The correct answer is A: Clostridium perfringens. This is because Clostridium perfringens is a Gram-positive rod bacterium that forms terminal spores. It is commonly associated with deep tissue infections and can cause gas gangrene. Bacillus anthracis (B) causes anthrax and does not typically form spores at the terminal end. Clostridium tetani (C) causes tetanus and Bacillus cereus (D) is more commonly associated with food poisoning. In this case, the presence of terminal spores along with the clinical presentation of a deep tissue infection points towards Clostridium perfringens as the most likely causative agent.

Correct Answer: B

Rationale: The correct answer is B: adolescents. Infectious mononucleosis is commonly caused by the Epstein-Barr virus, which is transmitted through saliva. Adolescents are more likely to engage in activities like kissing and sharing drinks, increasing the chances of virus transmission. Infants have maternal antibodies for protection, young adults may have developed immunity, and the elderly have had more exposure to the virus and may have built immunity over time.