What is the most appropriate method for diagnosis of listeriosis

Correct Answer: A

Rationale: The correct answer is A: cultivating on artificial media and biochemical identification. This method is appropriate for diagnosing listeriosis because it allows for the isolation and growth of Listeria species on selective media, followed by biochemical tests to confirm the identity. Serological diagnosis with ELISA (choice B) is not as specific for Listeria and may yield false positives. Choice C, serological diagnosis with agglutination hype Widal, is not typically used for listeriosis diagnosis. Cultivating in cell cultures (choice D) is not the primary method for diagnosing listeriosis as it is less specific compared to cultivating on artificial media and biochemical identification.

Correct Answer: A

Rationale: The correct answer is A: CMV (Cytomegalovirus). CMV is the most common congenital infection worldwide due to its high prevalence and ability to be transmitted from mother to fetus during pregnancy. It can lead to serious complications such as hearing loss, developmental delays, and vision problems in newborns. Listeria monocytogenes (B) is a foodborne pathogen, not typically associated with congenital infections. Rubella Virus (C) can cause congenital rubella syndrome but is less common globally compared to CMV. Syphilis (D) can also be transmitted from mother to fetus, but its prevalence and impact on congenital infections are lower compared to CMV.

Correct Answer: C

Rationale: The correct answer is C: To determine the antibiotic susceptibility of microorganisms. PCR is not suitable for determining antibiotic susceptibility as it is a technique used to amplify DNA/RNA, not to test for antibiotic resistance. To prove latent infection (A), PCR can be used to detect low levels of pathogens. For rapid diagnosis of infectious diseases (B), PCR is commonly used due to its sensitivity and specificity. To demonstrate DNA and RNA molecules (D), PCR is ideal as it can amplify and detect specific sequences. Therefore, choice C is incorrect as PCR is not designed for determining antibiotic susceptibility.

Correct Answer: C

Rationale: Rationale: Choice C is correct because Staphylococcus epidermidis, Escherichia coli, and Enterococcus spp. are common causative agents of nosocomial infections due to their presence on the skin, in the gut, and in healthcare settings. S. aureus and L. monocytogenes (Choice A) are also important pathogens but are less common in nosocomial infections. Enterobacteriaceae (Choice B) are a large family of bacteria that can cause infections but are not as commonly associated with nosocomial infections compared to the organisms in Choice C. The correct answer (Choice C) encompasses pathogens commonly found in healthcare settings, making it the most suitable option.

Correct Answer: B

Rationale: The correct answer is B: Biological oxidation. Haematrophic bacteria obtain energy through biological oxidation, where they break down organic compounds to generate ATP for cellular processes. This process involves the transfer of electrons from the substrate to an electron transport chain to produce energy. Heat production (A) is a byproduct of metabolism, not the primary way to obtain energy. In biosynthetic reactions (C), energy is utilized rather than generated. Cultivation in culture media (D) is a method of growing bacteria but does not directly provide energy. Therefore, the correct answer is B as it aligns with the metabolic process of haematrophic bacteria.