Which of the following is NOT used for the cultivation of viruses?

UPUMS Nsg officer-2023

Applied Microbiology & Infection control

Medium

Appeared in: UPUMS Nsg officer-2023

Explanation

Enrichment media are artificial, non-living nutrient solutions supplemented with substances like blood or serum to support the growth of nutritionally demanding (fastidious) bacteria.
Viruses are obligate intracellular parasites, meaning they lack their own metabolic machinery for replication and are completely dependent on the functions of a living host cell.
Because enrichment media do not contain living cells, viruses cannot replicate in them, making this method unsuitable for viral cultivation.

Option A: Tissue culture, or cell culture, is the most widely used method for cultivating viruses in modern virology labs.
Option B: Embryonated eggs are a classic and still relevant method for growing certain viruses, especially for vaccine production (e.g., influenza).
Option C: Animal inoculation was one of the first methods used to isolate and study viruses and is still used for specific purposes.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Virus Cultivation Methods as background academic context rather than a clinical decision trigger.
Understanding virus cultivation is fundamental for diagnosing viral infections, producing viral vaccines (e.g., influenza, measles), and for research into new antiviral drugs.
The choice of cultivation method depends on the specific virus being studied. For example, influenza is often grown in eggs for vaccine manufacturing, while herpes simplex virus is typically grown in cell culture for diagnostic testing.
What if? If a laboratory receives a throat swab to test for both Streptococcus (a bacterium) and Influenza (a virus), two different cultivation techniques would be required. The sample would be streaked on blood agar (an enriched medium) to grow the bacteria and also inoculated into a cell culture or embryonated egg to grow the virus.

How to Approach the Question

First, identify the keywords in the question: 'NOT used' and 'cultivation of viruses'.
The word 'NOT' signals that this is a negative question, meaning you must find the option that is an exception or does not fit.
Recall the fundamental biological characteristic of a virus: it is an obligate intracellular parasite. This is the key concept.
Evaluate each option based on this principle: Does the method provide living cells for a virus to infect?
Analyze the options: Tissue culture (living cells), embryonated eggs (living embryo), and animal inoculation (living animal) all provide the necessary living host environment.
Consider 'Enrichment media'. Recall that this is a nutrient broth used for bacteria. It is an artificial, non-living medium.

Concept Tested & Keywords

Concept Tested: Virus Cultivation Methods
Stem keywords: cultivation of viruses
Lead-in keywords: NOT
Negative lead-in flag: This question uses negative framing (NOT), requiring you to identify the method that is NOT used for virus cultivation.

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E6 Microbiology Essentials Sastry 4e Part 1 pp. 96-98, 48-50