SARS is.

SGPGI Nursing Officer-2023

Applied Microbiology & Infection control

Easy

Appeared in: SGPGI Nursing Officer-2023

Explanation

Severe Acute Respiratory Syndrome (SARS) is caused by SARS-coronavirus (SARS-CoV), which belongs to the Coronaviridae family.
Coronaviruses are characterized by having a single-stranded, positive-sense RNA genome.
The term 'positive-sense' means the viral RNA can be directly translated into protein by the host cell's machinery, similar to messenger RNA (mRNA).
This genetic makeup distinguishes it from DNA viruses and double-stranded RNA viruses.

Option B: Double-stranded RNA is the genetic material for viruses in the Reoviridae family, such as Rotavirus. Coronaviruses, including SARS-CoV, do not have a double-stranded genome.
Option C: SARS-CoV is an RNA virus. Single-stranded DNA (ssDNA) is the genome type for viruses in the Parvoviridae family, like Parvovirus B19.
Option D: SARS-CoV is an RNA virus. Double-stranded DNA (dsDNA) is found in viruses such as Herpesviridae (e.g., herpes simplex) and Poxviridae (e.g., smallpox).

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Viral classification based on genetic material (genome type) as background academic context rather than a clinical decision trigger.
Understanding that SARS is a highly contagious RNA virus transmitted by respiratory droplets dictates the stringent infection control protocols required in a clinical setting. Nurses must use N95 masks, eye protection, gowns, and gloves (droplet and contact precautions) to prevent nosocomial spread.
The rapid mutation rate of RNA viruses (due to less stable replication compared to DNA viruses) explains the emergence of new variants, which is a critical concept for understanding pandemics like COVID-19 (caused by SARS-CoV-2).
What if? If the pathogen were a dsDNA virus like Varicella-zoster (chickenpox), while airborne precautions are also needed, the treatment strategy would be different. Antivirals would target DNA polymerase (e.g., Acyclovir) instead of RNA-dependent processes. Also, a stable and effective vaccine is more readily developed for many DNA viruses.

How to Approach the Question

First, identify the key term in the question, which is 'SARS'.
Recall or deduce the classification of the SARS virus. SARS stands for Severe Acute Respiratory Syndrome, which is caused by a type of coronavirus.
Access your knowledge about the fundamental classification of viruses based on their genetic material: DNA vs. RNA, and single-stranded vs. double-stranded.
Place coronavirus into this classification. Coronaviruses are known to be RNA viruses.
Further specify whether they are single or double-stranded. Coronaviruses are single-stranded.
Based on this, select the option 'Single standard RNA Virus' and eliminate the other options related to DNA or double-stranded RNA.

Concept Tested & Keywords

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