Techniques for Diagnosing Influenza Virus Infections
Diagnosis of influenza virus infections can be done using some of the following techniques:
A. Western blot and Southern blot
B. Northern blot and western blot
C. ELISA and RT-PCR
D. PCR and electron microscopy
Choose the combination of techniques that correctly lists the detection methods.
(1) A and B only
(2) C and D only
(3) B and C only
(4) A and D only
The correct answer is (2) C and D only – ELISA and RT-PCR and PCR and electron microscopy are widely used for diagnosing influenza virus infections.
✅ Correct Answer: (2) C and D only
- ELISA (Enzyme-Linked Immunosorbent Assay) – Detects influenza virus antigens or antibodies.
- RT-PCR (Reverse Transcription Polymerase Chain Reaction) – Detects influenza virus RNA with high sensitivity and specificity.
- PCR (Polymerase Chain Reaction) – Amplifies viral DNA for accurate diagnosis.
- Electron Microscopy – Visualizes the virus structure directly.
Explanation of Techniques Used for Diagnosing Influenza Virus
1. ELISA (Enzyme-Linked Immunosorbent Assay)
- ELISA is an immunological technique used to detect specific antigens or antibodies.
- Process:
- Sample (blood, respiratory secretion) is added to a plate coated with specific antibodies.
- If the antigen (influenza virus) is present, it binds to the antibodies.
- A secondary antibody conjugated with an enzyme is added.
- A color change occurs upon substrate addition, indicating the presence of the virus.
✔️ High sensitivity and specificity
✔️ Rapid and cost-effective
✔️ Commonly used for rapid influenza testing
2. RT-PCR (Reverse Transcription Polymerase Chain Reaction)
- RT-PCR is a molecular technique used to detect viral RNA.
- Process:
- Viral RNA is extracted from the sample.
- Reverse transcriptase converts RNA into complementary DNA (cDNA).
- PCR is performed using influenza-specific primers.
- Amplified DNA is detected using fluorescence or electrophoresis.
✔️ Highly sensitive and specific
✔️ Capable of detecting low viral loads
✔️ Used for subtyping and identifying specific influenza strains
3. PCR (Polymerase Chain Reaction)
- PCR amplifies viral DNA for detection and analysis.
- Although influenza is an RNA virus, PCR can be used after reverse transcription to convert RNA to cDNA.
- PCR helps in:
- Identifying genetic variations in influenza strains
- Detecting drug-resistant mutations
- Epidemiological studies
✔️ High sensitivity
✔️ Rapid detection
✔️ Useful for identifying novel strains
4. Electron Microscopy
- Electron microscopy provides direct visualization of the virus.
- Process:
- Viral particles are isolated from the sample.
- Samples are fixed and stained.
- High-resolution imaging is performed using an electron microscope.
✔️ Provides structural details of the virus
✔️ Useful for identifying morphological variations in different strains
✔️ Less sensitive for routine diagnostics but valuable for research
Incorrect Techniques
❌ 1. Western Blot
- Western blot is used for detecting proteins, not viral RNA or DNA.
- It detects antibodies against viral proteins, which may indicate past infection but is not suitable for direct virus detection.
❌ 2. Southern Blot
- Southern blot is used for detecting DNA, not RNA.
- Influenza virus is an RNA virus, so Southern blotting is not applicable.
Why ELISA, RT-PCR, PCR, and Electron Microscopy Are Correct
| Technique | Type | Target | Suitable for Influenza Detection |
|---|---|---|---|
| ELISA | Immunological | Antigen/Antibody | ✅ Yes |
| RT-PCR | Molecular | RNA | ✅ Yes |
| PCR | Molecular | DNA (cDNA) | ✅ Yes |
| Electron Microscopy | Imaging | Viral Particles | ✅ Yes |
| Western Blot | Protein Analysis | Protein | ❌ No |
| Southern Blot | DNA Analysis | DNA | ❌ No |
Applications of Diagnostic Techniques for Influenza
✅ 1. Clinical Diagnosis
- RT-PCR and ELISA are widely used in hospitals and diagnostic labs for rapid influenza diagnosis.
- PCR is essential for confirming the subtype of the virus.
✅ 2. Epidemiological Surveillance
- PCR is used for tracking the spread of influenza strains.
- ELISA helps in rapid screening during outbreaks.
✅ 3. Vaccine Development
- Electron microscopy provides insights into viral structure for vaccine design.
- RT-PCR and PCR help in identifying antigenic shifts and drifts in influenza strains.
✅ 4. Drug Resistance Monitoring
- PCR and sequencing identify mutations linked to antiviral resistance.
- RT-PCR helps in monitoring emerging resistant strains.
Why Option (2) is Correct
| Option | Techniques | Explanation | Correct/Incorrect |
|---|---|---|---|
| (1) A and B only | Western blot and Northern blot | Western blot detects proteins; Northern blot detects RNA but not suitable for clinical diagnosis. | ❌ Incorrect |
| (2) C and D only | ELISA, RT-PCR, PCR, and electron microscopy | ELISA and RT-PCR directly detect viral proteins or RNA; PCR and electron microscopy confirm viral identity. | ✅ Correct |
| (3) B and C only | Northern blot and ELISA | Northern blot is not used for routine viral diagnosis. | ❌ Incorrect |
| (4) A and D only | Western blot and PCR | Western blot is not suitable for direct virus detection. | ❌ Incorrect |
Summary
- ELISA – Detects influenza antigens/antibodies
- RT-PCR – Detects influenza RNA
- PCR – Amplifies viral DNA (cDNA)
- Electron Microscopy – Visualizes influenza virus particles
79 Comments
Nisha
March 17, 2025Done
Arushi
March 17, 2025👍👍
Suman bhakar
March 20, 2025✅
Kajal
August 22, 2025Option c n d means ELISA and RT -PCR, PCR n Electron microscopy
Kirti agarwal
August 20, 2025Done
Savita Garwa
August 20, 2025Answer 2 c or d
Pooja Sharma
August 22, 2025Done
Pooja Sharma
August 22, 2025Done ✅
Vijay Marmat
August 20, 2025Elisa and reverse-transcription
Polymerase chain reaction and electron microscope ✔️ 👍
Mahima Sharma
August 22, 2025Pcr and elisa reverse transcription
Neelam Sharma
August 20, 2025ELISA detect influenza antigen/antibody
Rt PCR detect influenza RNA
PCR amplify Viral DNA
Electron Microscopy visualization influenza virus particles
Diksha Chhipa
August 20, 2025Done
Mahima Sharma
August 24, 2025Rt.pcr and elisa reverse transcription
Priti khandal
August 20, 2025Elisa and rt pcr and pcr and electron microscopy
Dipti Sharma
August 20, 2025ELISA AND RT PCR
Tanvi Panwar
August 20, 2025Done
Parul Yadav
August 20, 2025ELISA, RT- PCR and PCR are helpful in diagnosis of influenza virus infection. Electron Microscopy is also helpful in studying the viral structure for the research.
Priya khandal
August 20, 2025Rtpcr elisa and pcr electro microscopy
Mitali saini
August 21, 2025The correct answer is (2) C and D only – ELISA and RT-PCR and PCR and electron microscopy are widely used for diagnosing influenza virus infections.
Sheikh Aleen
August 21, 2025ELISA , RT-PCR , PCR and electron microscopy
Deepika Sheoran
August 21, 2025Option b is correct answer
Because ELISA detect influenja.
RT PCR detect RNA.
PCR amplification DNA.
Electron microscopy visualization influenja virus particles.
Himanshi
August 21, 2025Elisha and rt-pcr
Pcr and electomicrospy
Himanshi
August 21, 2025Elisha, rt-pcr
Pcr and electomicrospy
Bharti Yadav
August 21, 2025ELISA: Detects viral antigens or antibodies.
RT-PCR: Detects viral RNA with high sensitivity and specificity.
PCR: Amplifies viral DNA for diagnosis. Electron Microscopy: Visualizes virus structure directly.
Option b is correct.
Sakshi
August 21, 2025option B is correct
ELISAor RtPcr directly detect viral protein and rna and pcr and electron microscope confirm viral identity
Sonam Saini
August 21, 2025B is right answer
Yashika Choudhary
August 22, 2025Rt pcr mei rna se dna bna ke aage proceed krn h
Yashika Choudhary
August 22, 2025Rt pcrrrrrrrr is rna se dna
shruti sharma
August 22, 2025C and D
Aman Choudhary
August 22, 2025Elisa and reverse-transcription
Polymerase chain reaction and electron microscope
Gayatri
August 23, 2025Answer is 2 c or d
Niti Tanwar
August 22, 2025Elisa and rt- pcr and electron microscopy
Kirti agarwal
August 22, 2025Option c and d only
Ankita Pareek
August 23, 2025Elisa ,RT PCR,pcr and electron microscope
phalguni Prakash
August 22, 20252 option
Simran Saini
August 22, 2025C and D only.
ELISA and RT-PCR.
PCR and electron microscopy.
Kajal
August 22, 2025Option c n d means ELISA and RT -PCR, PCR n Electron microscopy
Anjali
August 23, 2025C and D is correct answer.
Priyanka Choudhary
August 23, 2025Right answer is 2nd(c and d)
ELISA and RT-PCR
D. PCR and electron microscopy
Phalguni
August 23, 20252
yashika
August 23, 2025Rt pcr and elisa for virus cause it has dna
Priya dhakad
August 23, 2025Option 2nd correct ELISA and RT-PCR directly detect viral proteins or RNA;PCR and electron microscopy confirm viral identity.
Varsha Tatla
August 23, 2025ELISA detection antigen nd antibodies infaction,nd RT PCR
Akshita Jangid
August 23, 2025ELISA, RT-PCR, and PCR used for diagnosing influeza virus
Aafreen Khan
August 23, 2025(2) C and D only
ELISA- Detects influenza virus antigens or antibodies and Rt-PCR has High sensitivity and high specificity
PCR Amplifies viral DNA for accurate diagnosis and Electron Microscopy Visualizes the virus
Ankita Pareek
August 23, 2025Elisa ,RT PCR,pcr and electron microscope
Devika
August 24, 20252nd is correct ELISA,rtpcr,electron microscopy,pcr
Soniya Shekhawat
August 23, 2025Elisa and RT PCR, PCR and electron microscope is detected influenza virus .
Santosh Saini
August 24, 2025ELISA to detect antigen and antibodies of influenza virus, RT PCR to detect RNA , PCR and Electron microscopy to detect DNA of influenza virus
Divya Mandhania
August 24, 2025C and d is right answer
Khushi Vaishnav
August 24, 2025Elisa ,RT PCR,pcr and electron microscope
Alec
August 24, 2025option 2 is correct C and D
Arushi Saini
August 24, 2025Elisa ,rt-pcr and electron microscopy
Gunjan Singh
August 24, 2025RT PCR is a sensitive and accurate method for influenza diagnosis. So the correct option will be 2nd i.e. C and D.
Avni
August 24, 2025ELISA and RT-PCR ,PCR and electron microscopy
Pooja
August 24, 2025ELISA and RT-PCR and PCR and electron microscopy are widely used for diagnosing influenza virus infections.
Devika
August 24, 20252nd is correct ELISA,rtpcr,electron microscopy,pcr
Aakanksha Sharma
August 24, 2025RT PCR & ELISA
AKANKSHA RAJPUT
August 24, 2025Elisa and rt-pcr are used to diagnose influenza virus.
Sneha Kumawat
August 24, 2025ELISA viral antigen ya patient ki antibody ko detect krta h RT PCR viral rna ko detect krta h electron microscopy se virus particles ko directly dekh skte h
Sakshi yadav
August 24, 2025ELISA and RT-PCR and PCR and electron microscopy
Kashish yadav
August 25, 2025Ok sir
MOHIT AKHAND
August 25, 2025Done sir ✅
Kajal
August 25, 2025Option c and D only
Bhavana kankhedia
August 26, 2025C and D
Muskan Yadav
August 26, 2025ELISA and RT-PCR and PCR and electron microscopy are used for diagnosing influenza virus infections.
Anju
August 26, 2025Ans: 2(c and d )
Neha Yadav
August 27, 2025Influenza virus infection detection by ELISA (used for rapid influenza testing ) ,RT – PCR ( Detect RNA with high specificity ) ,PCR ( Amplify the viral DNA ) , Electron microscopy ( visualization the virus str directly )
Anjali
August 28, 2025Elisha and rt-pcr
Pcr and electomicrospy
Kanica Sunwalka
August 28, 2025done
Yashika Rajawat
August 29, 2025This solution is awesome not because it’s provides solution but also provide explanation why other options are not correct , that’s amazing
Shriyanshi verma
August 30, 2025Option c n d means ELISA and RT -PCR, PCR n Electron microscopy
anjani sharma
August 30, 2025Elisa and reverse-transcription
Polymerase chain reaction and electron microscope
Shobha sharma
August 31, 2025Option c n d means ELISA and RT -PCR, PCR n Electron microscopy
Sona
August 31, 2025C and D option means ELISA and RT PCR and PCR and electron microscopy both used for diagnosis virus infection
Anisha jakhar
August 31, 2025Correct techniques are RT-PCR, ELIZA, PCR and electron microscope
Saniya Jangid
August 31, 2025👍 done
Shobha Kanwar
August 31, 2025The correct answer is (2) C and D only – ELISA and RT-PCR and PCR and electron microscopy
Roopal Sharma
August 31, 2025ELISA and Rt pcr