Respiratory Viral Pathogens Laboratory

1. Referral diagnostic services

The laboratory provides referral testing for respiratory viral infections using molecular methods. The testing activities include:

• Detection and typing of Influenza A and Influenza B viruses.
• Subtyping of Influenza A(H1N1)pdm09 and Influenza A(H3N2) viruses and other subtypes
• Lineage determination of Influenza B viruses, wherever indicated.
• Detection of Respiratory Syncytial Virus A and B, SARS-CoV-2, adenovirus, human metapneumovirus and other respiratory viruses under the approved laboratory scope.
• Testing of respiratory specimens received from hospitals, surveillance sites and other referring institutions in accordance with prescribed specimen-referral requirements.
• Expansion of molecular diagnostic capacity: the Division is strengthening its molecular diagnostic capacity for selected respiratory and clinically important viral infections. Molecular testing for *Mycoplasma pneumoniae* and herpes simplex virus types 1 and 2 is under development.

2. Diagnostic services for selected congenital and opportunistic viral infections

The laboratory undertakes testing for selected viral infections of importance in congenital disease and immunocompromised patients, including:

• Serological testing for rubella virus, cytomegalovirus and herpes simplex viruses 1 and 2
• Molecular detection of cytomegalovirus.
• CMV DNA viral-load testing in appropriate clinical specimens.

3. Influenza and respiratory-virus surveillance

The Division supports laboratory-based surveillance of influenza and other respiratory viruses through:

• Testing of specimens collected from cases of influenza-like illness and severe acute respiratory infection.
• Laboratory surveillance for circulating influenza types, subtypes and lineages.
• Surveillance for RSV, adenovirus, SARS-CoV-2 and other respiratory viral pathogens.
• Compilation, analysis and interpretation of laboratory surveillance data.
• Communication of laboratory findings to the concerned surveillance and public-health authorities.

4. Coordination of the IDSP Influenza Surveillance Laboratory Network

The Division functions as the nodal laboratory for the IDSP Influenza Surveillance Laboratory Network. Its activities include:

• Technical coordination with the network laboratories.
• Compilation and analysis of laboratory surveillance data received from the network.
• Harmonization of laboratory quality testing and reporting practices
• Technical guidance on specimen collection, transport, testing algorithms and interpretation of results.

5. Outbreak investigation and public-health emergency response

The Division provides laboratory support during outbreaks and public-health emergencies involving respiratory viruses. The activities include:

• Testing of clinical specimens collected during suspected outbreaks.
• Support for investigation of seasonal and zoonotic influenza, including suspected avian-influenza events.
• Laboratory preparedness for emerging respiratory viral pathogens.
• Technical coordination with IDSP, State Surveillance Units, ICMR-NIV and other concerned institutions.
• Timely communication of laboratory results for appropriate public-health action.

6. Influenza virus characterization

Influenza-positive specimens are selected, as appropriate, for further characterization. Activities include:

• Referral of selected specimens or amplification products to designated sequencing facilities.
• Support for analysis of genetic variation, circulating influenza strains and their relationship with reference or vaccine strains based on sequencing results.

Whole-genome sequencing and advanced genomic analysis are undertaken through designated facilities or collaborative arrangements, wherever required.

7. Training and capacity building

The Division organizes and supports for capacity-building activities related to:

• Collection, packaging, storage and transport of respiratory specimens.
• Molecular diagnosis, typing and subtyping of influenza and other respiratory viruses.
• Laboratory biosafety, quality assurance and interpretation of test results.
• Influenza surveillance and outbreak investigation.
• Training and technical orientation of laboratory personnel, surveillance officers and healthcare professionals.

8. Data analysis, technical inputs and knowledge dissemination

The Division undertakes laboratory surveillance data analysis relating to influenza and other respiratory viruses. It provides subject-specific technical and scientific inputs for:

• CD Alert publications relating to respiratory viral diseases and tuberculosis.
• Articles and updates published in the NCDC Newsletter.
• Technical reports, advisories, guidelines and training materials.
• Responses to official references and public-health communications concerning respiratory viruses and tuberculosis.
• Technical discussions and collaborative activities with IDSP, ICMR, WHO and other public-health institutions.

9. Tuberculosis Laboratory

The Tuberculosis Laboratory undertakes:

• Detection of acid-fast bacilli by Ziehl–Neelsen smear microscopy.
• Rapid molecular detection of Mycobacterium tuberculosis and rifampicin resistance using chip based or other approved molecular platforms as per National tuberculosis elimination programme
• Testing of appropriate pulmonary and extrapulmonary clinical specimens in accordance with the approved laboratory scope.
• Maintenance of laboratory quality assurance, biosafety and testing records.
• Technical support and capacity-building activities related to laboratory diagnosis of tuberculosis.
• Real-time entry of testing data, results and patient details on Nikshay portal .
• Expansion of TB diagnostic capacity: Division is strengthening its testing capacity for Mycobacterium species and for drug resistant strains.