Evidence map›Paper›PMID 42021871›Full record

ArticleThe Lancet regional health. Southeast Asia2026

Burden and risk factors of influenza-associated acute respiratory infections among older adults in India: a multicentric community-based surveillance (2018-2023).

Prabu Rajkumar, Girish Kumar Chethrapilly Purushothaman, Ritvik Amarchand, Aslesh Ottapura Prabhakaran, Rakesh Kumar, Suman Kanungo, Sumit Dutt Bhardwaj, Varsha Potdar, Alok Kumar Chakrabarty, Avinash Choudekar and 22 more

Abstract read
In one paragraph

Article in The Lancet regional health. Southeast Asia, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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2 · The registry

The trial behind it

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3 · Its place in the literature

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0 citing papers in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

32 authors.

Prabu RajkumarICMR National Institute of Epidemiology, Chennai, India.
Girish Kumar Chethrapilly PurushothamanICMR National Institute of Epidemiology, Chennai, India.
Ritvik AmarchandCentre for Community Medicine, All India Institute of Medical Sciences, New Delhi, India.
Aslesh Ottapura PrabhakaranInfluenza Program, US Centers for Disease Control and Prevention, New Delhi, India.
Rakesh KumarCentre for Community Medicine, All India Institute of Medical Sciences, New Delhi, India.
Suman KanungoICMR National Institute for Research in Bacterial Infections, Kolkata, India.
Sumit Dutt BhardwajICMR National Institute of Virology, Pune, India.
Varsha PotdarICMR National Institute of Virology, Pune, India.
Alok Kumar ChakrabartyICMR National Institute for Research in Bacterial Infections, Kolkata, India.
Avinash ChoudekarDepartment of Microbiology, All India Institute of Medical Sciences, New Delhi, India.
Mohan VinothICMR National Institute of Epidemiology, Chennai, India.
Giridara Gopal ParameswaranCentre for Community Medicine, All India Institute of Medical Sciences, New Delhi, India.
Uttaran BhattacharyaICMR National Institute for Research in Bacterial Infections, Kolkata, India.
Rohan GhugeICMR National Institute of Virology, Pune, India.
Mani MohanrajICMR National Institute of Epidemiology, Chennai, India.
Shivram DhakadDepartment of Microbiology, All India Institute of Medical Sciences, New Delhi, India.
Aashish ChoudharyDepartment of Microbiology, All India Institute of Medical Sciences, New Delhi, India.
Kangusamy BoopathiICMR National Institute of Epidemiology, Chennai, India.
Premkumar HarishICMR National Institute of Epidemiology, Chennai, India.
Prerna MalikCentre for Community Medicine, All India Institute of Medical Sciences, New Delhi, India.
Prema ShanmugasundaramICMR National Institute of Epidemiology, Chennai, India.
Krishna SardaICMR National Institute for Research in Bacterial Infections, Kolkata, India.
Naziya Khudoos BabuICMR National Institute of Epidemiology, Chennai, India.
Priyanka ChakrabartyICMR National Institute for Research in Bacterial Infections, Kolkata, India.
Sivanandam Banu PriyaICMR National Institute of Epidemiology, Chennai, India.
Anusha HindupurICMR National Institute of Epidemiology, Chennai, India.
Kathryn LafondInfluenza Division, US Centers for Disease Control and Prevention, Atlanta, GA, USA.
Eduardo Azziz-BaumgartnerInfluenza Division, US Centers for Disease Control and Prevention, Atlanta, GA, USA.
Kathrine R TanInfluenza Division, US Centers for Disease Control and Prevention, Atlanta, GA, USA.
Siddhartha SahaInfluenza Program, US Centers for Disease Control and Prevention, New Delhi, India.
Lalit DarDepartment of Microbiology, All India Institute of Medical Sciences, New Delhi, India.
Anand KrishnanCentre for Community Medicine, All India Institute of Medical Sciences, New Delhi, India.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Background: Community-level estimates of influenza burden among older adults are important to inform prevention strategies, but limited data exist in India. This study determines the incidence and associated risk factors of influenza-associated acute respiratory infection (ARI) among older adults (age ≥ 60 years) using surveillance data across four community-based sites in India during 2018-2023. Methods: Acute upper respiratory (AURI) and lower-respiratory infections (ALRI) were identified through weekly domiciliary surveillance by trained healthcare workers among older adults residing in four community-based surveillance sites in India. Nasal and throat swabs were collected from all individuals with ALRI episodes and from a subset of individuals with AURI episodes for influenza RT-PCR testing. Predominant clades and subclades were detected by whole genome sequencing. Incidence rates per 1000 person-years of influenza-associated AURI and ALRI were calculated for pre-COVID-19 (July 2018-March 2020) and during COVID-19 pandemic (September 2020-March 2023) periods. Risk factors for influenza-associated ALRI were identified using Poisson regression. Findings: During the 19,914.2 person-years of follow-up, 23,576 AURI and 1952 ALRI episodes were identified. Influenza A accounted for 190 (73.1%) AURI and 140 (82.8%) ALRI episodes. Influenza A(H3N2), particularly subclade 3C.2a1b.2a predominated overall, though circulation patterns varied across sites and time periods. Incidence rates of influenza-associated AURI and ALRI were 39.2 and 8.5/1000 person-years respectively. AURI and ALRI incidence rates were higher in pre-COVID-19 (60.6 and 12.4/1000 person-years) than during the COVID-19 (25.1 and 5.9/1000 person-years) period. Factors associated with influenza ALRI included pre-COVID-19 and latter part of COVID-19 pandemic (2022-2023) periods, Chennai and Ballabgarh surveillance sites, age group 65-69 and greater than equal to 75 years, female sex, chronic respiratory disease, and presence of any disability. Interpretation: These findings highlight the burden of influenza-associated respiratory illness among older adults and has elucidated individual and household-level factors associated with severe disease. The results provide potential evidence to inform future prevention strategies including vaccination programmes prioritising older adults. Funding: This study was supported by National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC) through the cooperative agreement (U01IP001074) with AIIMS New Delhi.

Indexed as

AgedIndiaInfluenzaRespiratory tract infectionsRisk factorsSeasons

Identifiers

PMID42021871
PMCPMC13098438

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LicenceCC BY-NC-ND
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.