India’s H1N1 Season Renews Focus on One Health as H5N1 Remains a Poultry Risk

India’s current seasonal H1N1 influenza activity is drawing renewed attention to the need for integrated One Health surveillance, particularly as highly pathogenic avian influenza A(H5N1) continues to circulate in poultry and wildlife. Recent evidence shows that India needs to monitor human influenza, poultry outbreaks and environmental exposure pathways together rather than treating them as separate surveillance problems.

The distinction is important: H1N1 circulating in humans is seasonal influenza, while H5N1 is primarily an avian influenza virus with zoonotic potential. ICMR has recently stated that the current H1N1 increase is consistent with seasonal influenza rather than a newly emerged H1N1 strain.

Kerala H5N1 outbreaks highlight the animal-health side

India reported 11 H5N1 outbreaks on poultry farms in Kerala, with the events detected from December 9 and confirmed by December 22. According to data reported to the World Organisation for Animal Health (WOAH), 54,100 birds died, predominantly ducks, while another 30,289 birds were culled as a precautionary measure.

That represents approximately 84,400 birds affected through mortality and precautionary culling.

The Kerala episode is particularly relevant because ducks and other domestic birds can provide an important interface between wild-bird influenza ecology and commercial or backyard poultry systems.

Human H5N1 surveillance: an important correction

The commonly cited statement that India has had “no confirmed human H5N1 cases in 2026” is no longer accurate.

The U.S. CDC’s June 26, 2026 global summary reported one human H5N1 infection in India during 2026, occurring in a child in March. Genetic analysis identified clade 2.3.2.1a, closely related to viruses previously reported in India and Bangladesh. Investigators noted two isolated poultry deaths in the child’s village, suggesting possible environmental exposure.

This makes accurate surveillance terminology particularly important: absence of a large human outbreak is not equivalent to absence of human infection.

India’s recent H5N1 human history

India recorded two fatal H5N1 infections in 2025, involving a child and an adult, according to the CDC. The country’s first officially reported human H5N1 infection occurred in Haryana in 2021, and the patient died in July that year.

Therefore, India’s recent history demonstrates a pattern of sporadic zoonotic spillover rather than sustained human-to-human transmission.

Why WHO’s One Health approach matters

WHO defines One Health as an integrated approach recognising the interdependence of human, animal, plant and ecosystem health. Avian influenza is specifically identified as one of the diseases for which integrated surveillance and control are important.

India already has institutional foundations for this approach. The National One Health Mission aims to develop integrated surveillance across the human-animal-environment interface, including genomic and metagenomic tools for detecting emerging pathogens.

WHO’s South-East Asia work also identifies avian influenza as a recurring example of pathogens emerging at the human-animal interface.

In July 2026, WHO reported that India had also transitioned to a new influenza surveillance interface within IDSP–IHIP, intended to improve dashboards, data visualisation and real-time surveillance and decision-making.

The surveillance architecture India needs

The strongest model would connect four data streams:

Poultry surveillance
↓
H5/H7 detection, mortality events, farm testing and genomic sequencing

Wild-bird & environmental surveillance
↓
Migratory birds, wetlands, poultry markets and environmental sampling

Human influenza surveillance
↓
ILI/SARI surveillance, exposure histories and influenza subtyping

Genomic surveillance
↓
Clade identification, reassortment monitoring and molecular epidemiology

Together, these systems can identify spillover earlier and distinguish seasonal human influenza from zoonotic avian influenza.

Key data

Analyst view: One Health should become operational, not simply conceptual

For India, the strategic lesson is straightforward. Human influenza surveillance cannot operate in isolation from animal-health surveillance.

Kerala’s poultry outbreaks demonstrate the scale at which H5N1 can affect livestock, while India’s sporadic human infections demonstrate that animal outbreaks can create opportunities for zoonotic exposure. At the same time, seasonal H1N1 activity can generate substantial human respiratory disease without being connected to H5N1.

The priority should therefore be integrated early-warning surveillance, linking veterinary laboratories, public-health laboratories, wildlife monitoring, genomic sequencing and field epidemiology.

That is the practical meaning of One Health: detect the virus where it first appears, understand how it moves between hosts and act before animal transmission becomes a human-health problem.