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Communicable diseases, animal health and One Health

Infectious diseases in people and animals: outbreaks, surveillance, India's disease programmes, and the One Health approach that joins human, animal and environmental health. Prelims has asked which disease the H1N1 virus is linked to and whether viruses spread only through vectors.

Foundation note: The diseases Prelims asks: pathogen, vector, programme

Showing 1 of 8 articles, those that changed from 1 to 30 September 2026.Show all

Surveillance and preparedness

Disease surveillance and biological disaster preparedness

Prelims and Mains

Disease surveillance is how India watches for outbreaks, through three networks; biological disaster preparedness is how it responds to an epidemic, a pandemic or a deliberate release.

Influenza A subtypes are named for two surface proteins, haemagglutinin (H) and neuraminidase (N); H1N1 caused the 2009 pandemic and settled into the seasonal mix.

Influenza surveillance

Testing
- Influenza like illness and severe acute respiratory infection (SARI) samples tested year round
- No alert thresholds
Coordination
- Split between ICMR, NCDC and the States
Treatment
- Under 10 per cent of admitted patients get antivirals

From The Indian Express, 3 September 2026, and Frontline, 8 September 2026

Watching

The Integrated Disease Surveillance Programme collects weekly reports from every district.
The Indian Council of Medical Research's Viral Research and Diagnostic Laboratory network has four regional sequencing hubs and wastewater surveillance.
Sentinel sites watch named diseases, such as dengue.
Surges are compared by incidence, new cases per population over a period, not by raw counts.
What the system lacks is a trigger: it watches continuously without a rule for declaring that an outbreak has begun.
The bodies that watch are not the bodies that act.

Responding

A biological disaster, an epidemic, a pandemic or a deliberate release, is handled under the Disaster Management Act, 2005 as well as health law.
The Health Ministry is the nodal ministry, and the NDMA's 2008 guidelines and the 2019 National Disaster Management Plan set out who does what.
ICMR's virology laboratories and two mobile BSL 3 laboratories do the testing.
NDRF teams are trained for chemical, biological, radiological and nuclear response.

What changed

3 Sep 2026
- Seasonal influenza surged across India with H1N1 reported from several cities; the season's vaccine matched the circulating strain but uptake was low.
- A column called the surge a test for the next pandemic and proposed an integrated command structure to replace the split between surveillance and response.
The Indian Express, 3 Sep 2026: India's current flu spike is a test for the next pandemic. Failure is not an option (opens in a new tab) · Frontline, 8 Sep 2026: Public health is political: Brian Wahl (opens in a new tab)

UPSC has asked

Prelims 2015: the disease the H1N1 virus is linked to
Prelims 2013: whether viruses spread only through biological vectors

Also filed elsewhere

Dengue vaccines: Qdenga, DengiAll and antibody dependent enhancement · on Vaccines and immunisation
Dengue has four serotypes, and antibodies from a first infection can help a different serotype enter cells in a second, which is antibody dependent enhancement and is why dengue vaccines are hard to design: vaccination raises type specific antibodies, which block one serotype, and cross reactive antibodies, which block all four only at high levels and can enhance a new infection into severe dengue once they wane.