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हिन्दी — Read in HindiCommunicable 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 5 of 8 articles, those that changed from 1 July to 30 September 2026.Show all
Outbreaks in people
Chandipura virus
Copy link to Chandipura virusPrelims and Mains
Chandipura virus is a rhabdovirus related to rabies, carried mainly by sandflies.
- It causes fever that can turn into acute encephalitis, inflammation of the brain, in children, killing within days.
- Outbreaks recur in summer in Gujarat, Maharashtra and Rajasthan.
- Testing animals beside people in an outbreak is One Health in practice.
What changed
26 Jul 2026BriefRajasthan stepped up surveillance after two girls from Dungarpur and Sirohi who died tested positive. The Hindu, 26 Jul 2026: Rajasthan on alert after deaths linked to Chandipura virus (opens in a new tab)
Leptospirosis
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Leptospirosis is a bacterial zoonosis caused by Leptospira from the urine of rodents and other animals.
- The bacteria survive in standing water and soil and enter through cuts or mucous membranes, so the disease peaks after monsoon floods among farmers, cleaners and construction workers.
- It does not pass from person to person.
- Treated early with antibiotics it is mild; diagnosed late it goes on to pulmonary haemorrhage and multi organ failure, which is what kills.
What changed
3 Aug 2026BriefIt killed 50 people in Kerala in July 2026, the State's deadliest communicable disease that month, and late diagnosis was named as the cause. The Hindu, 3 Aug 2026: Why is Kerala facing high leptospirosis mortality? | Explained (opens in a new tab)
Surveillance and preparedness
Disease surveillance and biological disaster preparedness
Copy link to Disease surveillance and biological disaster preparednessPrelims 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.
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
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
Animals and One Health
Zoonoses action plan
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The National Action Plan for Prevention and Control of Zoonoses is built on the One Health approach and names ten priority zoonoses.
- The ten run from anthrax and brucellosis to Nipah, rabies and Zika.
- Each State is to write its own plan on the same lines.
What changed
6 Jul 2026New
- A draft National Action Plan for Prevention and Control of Zoonoses, built on the One Health approach, has been prepared, and States will write their own plans on the same lines.
- The ten priority zoonoses are anthrax, brucellosis, Kyasanur Forest Disease, Crimean-Congo haemorrhagic fever, Nipah, mpox, rabies, leptospirosis, scrub typhus and Zika.
Programmes and treaties
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.