Rising H3N2 Influenza Cases in Delhi-NCR: Causes, Concerns, and Way Forward

Context

Delhi and its neighbouring cities are witnessing a spike in H3N2 cases, a subtype of Influenza A virus, with doctors cautioning that the symptoms this time are more intense than in previous years. The surge has raised public health concerns, especially among vulnerable groups such as the elderly and those with comorbidities.

About H3N2 Virus

• Type: Subtype of Influenza A.

• Transmission:

  • Coughing and sneezing droplets.

  • Close contact with infected individuals.

  • Touching contaminated surfaces.

• Symptoms: Fever, cough, body ache, prolonged fatigue, sore throat, nasal congestion.

Current Trend (Delhi-NCR)

• Hospital Data (Holy Family Hospital, Delhi):

  • June–July: 5–6 positive cases.

  • August: ~80 cases.

  • September: ~100 cases.

  • Over 100 patients admitted in just 2 months.

• Pattern: Two seasonal spikes — Monsoon & Winter.

Vulnerable Groups

• Elderly population.

• Patients with diabetes, COPD, asthma, heart/kidney disease.

• Immunocompromised individuals (including transplant patients).

• Heavy smokers (longer recovery times).

Severity & Recovery

• Virus typically stays in the body for 5–7 days.

• Symptoms may persist for 2–3 weeks in vulnerable individuals.

• Some patients may develop secondary bacterial infections, worsening outcomes.

• Mortality rate remains low, though hospitalisations have increased.

Expert Opinions

• Dr. Sumit Ray (Holy Family Hospital): Warns of intense symptoms; surge in August–September.

• Dr. Chatterjee (Apollo Hospital): Notes rising OPD cases due to better awareness post-COVID.

• Dr. Jugal Kishore (VMMC, Safdarjung): Cautions that inadequate surveillance makes it hard to confirm trends; routine viral infections often go untested.

Preventive Measures

1. Vaccination: Annual influenza vaccines available; particularly recommended for:

   • Elderly

   • Patients with comorbidities

   • Healthcare workers

2. Hygiene: Regular handwashing, mask usage in crowded places.

3. Lifestyle: Adequate rest, balanced diet, avoiding smoking.

4. Medical Attention: Early consultation for high-risk individuals showing symptoms.

Broader Public Health Angle

• Surveillance Gap: Lack of robust influenza surveillance leads to underreporting.

• Post-COVID Awareness: More people are testing, hence higher reported cases.

• Seasonal Disease Burden: Flu spikes add pressure to urban healthcare systems.

UPSC Relevance

• GS Paper II (Governance & Social Justice): Public health challenges, vaccination, disease surveillance.

• GS Paper III (Science & Tech): Role of vaccines, epidemiology, and health infrastructure.

• Essay/Interview: “Seasonal viral outbreaks and the lessons for India’s healthcare preparedness.”

Practice Questions

Mains:

1. Discuss the role of influenza surveillance in managing seasonal outbreaks such as H3N2.

2. Post-COVID, how can India strengthen its healthcare system to tackle recurring viral outbreaks?

Prelims Pointers:

• H3N2 = Subtype of Influenza A virus.

• Two annual peaks: Monsoon & Winter.

• Transmission: Droplets, contact, contaminated surfaces.