A district public health officer receives a report of a jaundice cluster affecting 45 individuals who consumed water from the municipal supply. Anti-HAV IgM is positive in 38 of the 45 cases. The MOST likely mode of transmission and the water source implicated is:

• A Blood-borne route; intravenous drug use among affected individuals
• B Faecal-oral route; contaminated municipal piped water supply ✓
• C Droplet route; contamination of overhead water tanks by infected birds
• D Sexual route; community-level high-risk behaviour

Explanation

Hepatitis A virus (HAV) spreads by the faecal-oral route and is the most common cause of acute jaundice outbreaks linked to contaminated water supplies in India. A cluster of jaundice cases linked to the municipal water supply with positive anti-HAV IgM strongly indicates a water-borne HAV outbreak — typically caused by sewage contamination of the water distribution system. HAV does not spread by blood-borne, droplet, or sexual routes as primary community transmission mechanisms.

Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.