During pre-monsoon Aedes survey in a town, the House Index is found to be 12 and Breteau Index is 15. According to WHO criteria, this level of infestation indicates:
- A Low risk, no action needed
- B High risk, outbreak imminent, intensive vector control needed ✓
- C Moderate risk, routine surveillance only
- D Index values are irrelevant for dengue risk assessment
Correct answer: B. High risk, outbreak imminent, intensive vector control needed
Explanation
WHO interprets larval indices as follows: House Index below 5 percent is acceptable, 5 to 9 percent signals intermediate risk needing intensified action, and an index of 10 percent or above denotes high risk of an impending outbreak requiring emergency vector control. With HI of 12 percent and BI of 15, the town falls squarely in the high-risk band, so option C understates the response required.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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