In an urban dengue control programme, larval surveys report House Index values monthly. According to WHO guidance, epidemic dengue transmission is considered unlikely when the House Index is maintained below:
- A 20%
- B 10%
- C 5% ✓
- D 1%
Correct answer: C. 5%
Explanation
The House Index is the percentage of houses inspected that harbour Aedes larvae or pupae. WHO considers transmission unlikely when it stays below 5 percent, a benchmark originally derived for yellow fever and applied to dengue programmes. Values between 5 and 10 percent indicate a receptive situation warranting intensified action, and above 10 percent signals imminent outbreak risk. Container Index and Breteau Index are complementary but the 5 percent threshold is quoted for House Index.
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.