Which statement about Dengue is true?

• A. Transmitted by ticks only
• B. A vaccine exists
• C. Local transmission by Aedes albopictus detected in Hawaii (2001-2002)
• D. It is not present in the Americas

Answer: (C)

Dengue is transmitted by Aedes mosquitoes, not ticks, and it can spread locally when a competent vector is present. The Hawaii outbreak in 2001–2002 is a documented example where local transmission occurred due to Aedes albopictus, showing that dengue can establish transmission in areas outside the tropical core if the mosquito vector is around. This makes the statement about local transmission by Aedes albopictus in Hawaii during that period true.

The other ideas don’t fit: dengue is not tick-borne, so “ticks only” is incorrect; while a vaccine exists in some contexts, it doesn’t change the basic transmission history shown by that Hawaii outbreak; and dengue has long been present in the Americas, so saying it isn’t there is false.