To prevent the spread of yellow fever across borders, the area surrounding airpos and seapos should be free from breeding of aedes mosquito. What is the area to be kept free of aedes mosquito/insect vector?
**Core Concept**
The yellow fever virus is transmitted primarily through the bite of infected female Aedes mosquitoes, specifically Aedes aegypti. To prevent the spread of yellow fever, it is essential to eliminate or reduce the breeding sites of these mosquitoes.
**Why the Correct Answer is Right**
The World Health Organization (WHO) recommends a 400-meter radius area around airports and seaports, known as the "airport perimeter" or "port zone," to be free from breeding sites of Aedes mosquitoes. This area is crucial in preventing the introduction and spread of yellow fever and other mosquito-borne diseases. The 400-meter radius is chosen based on the flight range of Aedes mosquitoes, which can travel up to 400 meters in search of a host.
**Why Each Wrong Option is Incorrect**
* **Option A:** The 100-meter radius is too small to effectively prevent the spread of yellow fever, as Aedes mosquitoes can travel farther than this distance.
* **Option B:** The 1-kilometer radius is excessive and impractical for airport and seaport areas, where land is often limited and development is critical.
* **Option C:** The 200-meter radius is not a standard recommendation by the WHO or other public health organizations for preventing yellow fever transmission.
**Clinical Pearl / High-Yield Fact**
It is essential to note that the 400-meter radius area should be free from standing water, which serves as a breeding site for Aedes mosquitoes. This includes eliminating containers, such as buckets, tires, and flowerpots, that can collect and hold water.
**Correct Answer: D. 400-meter radius area.**