In an at-risk area, staying in air-conditioned or well-screened room, or sleeping under an insecticide-treated bed net is recommended. Bed nets should be tucked under mattresses, and can be sprayed with a repellent if not already treated with an insecticide. Monitoring and control
West Nile virus can be sampled from the environment by the pooling of trapped mosquitoes via ovitraps, carbon dioxide-baited light traps, and gravid traps, testing blood samples drawn from wild birds, dogs, and sentinel monkeys, and testing brains of dead birds found by various animal control agencies and the public.Testing of the mosquito samples requires the use of reverse-transcriptase PCR (RT-PCR) to directly amplify and show the presence of virus in the submitted samples. When using the blood sera of wild birds and sentinel chickens, samples must be tested for the presence of WNV antibodies by use of immunohistochemistry (IHC) or enzyme-linked immunosorbent assay (ELISA).Dead birds, after necropsy, or their oral swab samples collected on specific RNA-preserving filter paper card, can have their virus presence tested by either RT-PCR or IHC, where virus shows up as brown-stained tissue because of a substrate-enzyme reaction. West Nile control is achieved through mosquito control, by elimination of mosquito breeding sites such as abandoned pools, applying larvacide to active breeding areas, and targeting the adult population via lethal ovitraps and aerial spraying of pesticides.
Some ultralight hot air balloons are hopper balloons, while others are regular hot air balloons that carry passengers in a basket. Electric
Advancements in batteries, motors, and motor controllers has led to some practical production electric propulsion systems for some ultralight applications. In many ways, ultralights are a good application for electric power as some models are capable of flying with low power, which allows longer duration flights on battery power.In 2007, the first pioneering company in this field, the Electric Aircraft Corporation, began offering engine kits to convert ultralight weight shift trikes to electric power. The 18 hp motor weighs 26 lb (12 kg) and an efficiency of 90% is claimed by designer Randall Fishman. The battery consists of a lithium-polymer battery pack of 5.6kWh which provides 1.5 hours of flying in the trike application. The company claimed a flight recharge cost of 60 cents in 2007.A significant obstacle to the adoption of electric propulsion for ultralights in the U.S. is the weight of the battery, which is considered part of the empty weight of the aircraft despite efforts to have it considered as fuel. As battery energy density improves lighter batteries can be used. See also
Aerosport (airshow)
Backpack helicopter
Jetpack
Nanolight
Experimental Aircraft Association
Recreational Aviation Australia
United States Ultralight Association
United States Powered Paragliding Association
Volksflugzeug

References
External links
 Media related to Ultralight aircraft at Wikimedia Commons