Malaria is a mosquito-borne infectious disease caused by a eukaryotic protest of the genus Plasmodium. It is widespread in tropical and subtropical regions, including parts of the Americas, Asia, and Africa. Each year, there are approximately 350–500 million cases of malaria, killing between one and three million people, the majority of whom are young children in Sub-Saharan Africa.
Ninety percent of malaria-related deaths occur in Sub-Saharan Africa. Malaria is commonly associated with poverty, but is also a cause of poverty and a major hindrance to economic development.
.Mosquitoes go through four stages in their life cycle: egg, larva, pupa, and adult or imago. Adult females lay their eggs in water, which can be a salt-marsh, a lake, a puddle, a natural reservoir on a plant, or an artificial water container such as a plastic bucket.
The first three stages are aquatic and last 5–14 days, depending on the species and the ambient temperature; eggs hatch to become larvae, then pupae. The adult mosquito emerges from the pupa as it floats at the water surface.
Adult females can live up to a month – more in captivity – but most probably do not live more than 1–2 weeks in nature.
Mosquito prefer some people over others. The preferential victim's sweat simply smells better than others because of the proportions of the carbon dioxide, octenol and other compounds that make up body odour.
The powerful semi chemical that triggers the mosquito's keen sense of smell is Nonanal.
Visible, irritating bites are due to an immune response from the binding of IgG and IgE antibodies to antigens in the mosquito's saliva. Some of the sensitizing antigens are common to all mosquito species, whereas others are specific to certain species.
There are both immediate hypersensitivity reactions (Types I & III) and delayed hypersensitivity reactions (Type IV) to mosquito bites (see Clements, 2000).
There are several commercially available anti-itch medications, including those taken orally, such as Benadryl, or topically applied antihistamines and, for more severe cases, corticosteroids such as hydrocortisone and triamcinolone.
Many effective home remedies exist, including calamine lotion and vinegar. A paste of meat tenderizer containing papain and water breaks down the proteins in the mosquito saliva. Both using a brush to scratch the area surrounding the bite and running hot water (around 49 °C) over it can alleviate itching for several hours by reducing histamine-induced skin blood flow.
On the other hand, excessive scratching can irritate the bite and break the skin, leading to prolonged recovery and the possibility of infection or scarring.