Summer is on its way, and that means its time for BBQ's, family and friends. Flies can be an unwanted guest, spreading their germs everywhere!
Typically, adult flies are very small to medium sized and have only two wings. In place of hind wings, flies carry a pair of club-shaped balancers called halteres. Flies usually have compound eyes and a pair of often short antennae. Adult mouth parts are of the sucking or piercing and sucking type. Larvae are legless and mostly maggot like in appearance, often tapering towards the head end of the body.
All flies undergo a complete metamorphosis during their development. Eggs or sometimes live young, are laid in the medium that will serve to feed the larvae. The feeding activity of the house fly and blowfly larvae often raises the immediate temperature, facilitating faster development of the fly.
The development of the fly is such that larvae are largely restricted to their feeding medium. (eg trash) Winged adults, on the other hand, are mobile. When a give population of adults develop from a particular larval-feeding area, the extent to which they travel and their direction of travel will be determined by a number of factors, among which is an attraction to areas that offer food, moisture and egg laying sites.
The list of disease causing organisms that flies may harbour on or in their bodies is enormous. Diseases that can be spread by flies include Salmonella food poisoning, dysentery, typhoid fever, cholera, hepatitis, tuberculosis, poliomyelitis, various parasitic worms and many others. Some adult flies pierce the skin of humans or other animals in order to suck blood. Because they are apt to inject saliva, mild to severe irritation may ensue. As well, this feeding habit may serve to distribute diseases (eg malaria, dengue fever) by cyclical or biological disease transmission.